ML19319B827

Lynchburg Research Ctr Tests.

ML19319B827
Person / Time
Site:	Davis Besse
Issue date:	12/16/1976
From:	BABCOCK & WILCOX CO.
To:
References
NUDOCS 8001280658
Download: ML19319B827 (48)

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TABLE OF CONTENTS

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Page 1.0 INTRODUCT ION - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 1-1 1.1 Background ---------------------------------------------- 1-1 1.2 Instrument Series ----------------------------- ----- ---

1-1 1.2.1 Source Range Ch anne l - - - - - - - - - -- - - - - - - - -- - - - - - - - - 1-1 1.2.2 Intermediate Range Channel ----------------------- 1-1 1.2.3 Powe r Range Channe l - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 1-1 2.0 TEST PROGRN4 ------------------------------------------------- 2-1

. 2.1 Ge ne ral - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 2-1 2.2 Power Range Tests --------------------------------------- 2-1 2.2.1 Detector Powe r Supply -- - - - - -- -- - - - - - - - - - - - - - - -- - - 2-1 '

2.2.2 Line ar Amp lifier - - - - - - - - - - - - -- -- - - -- - - - - - - - - - - - - - - 2-1 2.2.3 B is tab le Te s ts - - - - - - - - + - - - - - - - - - - - - - - - - - - - - - - - - - - 2-1 2.2.4 Graphite Pile Test -------- ---------------------- 2-2 2.2.5 LPR Test ---------- ------------------------------ 2-2 2.3 Intermediate Range Tests -------------------------------- 2-2

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2.3.1 De te cto r Powe r S upply - - - - - - - - - - - - - - - - - - - - - - - - - - - - 2-2

-2.3.2 Log N Amp lifie r - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 2-2 2.3.3 Bistable Tests ---------------------------- ------

2-2 2.3.4 Rate-of-Change Amplifier ----------- --- - ------ ----- 2-3 2.3.5 Auxiliary Power S upply - - - - - - - - - - - - - - - - - - - - - - - - - - - 2-3 2.3.6 LPR Te s t - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 3 2.4 S ource Range Te s ts - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 2-3 2.4.1 Detector Powe r Supply - - -- --- - -- -- -- -- -- -- -- - - ---- 2-3 2.4.2 B is tab le Tes ts - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 2-3 2.4.3 Count Rate Amplifier and Preamplifier Tests ------- 2-4 2.4.4 Rate - o f- Change Ampli fie r - - -- - - -- - - - -- -- -- - - - - -- - 2-4

, 2.4.5 Graphite Pile Test --------- - - - - - - - - - - - - - - - , - - - - - -

2-4 2.4.6 LPR Test -----------------------------------------

2-4 2.5 Test Circuits --------------------------- - ------------- 2-5 Scurce Range Test Circuit 2.5.1 ------------------------

2-5 2.5.2 Intermediate Range Test Circuit --- - - -- -- ------ --- 2-5 2.5.3 Power Range Tes t Ci rcuit - - - - - - - - - -- - - - - - - -- - - -- - - - 2-5 3.0 POWER RANGE TEST RESULTS - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 3-1 3.1 De te cto r Powe r S upply - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 3-1 3.2 L ine ar Amplifie r - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 3-1 3.3 B is t ab l e Te s ts - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 3-3

. 3.4 ~Lynchburg Pool Reactor Test ----------- ------------------

3-4 3.5 Comments ------------------------------------- ----------

3-4

, , 4.0 IhTERMEDIATE RANGE TEST RESULTS - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 4-1 4

4.1 De te cto r Powe r Supp ly - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 4-1 1

t 1.0 INIRODUCTION

1.1 BACKGROUND

The objective of the NDC program was to give design assistance for the

. . Bailey Meter Company's nuclear instrumentation line, and to conduct extensive test and analysis on the prototype equipment already designed.

1.2 INSIBIENT SERIES Three flux channels a:d the system power supply were tested.

1.2.1 Source Range Channel Included in the source range channel were:

1. Preamplifier.

2. Detector power supply

- 3. Test circuit

, 4 Count rate amplifier

5. Rate-of-ch nge amplifier

6. Bistable 1.2.2 Intermediate Range Charmel Included in the intermediate range channel were: ,

1. Detector power supply

2. Auxiliary power supply

3. Test circuit

- 4. Log N amplifier .

. 5. Rate-of-change amplifier

6. Bistable 1.2.3 Power Range Charmel Included in the power range channel were:

1. Detector power supply

2. Linear amplifier

3. Bistable 4

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f 2.0 TEST PROGRA\1 2.1 GENERAL The test program was written to test (1) the individual modules under laboratory conditions,. (2) the individual channels as a system with a neutron source where applicable, and (3) the individual channels as a system using the Lynchburg Pool Reactor (LPR) as a neutron source.

The test program was intended,with the use of a neutron source, to ascer-tain whether the prototype equipment would meet the specifications set forth by the Bailey Meter Canpany (BMC).

2.2 , POWER RANGE TESTS 2.2.1 Detector Power Supply The detector power supply was tested as follows:

1. Temperature variation effects

2. Linearity over the operating range

3. Ripple magnitudes of d-c output 4 Overload limit reset of d-c output 2.2.2 Linear Amplifier ,

2 e linear amplifier of the power range was tested as follows:

1. Voltage variation of 115 V a-c power supply

2. Accuracy and linearity of the amplifier over the operating range

3. Response of the linear amplifier to variations in magnitudes of step inputs 4 Foldover of the amplifier due to overload of the input signal

5. Signal-to noise ratio of the amplifier

6. Noise interference effects

7. Temperature variation effects

8. Cable length variation effects 2.2.3 Bistable Tests The bistable was tested as follows:

1. Temperature variation

2. Internal d c supply variation

3. Trip and retrip set point accuracy and resolution

4. Response time to an input step 2-1

2.2.4 Graphite Pile Test i The graphite pile neutron sources were insufficient for this range of current. .

2.2.5 LPR Test The LPR test was as follows:

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1. Gain adjustment and resolution of the channel

, 2. Cable length variation l, 3. LPR power variation and input signal overload l 4. Detector power supply loading

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5. Noise rejection of the channel j 2.3 INTER 5EDIATE RANGE TESTS , 2.3.1 Detector Power Supply The detector power supply was tested as follows:

1- 1. Temperature variation effects i

. 2. Linearity over the operating range

. 3. Ripple magnitudes of d-c output

4. Overload limit reset of d-c output 2.3.2 Log N Amplifier .

The log N amplifier was tested as follows:

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1. Accuracy and linearity of the amplifier over the designed operating range

2. Response of the amplifier to various magnitudes of step input

3. Foldover of the amplifier due to overload of the input signal

. 4 Signal to-noise ratio of the amplifier

5. Noise interference effects

,_ 6. Cable length variation effects

7. Temperature variation effects 2.3.3 Bistable Tests The bistable was tested as follows:

1. Temperature variation effects

2. Internal d-c supply variation

3. Trip and retrip set point accuracy and resolution

4. Response time to an input step signal s..

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2-2

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TABLE OF CONTENTS (cont'd) -

Page 4.2 Lo g N Ampli fie r - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 4-1 4.3 B i s t ab le Te s t s - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 4-4 4.4 Rate -o f-Change Amplifie r - - - - - - - -- - - - - - - -- -- -- - ----- - - -- - 4-4 4.5 Auxilia ry Powe r Supply - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 4-5 4.6 Graphite Pile Test -------------------------------------- 4-5 4.7 Lynchburg Pool Reactor Test ---------- -------------------- 4-5 4.8 Commen t s - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 4-6 5.0 SOURCE RANGE TEST RESULTS ----------------------------------- 5-1

. 5.1 De tecto r Powe r Supply - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 5-1 -

5.2 Count Rate Amplifier and Preamplifier Tests ------------- 5-1 5.3 Bistable Tests ------------------------------------------ 5-8 5.4 Rate -of-Change Amplifier -- - -- -- ------ -- ------ ----------- 5-9 5.5 Graphite Pile Test -------------------------------------- 5-9 5.6 Lynchburg Pool Reactor Test ----------------------------- 5 5.7 Problems ----------------------------------------------- 5-12 5.8 Comments ------------------------------------------------ 5-12 -

6.0 SOURCE AND INTElbEDLATE RANGE TEST CIRCUITS ------------------ 6-1 7.0 ADD IT IONAL CGMENTS - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 7-1 LIST OF TABLES Table 3.1 Detector Power Supply Measurements ---------------------------- 3-2 3.2 Linear Amplifier Measurements --- ---------------------------- 3-2

- 4.1 Detector Power Supply Linearity Test ------------------------- 4-2 4.2 Log _N Amplifier Test --------- ------------------------------- 4-2 4.3 Rate-of-Change Amplifier ------------------------------------- 4-7 4.4 Linearity of Auxiliary Power Supply -------------------------- 4-7 5.1 - Accuracy of Detector Power Supply ---------------------------- 5-2 5.2 Accu racy o f Ampli fication - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -- - - - - -- 5-2 5.3 Test of Rate-of-Change Amplifier ----------------------------- 5-10 ii

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TABLE OF CONTENTS (Cont'd)

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List of Figures Figure Page

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3.1 Frequency Response of Power Range Amplifier ------------------ 3-6 4.1 Frequency Response For Rate-of-Change Amplifier -------------- 4-8

. . 4.2 LPR Te s t Re sults - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 4-9

, Photo A ------------------------------------------------------ 4-9 Photo B ------------------------------------------------------ 4-9 4.3 Photo D ----------------------------------------'------------' 4-10 Photo E ------------------------------------------------------ 4-10 5.1 Variation of Cable Length ------------------------------------ 5-10 Photo A ------------------------------------------------------ 5-10 Photo B ------------------------------------------------------ 5 10

. Photo C ------------------------------------------------------ 5-11 Photo D ------------------------------------------------------ 5-11 Photo E ------------------------------------------------------ 5-12 Photo F ------------------------------------------------------ 5-12 Photo G ------------------------------------------------------ 5-13

, Photo H ------------------------------------------------------ 5-13 5.2 Frequency Response (Closed Loop) For SR Rate-of-Cliange -

Amplifier ---------------------------------------------------- 5-14 5.3 Random Input (pps) vs. d-c Voltage Output of the Count Rate

, Arplifier ---------------------------------------------------- 5-15 5.4 Unifom Input (pps) vs. d-c Voltage Out Amplifier ---------------------------- put of the Count Rate -----------------------

5-16 5.5 Count Loss Curve Tor Source Range Channel -------------------- 5-17 7.1 Interconnection of System ------------------------------------ 7-2 e

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2.3.4 Rate-of Change Amplifier

. The rate of-change amplifier was tested as follows:

1. Accuracy, linearity, and repeatability 2, Response time to various input step magnitudes

3. Temperature variation effects

4. Foldover of the amplifier due to overload of the input signal

5. Ripple or noise of d-c output voltage

6. Noise rejection capabilities 2.3.5 Auxiliary Power Supply The auxiliary power supply was tested as follows:

1. Linearity over the operating range .

2. Temperature variation effects 3, Ripple magnitudes of d-c output 4, Overicad limit reset of d c output 2.3.6 LPR Test j The LPR test was as follows: .

1. Foldover cf the amplifier due to input signal overicad

2. Response of the channel to power variation -

3. Noise rejection of-the channel 4 Cable length variation effects 2.4 SOURCE RA.NGE TESTS 2.4.1 Detector Power Supply The detector power supply was tested as follows:

1. Temperatures variation effects

2. Linearity over the oper? ting range

3. Ripple magnitudes of the d-c output J. Overload limit reset of the d-c output 2.4.2 Bistable Tests The bistable amplifier was tested as follows:

1. Temperature variation effects

2. Internal d c supply variation l 3. Trip and retrip set point accuracy and resolutien j 4 Response time to an input step signal l

2-3

f 2.4.3 Count Rate Amplifier and Preamplifier Tests The count rate amplifier and prea=plifier were tested as an integral unit as follows:

. 1. Sensitivity of preamplifier

2. Pulse pair resolution

3. Accuracy and linearity over operating range

4. Response over operating range and at various magnitudes of step input

5. Rise time and clipping (fall time)

6. Signal-noise ratio

7. Cable length variation

8. Interference noise rejection

9. Temperature variation effects

. 2.4.4 Rate-of-Change Amplifier

. The rate-of-change amplifier was tested as follows:

1. Linearity and repeatability

2. Response time for various input step magnitudes

3. Temperature variation effects

4. Foldover of the amplifier due to overload of input signal 2.4.5 Graphite Pile Test The graphite pile neutron source test was as follows:

1. Compatibility of the neutron detector to preamplifier

. 2. Response time

. 3. Noise interference effects

4. Cable length variation effects 2.4.6 LPR Test The LPR test was as follows:

1. Random - uniform count ccmparison

2. Input signal overload effect

3. Count loss of system 4 Cable length. variation

5. Noise interference effects 2-4

2.5 TEST CIRCUITS No test program was set up to test the BS1C's test circuit of each channel.

H:: wever, each unit was tested for functional use cnly.

I 2.5.1 Source Range Test Circuit The test circuit was tested as follows:

i

1. Operate

2. Test operate

3. Count rate amplifier at 100 Ez input 4 Count rate amplifier at 4 Ez input

5. Count rate amplifier at 1 Hz input

6. Count rate anp11fier, trip calibrated

7. Rate of change, zero *

8. Rate of change, range 9, Rate of change, trip calibrated 2.5.2 Intermediate Range Test Circuit The test circuit was tested as follows:

1. Operate

2. Test operate ,

-3 Log N amplifier,10

3. ampere input 4, Log N' amplifier, balance

5. Log N amplifier, calibrated

6. Log N amplifier,10 ~I1 ampere input 7 Log N at:plifier, trip calibrated

8. Rate of change, 0 dec/ min

9. Rate of change,10 dec/ min

10. Rate of change, trip calibrated 2.5.3 Power Range Test Circuit The power range test circuit was not available for function tests.

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3.0 POWER RANGE TEST RESULTS 3.1 DETECTOR POWER SUPPLY The power range detector supply was received, inspected, and calibrated according to BBC's instructions.

. He detector power supply was tested for a temperature variation of 20 C

, from a nominal temperature of 25 C. The total voltage variation at 1200 d-c volts for SC and 45 C extremes was 2.0 volts.

The detector power supply was tested for linearity at 25 C over the design range of 600 to 1200 d-c volts. Table 3.1 gives the recorded data. The -data shows a test jack accuracy of 0.12% and a meter accuracy of 1.2%. The calculated data shows s maximum deviation of 0.05% in linearity over the operating range.

The detector power supply was tested for a-c ripple on the d-c output voltage. The ripple was a 4.0 mV peak-to-peak 7150 Hz signal riding the output of 1200 d-c volts.

The detector power supply was tested for an output short circuit. hhen the output was short circuited, the voltage dropped to zero. hhen the short circuit was removed, the voltage returned to its set value. This functionally

. tested the limit reset.

3.2 LINEAR AMPLIFIER The power range amplifier was received,' inspected, and calibrated according to BMC's instructions.

The power range amplifier was tested for the effects of variation of the

. 115 a-c volt line to the system power supply. There was no noticeable variation

. In the monitored amplifier output voltage as the 115 a-c vol't line voltage was varied.

The power range amolifier wa.* tested for linearity at 25 C over the operating range of 0 to 10 d-c valts (0-125%) for the three coarse gain positions. Table 3.2 gives the recorded data. The data shows a maximum deviation of 0.34% in linearity for the gain position 1 operating range. The entire data shows an accuracy of 0.89%. This large value is probably caused by the 1% tolerance of the selected input resistor.

The power range amplifier was tested for response time to an input step signal. The 99% response time was no more than 1.0 ms for a 100% range of input step signal and was 0.2 ms for a 10% step. He three ranges gave results within 0.2 ms of each other.

3-1 L J

TABLE 3.1 DETECTOR POWER SUPPLY >EASURBENTS i

Test Jack Accuracy;

[V,-Ftj 200)]

Sieter Reading, measured, test jack, volts volts volts x 100/V*

595 600.1 5.995 0.08 700 701.5 7.008 0.09 810 800.5 7.995 0.12 910 901.2 9.005 0.07 1010 1000.1 9.992 0.09 1110 1100.7 11.002 0.04 -

1200 1199.7 11.986 0.09 TABLE 3.2 LINEAR AitPLIFIER SEASUREETS Gain Input Resistor (R ),

s Input V ltage (Vin),

Output .

V ltage (Vout)' V

'f feter Position ohms volts volts in Indication, %

1 10,000 0.995 0.995 0 00 12.4 1 10,000 5.005 4.988 0.34 61.5 1 10,000 9.004 8.974 0.33 111 1 10,000 10.002 9.971 0.31 122.5 2 100,000 1.002 1.005 0.29 12.5 2 100,000 5.005 5.021 0.32 62.5 2 100,000 8.992 9.029 0.41 111 l 2 100,000 10.003 10.037 0.34 123 3 1,000,000 1.002 0.995 0.69 12.4 3 1.000,000 5.007 4.965 0.84 62 3' 1,000,000 9.004 8.923 0.89 110 3 1,000,000 10.003 9.915 0.88 122.5 I

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The power range amplifier was tested for foldover due to input signal

( overload. The input signal was increased to 300% of the range setting (gain  !

position). No foldover was noted for this value at any temperature. The l 1

recovery time due to this input signal overload was less than 1.0 ms. l The power range amplifier was tested for signal-to-noise ratio as defined by the equation below:

ratio of signal to noise = out (with Ein= 1.0 v, R "UI) s Eo t (with Ein = 0.0 v, R "DI) s where E out is the peak-to-peak value plus any d-c voltage.

The signal-to-noise ratio was 99.5. The circuit noise as measured on a Ims -

voltmeter was 58db or a peak-to-peak measured value of 10 mV.

The power range amplifier was tested for the effects of interference noise.

The noise generated was from a soldering gun on-off switch, 60 hert: induction, 60 hert: directly fed into the amplifier, and the switching of the compressor on the air conditioning temperature chamber. The noise spikes observed at the amplifier output when the motor was switched and when the soldering gun was switched were not measured in absolute value. The dire'ctly fed 60-hertz source -

was observed ~ at the amplifier output to have little or no attenuation. It should be pointed out that this test was conducted with a low impedence source and not the high impedence normally found with a detector.

The power range amplifier 'was tested for a temperature variation of 20 C above and below 25 C. The temperature variation had little or no effect on the accuracy, linearity, response time, and signal-to-noise ratio.

, The power range amplifier was tested for cable length variation effects.

The length of the cable was varied between 5 and 370 feet with no effect noted in signal-to-noise ratio, response time, or noise interference. The attenuation was less than 1 mV.

3.3 BISTABLE TESTS The power range bistable amplifier was received, inspected, and calibrated (according to BMC's instructions).

The bistable amplifier was tested for trip accuracy and retrip accuracy.

The trip accuracy was 0.24%, and the retrip accuracy was 0.04%. The retrip may also be defined as the resolution.

l 3-3 l

4 He bistable amplifier was tested for internal reference voltage supply variation, which was 0.04%.

The voltage variation was 0.04% over a temperature variation of 20 C.

Se bistable amplifier was tested for response time. The response time

. for a 3.0-volt step was 36 ms.

The bistable amplifier was tested for the effects of a 120 C variation from the normal temperature of 25 C. The temperature variation caused a 0.19% change in accuracy.

3.4 LYNWBURG POOL REACIOR TEST The power range channel was tested as a~ system on the LPR.

He first test was for gain adjustment. The power was increased in decade ,

steps (using the standard LPR instruments), and the power range amplifiers d-c voltage output was recorded for each coarse gain setting. h' hen the power was held at the desired magnitudes as closely as possible, the accuracy of the amplifier was 0.21% between gain settings. All three coarse gain ranges were used to cover the operating range with different magnitudes of reactor power.

The fine gain was also adjusted for its resolution.

Re power range channel was tested for cable length variation while the .

reactor was operating. He input length of the cable had little or no effect on the amplifier's output magnitude.

He power range channel was tested for an input signal overload along with power variation. He system responded well with power variation. No foldover was noted for an input signal overload.

Le power range channel was tested for detector power supp1, ioading when the input current signal was large. The detector power supply was set at 750 d-c volts and was monitored as the signal was increased to 2.0 ma. No devia-tion from the set value of 750 d . volts was noted.

The power range channel was tested for noise rejection. The noise for the three coarse gain settings was recorded as 150 mV (low gain),120 mV (medium gain), and 30 mV (high gain).

3.5 00bMENTS Coments about the power range channel are as follcws:

1. Photographs were taken of the noise problem associated with the amplifier output. Further investigation of the system by CEL perscnnel to discover the source of noise led to testing the power range amplifier for a frequency response. This test inaicated instabilities due to feedback elements (see Figure 3.1) .

3-4

A single time constant between 1.0 and 10 ms was suggested for all three coarse gain settings.

2. Testing personnel thought that the fine gain adjustment was too coa:sa

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and that that gain adjustments needed refinement.

. 3. Many minor problems associated with prototype equipment such as solder

, joints, wiring, and diagrams were corrected with little difficulty.

4. BMC was made aware of the problems and our cc m ents by phone liaison, by monthly progress reports, and by quarterly reports. These problems were subsequently corrected.

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4.0 INTERhEDIATE RANGE TEST RESULTS 4.1 DETECTOR POWER SUPPLY The detector power supply was received, inspected, and calibrated according 3

to SIC's instructions.

The detector power supply was tested for a temperature variation of 20 C from a ncminal temperature of 25 C. The total voltage variation at 1~00 d-c volts for 5 C and 4 ' extremes was 1.0 volt.-

The detector power supply was tested for linearity at 25 C over the design range of 600 to 1200 d-c volts. Table 4.1 gives the recorded data. This data shows a test jack accuracy of 0.17%. The calculated data shows a maximum deviation in linearity of 0.17% over the operating range. -

The detector power supply was tested for a-c ripple on the d-c output voltage. The ripple was a 5.0 mV peak-to-peak 7150 H: signal riding the 1200-volt d-c output.

The detector power supply was tested for an output short circuit. hhen the output was short-circuited, the voltage dropped to zero, hhen the short circuit was removed, the voltage returned to its set value. This functionally

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tested the limit reset.

4.2 LOG N AMPLIFIER The log N amplifier

• was received, inspected, and calibrated according to BIC's instructions.

The log N amplifier was tested for accuracy and linearity. Table 4'.2 gives the recorded data. This data shows an accuracy of 3.76% over the range of 10 -10 to 10 ~3 ampere. The calculated data shows a linearity of 3.0% over the range of 10 -10 to 10 -3 ampere.

The log N amplifier was tested for response time to various input step magnitudes. The response time depended cn the feedback network resistor. The

-10 10 ampere input step had a response time of approximately 25 seconds; the l 10 ampere input step had a response time of 3.0 seconds; the 10 -5 ampere input had a response time of 1.8 seconds; and the 10 ampere input had a response time of 0.8 second. The log N amplifier was tested for foldover due to input l signal overload. The input signal was increased to a current of 10 mA, and j algnored in these tests was a 1.6 mV oscillation an the amplifier's d-c output.

This same oscillation appeared at test jack No. 2 as 11,0 mV.

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no foldover was noted. The input signal was connected to a 10-volt peak-to-peak

, 60 Ht signal. No harm was noted in the amplifier, and the a-c output ripple was 32 mV.

~

The log N amplifier was tested for signal-to-noise ratio. The ratio of

. . "d-c signal plus noise" to noise at 10 -11 ampere was approximately 60.

The log N amplifier was tested for noise interference. hhen 60 H: were induced in parallel into the input cable, a 4.0 mV noise resulted on the output.

The 60 H: (10 volts peak to peak) direct feed from a low-impedence source resulted in a 36 mV output.

The switching on and off of a soldering gun near the input cable produced noise spikes on the d-c output of the amplifier at all input current magnitudes.

It was again noted that a ringing effect occurred at 10 -8 and 10 -7 ampere, but -

not at 10 ~9 and 10 -5 ampere of input current.

. NOTE: This noise test was done with coaxial cable. Some improvement can be expected with the use of triaxial cable and proper grounding. It was the object of this test to observe only the operability and noise rejection capa-bilities of the amplifier.

The log N amplifier was tested for cable length variation effects.

The cable length was varied between 5 and 500 feet with 5 to 260 feet in -

RG-59 coaxial cable and the 500 foot length in amored triaxial cable. Three input current magnitudes (10 -10 , 10 -7 , and 10 -4 ampere) were tested. There was negligible attenuation for all cable lengths at all current magnitudes.

A violent cable vibration resulted in a worse case output voltage excursion of 50 mV peak to peak for all cable lengths at input current magnitudes of

-10 -7 The excursion at 10'4 ampere was negligible.

10 and 10 ampere.

A step input current was fed to the amplifier at various magnitudes for

, all cable lengths. For any particular input magnitude the cable length had negligible effects. It was noted, however, that ringing occurred at an input magnitude of 1 x 10 -8 ampere. This is underdamped as opposed to an overdamped

-10 -4 stability situation at 10 and 10 ampere input currents. To check this stability problem, a frequency response was nm for input magnitudes of 10 ,

-8 , 10' , and 10 -5 10 . The resulting data did not indicate a stability problem.

The log N amplifier was tested for temperature variation effects at varia-tions of 20 C from 25 C. The +20 C temperature variation produced a longer time constant by +25% for a 10 -10 ampere input step and produced a shorter b

d3 r

time constant by -3,3% at a 10 -5 ampere input step. The -20 C variation pro-

-5 i

duced a longer time constant by +2.2% at a 10 ampere input step.

'ite data indicated a change in output slope as the temperature was varied For a 10'# ampere input the -20 C variation had a 0.55% increase, and the-20 C

-11 variation had a 0.41% decrease. For a 10 ampere input the +20 C variation had a 2.0% decrease, and the -20 C variation had a 5.7% increase.

He temperature variation produced a change in signal-to-noise ratio from 50 at a -20 C variation to 80 at a +20 C variation.

4.3 BISTABLE TESTS The bistable amplifier was received, inspected, and calibrated according to BMC's instructions.

The bistable amplifier was tested for trip accuracy and retrip accuracy. -

The trip accuracy was 0.75%, and the retrip accuracy was 0.35%. The retrip may also be defined as the resolution, ne bistable amplifier was tested for intemal reference voltage supply .

variation. The voltage variation was 0.86% over a 20 C temperature variation.

The bistable amplifier was tested for response time, which was 26 ms for a 3.0-volt step.

The bistable amplifier was tested for the effects of temperature variation

( 20 C) from the nomal temperature of 25 C. The temperature variation caused -

a shift in accuracy of 0.75%. n e variation of the internal reference voltage supply because of temperature variation was noted above as 0.86%.

4.4 RATE-OF-CHANGE AMPLIFIER The rate-of-change amplifier was received and inspected.

The rate-of-change amplifier was tested for accuracy and repeatability (see Table 4.3). The accuracy, which along with the linearity is somewhat hard to define because of the signal noise present, was within 0.1%; the linearity was within 0.1%; and the repeatability was within 0.1%.

The rate-of-change amplifier was tested for time of response to various step input signal magnitudes. A 1 dec/ min step produced a response time of 0.8 second A 7 dec/ min step produced a response time of 1.0 second. A 99% value with the included noise made these measurements rather uncertain in tems of absolute values.

L e rate-of-change amplifier was tested for a temperature variation of 220 C from 25 C. The effect of varying the temperature was negligible.

The rate-of-change amplifier was tested for a foldover due to input signal overload. No foldover was noted for input signals up to 15 volts from 0 to 100 kHz.

4-4

~~

The rate-of-change amplifier was tested for a-c ripple on the d-c output.

l The ripple with the input of the amplifier grounded was approximately 1.0 mV.

The rate-of-chaage amplifier was testM for noise rejection. Figure 4.1 shows the graph of 20 log Ecut/Ein versus frequency in hertz. The 60-hert:

rejection is approximately -52db.

- 4.5 AUXILIARY POWER SUPPLY

.. The auxiliary power supply

• was received, inspected, and calibrated accord-ing to BC's instructions.

The auxiliary power supply was tested for a temperature variation of :t20 C from the nominal temperature of 25 C. The total voltage variation at 300 d-c volts for 5 C and 45 C extremes was 0.2 volt.

The auxiliary power supply was tested for linearity at 25 C over the design range of 15 to 300 d-c volts. Table 4.4 gives the recorded data. The data shows a test jack accuracy of 0.5% and a meter accuracy of 2.5%. The calculated

. data shows a maximum deviation in linearity of 0.16% over the operating range.

The auxiliary power supply was tested for a-c ripple on the d-c output voltage. The ripple was a 200 mV peak-to-peak signal riding the output of 300 d-c volts. SC was notified of this problem. An internal ground was probably at fault since the unit did function properly when received (see previous footnote).

The auxiliary power supply was tested for an output short circuit. When the output was short-circuited, the voltage dropped to :ero. hhen the short circuit was removed, the voltage returned to its set value. This provided a functional test of the limit reset.

.- 4.6 GRAPHITE PILE TEST No graphite pile (neutron source) test was conducted for the intermediate range.

4.7 LYtCHBURG POOL REACTOR TEST The intennediate range channel was tested on the LPR. The complete channel was tested as a system for foldover due to input signal c"erload. No foldover was noted when the detector current was increased above 1 x 10 -3 ampere. The detector power supply voltage did not vary during this increase of current.

The intermediate range channel was tested for response to power variation.

The equipnent responded well at all reactor power levels. It was noted that j ,

• The rirst auxiliary power supply unit received did not function. A reworked I

unit was received fran BC. This se::nd unit had a stability problem between

-240 and -300 d-c volts, hhen 5 0 was notified, they suggested an internal

!' grotmding problem on the oscillator board. Resc1dering some components cured ,

the stability problem, but the unit still had a no:se ripple problem.

s-5

an input current of approximately 4.0 x 10 ampere produced a log N amplifier d-c output voltage of 3.27 5 mV with a ripple of 5 mV and an oscillation of 1.6 mV in agreement with the laboratory tests. The rate-of-change amplifier output for the same signal was approximately 20 mV peak-to-peak variation (see Figure 4.2).

At an input current of approximately 4 x 10 -5 ampere the log N amplifier output voltage was 8.17 d-c volts with approximately 3 mV of oscillation. The rate-of-change amplifier output for this input level was approximately 150 mV peak-to-peak variation (see Figure 4.3) .

The noise rejection of'the channel was recorded as amplifier output noise present when the reactor is operating. Figures 4.2 and 4.3 show the amplifier

, outputs.

The cable length was varied between 70 and 520 feet, and the amplifier output was recorded at various input power magnitudes. The attenuation of the signal appeared as 8.0 mV (1.1%) on the amplifier output for 520 feet compared to that for 70 feet.

4.8 CCbMENTS Comments about the intermediate range channel are as follows:

1. Photographs and recordergraphs were taken of the ringing problem in the 10 -8 to 10 ampere range for .;tep inputs and noise spikes. The fre-

~7 quency response of the log N amplifier did not reveal any stability problem.

2. Photographs were also taken of the oscillation riding on the d-c output.

This same oscillation appeared on test jack #2 and did not allow proper balancing.

3. The response time of the rate-of-change amplifier was sufficiently fast to cause many bistable trips (3.0 dec/ min setting) during nomal reactor operation.

4. The testing personnel felt that the response time shouM be increased to allow a no-bistable-trip in a noisy environment.

5. As noted before, the tests were conducted with coaxial cable. Triaxial cable should help reduce noise interfarence.

6. Many minor problems associated with the prototype equipment such as solder joints, wiring, etc, were corrected with little difficulty.

7 BNC was made aware of the problems and our comments by phene liaison, by monthly progress reports, and by quarterly reports.

4-6

IABLE 4.3 IIATE-OF-CllANGE AMPLIFIIR .

Measured output Voltage, Meter Indication Remp input, volts /sec volts dec/ min Repeatability, %

slort circuit 0.909 0 <0.1 0.0208 1.818 1 <0.1 0.1040 5.454 5 <0.1 0.1456 7.272 7 <0.1 0.2080 9.999 10 <0.1 TABLE 4.4 LINEAlt1TY OF AUXILIARY P0h!ER SIPPLY I

Vmeasured, y V-V)x100 x 100, 1 Meter licading, volts volts test jack, volts m 300 300.0 3.000 0.0 253 250.0 2.499 0.04 201 200.0 1.999 0.05 150 150.0 1.499 0.06 100 100.0 0.999 0.10 51 50.08 0.500 0.16 41 40.00 0.400 0.0 20 20.03 0.200 0.15 15 14.97 0.149 0.5 O

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4-10

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1. ~

5.0 SOURCE RANGE TEST RESULTS 5.1 DETECTOR POWER SUPPLY The detector power supply was received, inspected, and calibrated accord-

- ing to BSC's instructions.

The detector power supply was tested for a temperature variation of 20 C from a nominal temperature of 25 C. The total voltage variation at 1200 d-c volts for 5 C and 45 C extremes was 1.0 volt.

The detector power supply was tested for linearity at 25 C over the

[ design range of 600 to 1200 d-c volts. Table'5.1 gives the recorded data, which shows a test jack accuracy of 0.33%. The calculated m w h = deviation in linearity over the operating range is 0.05%. .

l The detector power supply was tested for a-c ripple on the d-c output

', voltage. The ripple was a 5.0 mV peak-to-peak 7150 H: signal riding the d-c I output of 1200 volts.

The detector power supply was tested for an output short circuit. hhen f the output was short-circuited, the voltage dropped to :ero. hhen the short circuit was removed, the voltage retumed to its set value. This functionally li tested the limit reset.

5.2 COU.NT RATE AMPLIFIER AND PREAMPLIFIER TESTS

, The source range (SR) preamplifier and count rate amplifier were received, inspected, and calibrated according to BMC's instmetions.

The SR preamplifier and count rate amplifier were tested for their sensitivity

,_ to charge input at various preamplifier gain settings. The pulse generator output pulse was fed through a 10 pf capacitor producing a charge. With a discriminator dial setting of 2.0, the 10 kH: pulse height was decreased until there was a loss of count rate amplifier output. For gain settings of x2, x4, x10, x20, and i x40, the minimum pulse height was 240, 160, 90, 60, and 40 mV in that order.

For discriminator settings of 1.0 and gain settings at x2, x4, x10, x20,

and x40, the minimum pulse height was 150, 180, 36, 36, and 13 mV in that order.

I The SR preamplifier was tested for pulse pair resolution. The generator 7

pulse must have rise and fall times of 20 ns or less, and the pulse width must i be less than 100 ns. The pulse amplitude also is a parameter. With a gain of x2, and x40, the pulse pair resolution was 110 :10 ns.

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The SR preamplifier and count rate amplifier were tested for accuracy

< and linearity. The tabulated data in Table 5.2 shows an accuracy of 2.3%.

The tabulated data shows a linearity of 2.34%. The accuracy and linearity are affected by the poor resolution, the pulse generator frequency and the initial calibration.

.. The SR preamplifier and count rate amplifier response time was recorded for decade step changes in the pulse generator frequency. For decade steps of 1 2 2 3 3 4 4 5 5 6 10 to 10 , 10 to 10 , 10 to 10 , 10 to 10 , and 10 to 10 pps, the response was 50 seconds, 20 seconds, 5 seconds, 2 seconds, and 1 second in that order. The 99% response time was difficult to detemine acculately. Also, the frequency was not absolute.

The SR prearplifier output pulse was recorded for different magnitudes -

4 of gain setting with a 10 pps nonsaturation condition. With the gain at x10 the rise time was 20.0 n sec and the fall time was 400 n sec. With the gain at x40 the rise time was 60.0 n~sec and the fall time was 350 n sec.

The SR preamplifier and the preamplifier plus count rate amplifier signal-to-noise ratio were tested for minimum and maximum gain settings. The signal-to-noise ratio for the preamplifier at x2 and x40 gain was 66 and 25 respec-

" ~

tively. The signal-to-noise ratio for the preamplifier' plus count rate amplifier at x2 and x40 gain was 7030 for both gain settings.

H e SR preamplifier and count rate amplifier were tested for the effect of connecting cable lengths. The photographs in Figure 5.1 show the effects of varying the cable length between the pulse generator and preamplifier.

.. The conditions were as follows:

1. Generator at 10,000 hert:: output fed through a 10 pf capacitor into the preamplifier

2. Input signal tapped at the preamplifier input and scope unloaded f'

3. Preamplifier output fed to an unloaded scopc.

The cable length was increased from 1.5 to 202 feet. He delay, atten-uation, and reflection were recorded. The effects of a mineral oxide ,

cable are also shown in Figures 5.1.

The RG 59/u cable with lengths of 1.5, 60.0, and 202 feet produced input delays

. of 4.0,100, and 330 ns in that order, and an output attenuaticn of 0.2 volt for a 202-foot length. .N*ote the effects of the input reflections on the output sig-nal for a particul:ir cable length.

5-3

A 20-foot length of mineral oxide cable vas tested. Also tested was a combina-tton of 20 feet of mineral oxide and 60 feet of RG 59/u. The input attenuation for both configurations was more severe than that for plain RG-59/u. The mismatch at the junction of the two cables seemed to cancel any large reflec-tions in centrast to plain RG-59/u, also, this mismatch produced the most attenuation of all ccnfigurations.

Nith the input signal cable from the preamplifier fed into the count rate amplifier and the signal tapped at the input of the count rate amplifier with an unloaded scope, the cable lengths were 5, 60, 202, and 500 feet. Excluding

, the 5-foot reference length, these lengths produced attenuations of 50, 150, and 200 mV for 60, 202, and 500 feet in that order. No other effects were noted.

The SR preamplifier and count rate amplifier were tested for interference noise. With 60 feet of RG-59/u cable between the preamplizier and count rate amplifier, a soldering gun was held adjacent to the cable and switched on and off . The resulting parallel-induced 60 hert: caused a 10 mV, 60-hert: signal

, to appear at the output of the count rate amplifier.

A 60-hertz, low-impedence source was then fed directly into the preampli-fier. With the input' magnitude between 2.0 and 10.0' volts peak to peak, the resulting count rate amplifier output was a randomly spaced 10-volt, peak-to-peak, narrow-pulsed signal.

The SR preamplifier and count rate amplifier were tested for the effect of temperature variation of 20 C from a nomind 25 C. The temperature varia-tion had little or no effect on the rise and fall times of the preamplifier.

The temperature variation also had little or no measurable effect on the response time of the count rate amplifier. The accuracy of the count rate amplifier due to a +20 C temperature variation from the normal value of 25 C was 1.0% or less. The accuracy due to a -20 C temperature variation from the nonnal value of 25 C was 5.5% or less.

The linearity of the count rate amplifier was 6% or less at either +20 C or -20 C variation from the nonnal value of 25 C.

The pulse pair resolution of the preamplifier at 0 C and at 60 C was less than 150 ns at a gain setting of x2 or x40.

5.3 BISTABLE TESTS j The bistable amplifier was received, inspected, and calibrated according to BMC 's instructions.

l 5-4

~~

The bistable amplifier was tested for trip accuracy and rstrip accuracy.

The trip accuracy was 0.44%, and the retrip accuracy was 0.64%. The retrip accuracy may also be defined as the resolution.

The bistable amplifier was tested for internal reference voltage supply

- variation. The voltage variation was 0.15% over 20 C temperature variation.

The bistable amplifier was tested for response time, which for a 3.0-volt step was 26 ms.

The bistable amplifier was tested for the effects cf temperature variation

(::20 C) fra the normal temperature of 25 C. The temperature variation caused a shift in accuracy of 1.9%.

! The temperature variation on the internal referenced voltage supplies was noted above as 0.15%. -

J 5.4 RATE-OF-CHANGE AMPLIFIER The SR rate-of-change amplifier was received, and inspected. The rate-of-change amplifier was tested for accuracy and repeatability (see tabulated data, Table 5.3). The accuracy was less than 0.1%, the linearity was less than 0.1%, and the repeatability was less than 0.1%. These measurements were s mewhat hard to define because of the amount of signal noise present.

The rate-of-change amplifier was tested for time of response to various step input signal magnitudes. A 1 dec/ min step produced a response time of 4.0 seconds. A 8 dec/ min step produced a response time of 4.0 seconds. A 99% value with the included noise made these measurements rather uncertain in terms of absolute values.

.. The rate-of-change amplifier was rested for a temperature variation of i

,. 20 C 'from 25 C. The effect of varying the temperature was negligible.

The rate-of-change amplifier was tested for foldover due to input signal overload. . No foldover was noted for input signals up to 15 y from 0 to 100,000 hertz. The rate-of-change amplifier was tested for a-c ripple on the d-c output.

i The ripple present with the amplifier input grounded was approximately 1.0 mV.

The rate-of-change amplifier was tested for noise rejection. Figure 5.2 shows the graph of 20 log Eout/Ein vs frequency in hertz. The 60-hert: rej ection is approximately -52 decibels.

5.5 GRAPHITE PILE TEST

> The SR preamplifier and count rate amplifier were tested using a graphite i

,_. pile neutron source.

5-5

TABLE 5.3 TEST OF RATE-OF-CHANGE AMPLIFIER V

Ramp Input, measured, Meter Indication, Repeatabilny, volts /sec- volts dec/ min  %

., short .909 0 <0.1 0.0238 1.818 1 <0.1 0.0952 4.545 4 <0,1 0.1904 7.272 8 <0.1 0.238 9,999 10 -

<0.1

I l

• l 1

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1 5-6

The preamplifier and count rate amplifier were tested for response time by removal of a cadmium sheet from around the detector. This particular respcnse is for the detector through the count rate amplifier. For a 2,800 to 8,000 hert: step, the response time was approximately 6.0 sec. For a 38,000 to 83,000 hert: step, the response time was approximately 1.0 sec. Absolute values are difficult to find using the 99% value.

The preamplifier and count rate amplifier sensitivity was tested by varying the preamplifier gain with the detector stationary relative to the neutron source.

With the discriminator dial at 1.0, gain settings of x2, x4, x10, and x40 produced count rate amplifier outputs of 0, 0, 2.75, and 3.50 volts in that order.

The preamplifier and count rate amplifier were tested for cable length .

effects. As the cable length between the preamplifier and count rate amplifier was varied, the d-c output of the count rate amplifier was recorded. With the 60-foot cable as a reference, the decreases in amplitude for 202 and 500 feet

~

were 80 mV and 200 mV in that order.

The SR preamplifier and count rate amplifier were tested for interference

• ~

noise. The results were similar to those described in section 5.2. The only addition was the use of a small a-c, high-speed motor (for an electric eraser) to create noise. The resulting increase in the count rate amplifier output was 0.4 volt.

5.6 LYNCHBURG POOL REACTOR TEST

, The source range channel

• was tested as a system using the LPR as a neutron source. Count rates for random and unifom inputs can be seen by comparing data on the graphs in Figures 5.3 and 5.4.

The input signal was increased until the count rate was saturated. hhen signal was further increased, no foldover of the amplifier output was observed.

The count loss of the system was plotted in Figure 5.5. The plot gives a count loss of 38% ct 100 pps and less than 1% at 105 pps.

The cable length between the preamplifier and the count rate amplifier was

.- varied from 50 feet to 500 feet with a 10% decrease in count rate amplifier d-c output at low count rates and approximately 3% at high count rates. (This test

.,, was conducted with all conditions remaining constant while only the cable length was varied at any particular count rate.)

l The initial lab test and graphite pile test did not reveal the problems of the l preamplifier and count rate a=plifier. It was only during the LPR test with a Jarge random count that these problems were apparent. (The data given is l for a working model.)

5-7

The cable length between the detector and the preamplifier was varied from 20 to 100 feet with a 6.2% decrease in count rate amplifier d-c output at a low count rate. (This test was conducted with all conditions remaining constant while only the cable length was varied. Some small error may be introduced with each repositioning of the detector.)

The noise interference was a combination of type, location, type of cable, and grounding. Therefore, the results of the test are given as:

1. Coaxial cable allows more noise to be introduced than triaxial cable.

2. Armored triaxial cable with the armor as the triaxial shield and the two inner shields tied together is better than plain triaxial cable.

3, Large induction motors switching on and off cause the most severe voltage excursion; small noisy motors only insert a nuisance noise at a .

constant rate with no excursion.

4. Noise introduced between the detector and preamplifier is most severe since it is also amplified.

5. Low count rates are most susceptible since at low rates a noise burst is relatively important.

6, Only one earth ground should occur, preferably at the power supply.

~

5.7 PROBLBfS Problems associated with the sy: stem were as follows:

1. Too long a fall time occurred on the preamplifier output, thus not allowing a high count rate.

2. The count rate amplifier was loaded down when equipment was plugged into the scaler output jack.

3. An internal grounding problem allowed a pulse to appear on the count rate amplifier d-c output.

4: The scaler cutput pulse had too long a rise time to allow a high count -

rate.

5.8 C05tDTS Comments about the source range channel are as follows:

1. The present rate-of-change amplifier response time was sufficiently fast to cause many bistable trips (at a 3.0 dec/ min setting) during normal reactor operations.

2. The testing personnel felt that the response time shculd be increased to allow a no-bistable trip in a noisy environment.

5-8

3. The testing personnel felt that triaxial cable should be used to help reduce noise interference.

4. Section (5.7) mentions problems associated with (1) internal ground of the count rate amplifier, (2) scaler output jack loading effects, (3) preamplifier output pulse fall time, and (4) sclaer pulse rise time,

5. Many minor problems associated with prototype equipment were corrected

. with little difficulty.

6. 30 was made aware of the problems and our comments by phone liaison, by monthly progress reports, and by quarterly reports. The majority of these problems have been corrected.

9 9

4

• e 6 e O

9

• 9 4

4 .

6

• l ..

k 6 h l .

5-9

FIGURE 5.1 VARIATION OF CABLE LENGTH l

I I

I l

. PHOTO A

~' '

i X = 500 ns/cm l.....  ; . . . . . . . . ! .. . . . . Y = 5.O mV/cm _

l Preamplifier Input With, 1.5 Feet of RG-59/u i

^

j N ._

e .

! PHOTO B -

l r X = 500 ns/cm I

Y = 5.0 mV/cm _.

!, Preamplifier Input With

, 60 Feet of RG-59/u e

5-10

l -

, s.1 i

L :a .;.gg .g 4p -

@ PHOTO C P

j" j

g - '-

y.-

7 :h. h; h4 wfk X = 500 ns/cm

i. [.j, [, ~ g K.;

- .. < w

< p'.{kd ,ys"*w[ a.. ,

U i-)(

.A.

~%w Y = 5.0 mV/cm Preamplifier Input With F' :cfL.m( ' ?J .. @. ,, ..L ,7_

m . ..+, '

. . , - .4 . . W}*.s.

. * ;,m44, u

.4.m .. 4e .aj ~ . .-; g.,;. , ..jy;,

r-

<A L.1'.[,n...Jj ty . 202 Feet of RG-59/u

. a.g . - .

7,  ; ~ . ; s. 4 %. ' ? u '.A -

[f . .ifR.4:- .2f..?u.e -g[ .

L  ;  : .

i .> . :*. , . 4+.g, 3, . .pty 7,_,..  ;

., t

,' g, ,'4.fy,

-. .g . <, v, Ye I,;,. .a$.6, -

.g > :, ; .

ju- y

' r- . 4; n. .o. w .yQ , ..e,- .s~

., ;;,* 9 ? , c , _ . , 4%

.

i y' : - - ' yn . Tr. 5 ,

y l t h. 5 4. . A L

.4 l'

, L l r '

l )

L .

r  :.---

PHOTO D

.g 9,gg..;-[ p .. p.g? gg. 943y ' ' ,';

rM. c% ; y;g y.

,= j g.7.

r

.. ~ g gao +a - -:. ; ps

1. ., *m . ., #g-Q A X = 500 ns/cm r, < . :.m. ,1 e -

. r.aa-w+. ,g - .

y. .~f

f. 9.f , y, .. . . '-> . ~ -.- <

3. Y = 5 mV/cm

-, y .+ . v.

., ..- .e

. M:

e,

. . ' n rty ^: .-

Preamplifier With 20 Feet 3 r ., 4 kn:jf.F ;l..'... }?- ..

? y. .i M, :g:.):g M. . .; 14,. . ;y ;g*A g of Mineral oxide cable

'$ ~ , ..

r, , 1 -

'* v -

.v.'f:V . - : n J'8 D a .w b L  ; - p, 'l"=,-., g. i,. ' f' . . #% ;[

• 4*2.} .g.4x.?w m -

.f f.

..u-i M * :, , f . y 'i , Y/ * * . I r ' 'gs .' ,

.w ,.

.m . t[: .' ' . - '.4 w g Q ,g ,; l a,.3a ,  : P#

.5,. at. +_

l.. .~..

-~ .

m m.:.. m..  ;..: ;y7a.yw(-K

...-+2 -c

~j {:

k- ,f,A++. .

,4. can ,

f'-; , A*4 :l q c:s .#w- 4. -.g' dgp;!

r.

I L

l 5-11

- - - . . . - - - - ,_,,y .. __ ., __ _ _ _ .

i

\ . < '

l \

PHOTO E l .

, X = 500 ns/cm U Y = 5 mV/cm

{

i Preamplifier Input With 20 Feet l, ....-. _ _ _ ;.. .~ - . ,

of Mineral Oxide Plus 60 Feet t

l _

of R2-59/u I

a I

l

, I i

PHOTO F

- l X = 200 ns/cm Y = 1.0 V/cm Preamplifier Output With l' ~~ '

1.5 Feet of RG-59/u Input Cable T'~

1 m

5-12

u L

g.e gf&~ j . Wf[$ . 3Q, *- PHT O G h' f' gN.f%

p

• '? 2+-.

.f d AAl ,,?

L , '

' ;g A at+k.'. % [?:l r3

>ri

A#. . , v g.p. '.i 7 ; g, . y* 'v.i. ; y'A.< "',

>J .

X = 200 ns/cm

s ,. g.... . z. .

_ 6: .+

l

' ?. s v ,~ y. i, ., l ' 'f l .( .

• p,. ,

, r

'.1. ' te. :.E Y = 1.0 V/cm P h, w,54....n..' ps '. A..";2/l ,..~4*.

. .,q . . . - . .... ,,. . J. ~ . . ; ' *" T, "g Preamplifier Cutput With 60 Feet

'y c pr ,[.5' .

r,'. , , I

~

i of RG-59/u Input Cabic

=

• -* ) x ;;. .:4

& f

. ' . . .4 . . . , -

p . .f9

r.  :):.$.')y'_.l.bg.Qigz., . - w. ~j;fL .. s ,

Y

. 4,,g.4r,>[;

1, f'4 fw4 , ym

%. 4. .

4.

.%5 f,4,.l 'q jg, .c .. y -)

i

, ' y f ;'; ** < '

~

P, . ..;. . ./ .i hIk '

L r~

L.

f' ,

i I.

4 i

r' L

! L. E"" Phar 0 H Ja% Q (. gf * #O gM. ;f- Ap@ipC *.ch::h, 7,. g '

Op %y ,,h' }  %%.g~

' F'

.-' .T.;

• f: y

. X = 200 ns/cn

• --  :". ,:~ - f{ '.j;d i

g -'..... i. !f Y = 1.0 V/cm

w. .e .

. +

..e . eg Preamplifier Output.With 202 Feet

, 4~&.

.f-g, t -

..,a,6, 9s.;sm tp p 'a y' x ,..

4. :

.f p(f ?i*;'if ;;k.-ff7 W . l ..,aQ'-

L of RG-59/u Input Cable

<, .,. .f{ - -Q I l [h((, .%n" . .

. . 5% ,

y

. i*.5 s 9. 3; :.-L 3 - g yw* k,r- . ,

.;.9.'py;l

.0

," . .!.'.*e , ' ye c',

,-i... +',,. g g,.

. ,3 ,

. e .: ,. .

, y ':_A r* -

• 3 4,e / .4; Y , ", r. . -'

. %.j'*A

.,' %Q  :. ,:

. . n .-. . g. . . ;+. ,,JY.~~,...<g.e l .

(. ;,. +7 v . -

.' .'.. f., e.;'. p Q,

..4, ' '. .

u,.t .

fdmIh?f 7.; S h ' k N ' ' ' e Z l- 9 4 l<

t i k 1

5-13 m

.-._.,_, _. . _ ._ - ., _ _,,,, ,,. y . ,._, _ . , - . . , _ , - . , _ _ _ . , , . , . , , - -

(

5 o o

u . o u

9 m

e e

~

o e m

ce O

/

2 O0 S C U s

b E O /o f D

~

h / . c O'0 2 f $

$ 0 - - 5 E

B m

E

& s

@ O -

o a.

N. I w 1 l

l O

- I  ! I f .

o o o o o o o 7 7 7 7 7 7 2

SIG9T08P 'utE/ noE Sol 02 1

i 5-14 I

~

FIGURE 5.3. RANDO! INPUT (pps) vs. d-c l'JLTAGE OUTPUT OF THE COUNT RATE A\1PLIFIER 0

< 10 n

O t e F*

• - O s /

. . 10 _ o

/

O

/ .

/

..  ; j

- O

.. u w

s.

O

/

8 /

s. U O

O 4 '

s. 10 _

.. O

. . g

& O a

5 O

/

e o'

,/

s. Ol 3

,- 10 _

.. O

.~

.m 6, 4 0

, /

10' I  !  !  ! f f 4.0 5.0 6.0 7.0 8.0 9.0 10.0 l~ . Count Rate .haplifier Output, volts 5-15

FIGURE 5.4. UNIFOPM INPUT (pps) vs. d-c VOLTAGE OUTPUT OF THE COUNT RATE A\tPLIFIER 10 6 o 5

10 _

0 h.

E.

t 6

5 E

> d 4 -

s. 10 _.

.2 h

"c.

4 3

a 2

5 u

10 o i

10 I ' '  ! f

_o 4.0 5.0 6.0 7.0 8.0 9.0 10.0 Ccunt Rate A plifier Output, Volts 5-16

FIGURE 5.5. COUNT LOSS CURVE FOR SOURCE RANGE CR\NNEL 0

10 p

.- /

ol

/ n.s&

. O o

3 10 _

o/ .

, - . 0 10 _

1 O

• - 5

'~

• /

w .

'~m E

O

/

j 3 /

/

10 - o I i

.. o

. /

,, 10 _

m

- t I f f 0.1 1.0 ~ 10 100 1000 10,000

. Arbitrary Units of Pcwer 5-17

6.0 SOURCE AND IhTERMED'IATE RANGE TEST CIRCUITS The source range and intemediate range test circuits were received, in-spected, and calibrated according to BIC's instructions.

The source range test circuit was functionally tested at each switch posi-tion. The response of the source range chreinel.was recorded. All functions agreed with the desired values within an accuracy of 1% or less.

The intennediate range test circuit was functionally tested at each switch position. The response of the intemediate range channel was recorded. All functions agreed with the desired values within an accuracy of 1% or less.

The power range test circuit was not received.

O a O

6-1

4

• 7.0 ADDITIONAL CO.MENTS

.. t Figure 7.1 shows the interconnection of the system and its effect on the

, detector power supply and auxiliary power supply. The small difference in I frequencies of the detector power supplies caused a modulation. (The oscilloscope i - was capacitive coupled by a 0.01t.F capacitor,) This intemodulation may have been j- a cambination of different frequencies, or the grounding of the system was not

. adequate.

,_ Figure 5.1 shows the effect of varying the cable length between the pre-

',, amplifier and detector. If the fall time of the preamplifier pulse is decreased sufficiently, then the cable reflections will'be counted as a true pulse. Also, if the fall time is increased, high count rates are impossible. -

9' r.,

f'

! 6.

s- ,

L.

e 9 a f'

4.

0 4 a

4 e 4 *m l

71 J

f i

l FIGURE 7.1 INTERCONNTCTION OF SYSTBI

;n , di

! - { . ( *A :.g [, w a.n.f* .f :6 W.Rn.

.;'4.. . %fj p

4. 6 4,,

u.

?- w p (_ + ; e

.fa*t.[

1 PHO'ID A

, 7

....; . -4 ], ' %+$,;;p y.(.

l I

l} .. , e (5 ,.y

. ,- l- } g] .g ..l c.. q. = y X = 10 ms/cm l 44 5 ,

.Tg =J 4

t .

y . , p. > Y = 20 mV/cm '

. [,p.M,g,g

-4 e A 4-lg

g. :.3 -.

7 5 . k hg g .gt Source Range Detector P. S. Conditions:

?

[S

. .l , J 7 ,

t  % PR Det. P. S. off xy 1 IR Det. P. S. on

-a

'd.,.,+..

.; .v5 4, ,2 p.. . ygv z.g. ~; .Me /. 2

g. ; . v.

y u%, M+ . '.: .:.;. ~

c. 1.t

.. . 3 , *4s'..

V

c.,q, b e.e, i; //

IR Aux. P. S. on I i l

' % . .;% s ? W r "

. tcc : 3 7 ,i w .  ; SR Det. P. S. .on

.=

't - ,7.. . ,

' . .r*. *, p-fs - S _

~

l I

' [fT' u %%at.

,)j TI(*# ') ',h[k.D I -

4 .'

g ; ..f37 % 4 ="'

9, ;W. . ,

k. . y +,.. - n.i A*-% y

'M - -

a * . -- .%

e....y.,,=r-.

,-l - * # s$. n & .

g -n@ A 7, '

( .

PHOTO B

._.-,,.,s . -

c s n

. ,,  ;

,- 77Q -l.

%,i '

, '. ,,~ , -. . ,; X = 10 ms/cm x ,n

, - - -4.e X,+ 'T - /  : .. .

^i 3..' .-' W -

Y = 20 mV/cm

-v p 's

+ . .>

n wz Source Range Detector P. S. Conditions:

[j..) $.. .' . 4 ' ;" " . ". . . .. .

M

<-l . A -Q

-( PR Det. P. S. off

- [h((gyn w- [,, ,.h.lfk"[. "

M n:% .7

. e g.4.3.

5 c .c v . 3y E.' i IR Det. P. S. on f: . .. '.,. M..) .'y . ; ey 9 .J.w ,-Lj tp, .;

IR Aux. P. S. off

u N, ; . * .. f; v . , ;.; $.

Q SR Det. P. S.

on

{; ..

, ' y.9 '..,' . ". , ?;;.y- Q,j.j,y ;

• l "y id p -Q10-y :: w 9 ;% ,  %

l l

1 F

I 7-2

m . .

J n

PHOTO C p.,4 w .

b..hh,n.> . . . .~ .: ,

.h

w..h.

, a, V3 :r<- '3.. . ..,.> g.: :.,J.. ~ .9 Q "a, . u?.  ? Y - 10 ms/cm

.4 # p' . . M r;n. . . . . '. ; : . .%a- .,,. %. g.3 .m e "

,7 Y = 20 mV/cm

. /e .4 %_ . , ' . .< 4

- e.4,,. Qt .$

d 3,

,1 y . 5.g,kt$ :F y .. .- . .. c.- Intermediate Range Detector P. S.

a .".?

g:. ;-1 4 i

r :r.;4U. .. Conditions:

% y, .-

j n 1. gg , . .

s

.75 k PR Det. P. S. off

.4 [?. Q; L h, r,'L,flt-s

~

SR Det. P. S.

, - . . g .c *y ,: c -

'Wg on l

I

{

%$,f ..']

2~ -

q/,hjij:.,;.4.' ,

t . , '., ,

IR Det. P. S. on u - ; .. Q - .@ x ,by IR Aux. P. S. on

./ gp .

. O n l

1 L

r > .

l L

87 .

I u

g~ ': , . g. - ef; C. g Q if y.':*-Q y' y Q ,

i 6 7_ ...-

Fr*Dr0 D p .>

u v.4,;..- y .: - qs %,-,.y..n . o. p: # ,. .,4r y

.%.g+.

.I wg.3

.g y;_ '.  ?*;,y_f g _';;.u;q; ..

.5 ..by[; x. 10 mgjc2 r, _s - - .

g .

.e  ; ..

'; bi j .= a

r . c c g.

u i

1 A.:d A w ., .J .; . .;. .

E .e . %. 7 . .. ,

Y = 20 mV/cm

.f..

Intemediate Range Detector P. S.

5, 3% , g .. . ^t  ; ,j 5.h..I.. :.p.d, ... g.h .. .h!d/ . : .. Conditions:

!" L, ;29859888%g .

6 .,."h.k I%.h; ' $

• • o t " s-SR Det. P. S.

l p> 4 eye 3- . .

d.. , . 5.,; .

... ,. on r,.

L m?g ..j.n , 7, 4 -. . +% g, .. . _ .

y IR Det. P. S. on n , , . ~p

_ , e/

fsy . IR Aux. P. S. off

• ,,.. .# ws . g.. : . . 3

.'. ', Tt; M y f; -'

• A P' ,4 , .

}., G -  :.A V.k' y, . . . +). 9 g. 4_ yL;qq_, Q. f.

n.

1.N w

I 7-3 1

l .

~

o l

l PHOTO E X = 10 ms/cm Y = 20 mV/cm Intermediate Range Detector P. S.

et P S. on SR Det. P. S. on IR Det. P. S. on IR Aux. P. S. on PHOTO F X = 10 ms/cm Y = 20 mV/cm

' ~ ~ ~ ~

Intermediate Range Detector P. S.

~

, j Conditions:

. . L': '_.I PR Det. P. S. on

, SR Det. P. S. off IR Det. P. S. on IR Aux. P. S. on 7-4 ww-=r e_=r -w w , _-.. _ . _ _ _

- . _ _ _ , - , - , _ _ , _ _, _ _ _, _ _ _ _ __ _____ _ __