Last Updated: 05/05/2025 1:34 AM
The following table lists all the components that make up the document.
Replace NHA-472 (neutron high voltage board) on PRM-470 CGN.
Prior to arrival, notify operators concerning expected work and duration.
247 - 214 - Pregătirea instrumentului pentru operare; Remark:
257 - Demontați instrumentul
Demontați instrumentul
397 - 313 - Opriți instrumentul; Remark:398
313 - Opriți instrumentul
Opriți instrumentul
398 - Apăsați butonul POWER (Alimentare) până când afișajul ...
Apăsați butonul POWER (Alimentare) până când afișajul se stinge.

261 - 65 - Deșurubați cele patru (4) șuruburi ale capacului; Remark:264
65 - Deșurubați cele patru (4) șuruburi ale capacului
Deșurubați cele patru (4) șuruburi ale capacului
264 - Folosiți o șurubelniță Phillips (PH2). Șuruburile nu trebuie îndepărta...
Folosiți o șurubelniță Phillips (PH2). Șuruburile nu trebuie îndepărtate complet.

263 - 262 - Îndepărtați capacul instrumentului; Remark:413
2771—Notă : În interiorul instrumentului există plăci de circuite imprimate de înalt�...
În interiorul instrumentului există plăci de circuite imprimate de înaltă tensiune; cu toate acestea, ele transportă curent cu o intensitate foarte mică, ce nu reprezintă un pericol pentru sănătate.
262 - Îndepărtați capacul instrumentului
Îndepărtați capacul instrumentului
2734 - 266 - Locate battery connection; Remark:2733
3033 - Note : PRM-470 CGN models have an additional board and connectors not shown in remar...
PRM-470 CGN models have an additional board and connectors not shown in remark images.
266 - Locate battery connection
Locate battery connection
2733 - Battery connection is labeled 1.
Battery connection is labeled 1.

271 - 270 - Deconectați bateria; Remark:414
1345—Notă : Este o bună practică inginerească să vă asigurați că toate cablurile �...
Este o bună practică inginerească să vă asigurați că toate cablurile și toți conectorii sunt etichetate înainte de deconectarea lor.
270 - Deconectați bateria
Deconectați bateria
2737 - 2736 - Disconnect NHA-472 board wiring; Remark:2735
2736 - Disconnect NHA-472 board wiring
Disconnect NHA-472 board wiring
2735 - Remove connectors at locations 5, 6, and 7.
Remove connectors at locations 5, 6, and 7.

2739 - 2738 - Remove faulty NHA-472; Remark:
2738 - Remove faulty NHA-472
Remove faulty NHA-472
2742 - 2741 - Locate NHA-472 board; Remark:2740
2741 - Locate NHA-472 board
Locate NHA-472 board
2745 - 2744 - Remove NHA-472 mounting nut; Remark:2743
2744 - Remove NHA-472 mounting nut
Remove NHA-472 mounting nut
2748 - 2747 - Remove NHA-472 board; Remark:2746
2747 - Remove NHA-472 board
Remove NHA-472 board
2746 - Gently pry up each side and lift.
Gently pry up each side and lift.



2750 - 2749 - Install new NHA-472; Remark:
2749 - Install new NHA-472
Install new NHA-472
2753 - 2752 - Mount new NHA-472; Remark:2751
2752 - Mount new NHA-472
Mount new NHA-472
2751 - Verify connectors are correctly aligned then press down.
Verify connectors are correctly aligned then press down.


2756 - 2755 - Reinstall mounting nut; Remark:2754
504 - Caution : Do not overtighten the mounting nut.
Do not overtighten the mounting nut.
2755 - Reinstall mounting nut
Reinstall mounting nut
2758 - 2757 - Reconnect wiring; Remark:
2757 - Reconnect wiring
Reconnect wiring
2761 - 2760 - Reconnect all connectors except battery; Remark:2759
2760 - Reconnect all connectors except battery
Reconnect all connectors except battery
2759 - Do not connect location 1.
Do not connect location 1.

2766 - 2764 - Adjust neutron high voltage; Remark:
2765 - Note : The same circuit boards are used for both gamma and neutron detectors; howeve...
The same circuit boards are used for both gamma and neutron detectors; however, the neutron detector board NHA-472 requires different voltage adjustments.
2764 - Adjust neutron high voltage
Adjust neutron high voltage
2770 - 2769 - Determine manufacturer of the neutron detector; Remark:2767
2769 - Determine manufacturer of the neutron detector
Determine manufacturer of the neutron detector
2767 - To access the neutron detector information, remove the moderator from the cas...
To access the neutron detector information, remove the moderator from the case and slide the neutron detector out.


2768 - Detector information is printed on the detector. There are two (2) common neu...
Detector information is printed on the detector. There are two (2) common neutron detector manufacturers: GE Reuter-Stokes and LND. RS indicates GE Reuter-Stokes.

2772 - 220 - Power on instrument; Remark:228
2771 - Note : There are high-voltage detector circuit boards inside the instrument; however...
There are high-voltage detector circuit boards inside the instrument; however, they carry an extremely small current that does not pose a health risk.
220 - Power on instrument
Power on instrument
228 - Press POWER button until the display turns on.
Press POWER button until the display turns on.

2777 - 2776 - Connect HV probe to DMM; Remark:2774
2776 - Connect HV probe to DMM
Connect HV probe to DMM
2774 - Use Fluke 80K-40 High Voltage Probe and Fluke 179 DMM. The GND tab should lin...
Use Fluke 80K-40 High Voltage Probe and Fluke 179 DMM. The GND tab should line up with the COM position.

2658 - 2566 - Switch DMM to DC voltage; Remark:2613
2566 - Switch DMM to DC voltage
Switch DMM to DC voltage
2785 - 2567 - Locate ground test point; Remark:2782
2567 - Locate ground test point
Locate ground test point
2782 - The neutron ground TP38 is located on the NHA-472 neutron board and might not...
The neutron ground TP38 is located on the NHA-472 neutron board and might not be clearly labeled.


2790 - 2789 - Connect HV probe to ground; Remark:2787
2789 - Connect HV probe to ground
Connect HV probe to ground
2787 - The ground connector for the HV probe may be directly connected to the ground...
The ground connector for the HV probe may be directly connected to the ground test point.

2788 - It may be easier to use a separate test lead (jumper wire) and connect the HV...
It may be easier to use a separate test lead (jumper wire) and connect the HV probe ground to the test lead.

2794 - 2792 - Locate high voltage test point; Remark:2791
2793 - Warning : The test point has high voltage. Only contact the test point with the high vo...
The test point has high voltage. Only contact the test point with the high voltage probe.
2792 - Locate high voltage test point
Locate high voltage test point
2791 - The neutron high voltage TP34 is located on the NHA-472 neutron board and mig...
The neutron high voltage TP34 is located on the NHA-472 neutron board and might not be clearly labeled.

2797 - 2796 - Contact HV probe to test point; Remark:2795
2796 - Contact HV probe to test point
Contact HV probe to test point
2795 - Contact TP34 (not labeled) with tip of red HV probe.
Contact TP34 (not labeled) with tip of red HV probe.

2874 - 2873 - Locate neutron high voltage adjustment; Remark:2872
2873 - Locate neutron high voltage adjustment
Locate neutron high voltage adjustment
2872 - R10 on the NHA-472 neutron board is used to adjust the high voltage for the n...
R10 on the NHA-472 neutron board is used to adjust the high voltage for the neutron detector.

2885 - 2881 - Adjust neutron high voltage; Remark:2875
2884 - Standard : High voltage for a GE Reuter-Stokes neutron detection is 990 Volts. High volt...
High voltage for a GE Reuter-Stokes neutron detection is 990 Volts. High voltage for a LND neutron detector is 1075 Volts.
2881 - Adjust neutron high voltage
Adjust neutron high voltage
2875 - Use precision slotted (tweaker) screwdriver to adjust R10. The voltage should...
Use precision slotted (tweaker) screwdriver to adjust R10. The voltage should match the manufacturer’s recommendation.
GE Reuter-Stokes: 990 Volts
LND: 1075 Volts

2878 - The number indicated on the DMM must be multiplied by 1000 if the Fluke 80K-4...
The number indicated on the DMM must be multiplied by 1000 if the Fluke 80K-40 probe is being used.

2889 - 2888 - Remove HV probe leads; Remark:
2888 - Remove HV probe leads
Remove HV probe leads
2893 - 2892 - Locate neutron stage 2 gain adjustment; Remark:2891
2892 - Locate neutron stage 2 gain adjustment
Locate neutron stage 2 gain adjustment
2891 - R17 on the NHA-472 neutron board is used to adjust the stage 2 gain.
R17 on the NHA-472 neutron board is used to adjust the stage 2 gain.

2896 - 2895 - Set stage 2 gain at maximum; Remark:2894
2895 - Set stage 2 gain at maximum
Set stage 2 gain at maximum
2894 - Use precision slotted (tweaker) screwdriver to rotate R17 10 full turns clock...
Use precision slotted (tweaker) screwdriver to rotate R17 10 full turns clockwise.

303 - 302 - Reasamblați instrumentul; Remark:
302 - Reasamblați instrumentul
Reasamblați instrumentul
2898 - 307 - Replace front cover; Remark:2897
304 - Caution : Ensure all wiring is inside the instrument while replacing cover.
Ensure all wiring is inside the instrument while replacing cover.
307 - Replace front cover
Replace front cover
310 - 309 - Strângeți cele patru (4) șuruburi ale capacului; Remark:417
569—Atenție : Nu strângeți excesiv șuruburile.
Nu strângeți excesiv șuruburile.
309 - Strângeți cele patru (4) șuruburi ale capacului
Strângeți cele patru (4) șuruburi ale capacului
320 - 319 - Efectuați testul funcțional; Remark:347
319 - Efectuați testul funcțional
Efectuați testul funcțional
347 - Efectuați Testul funcțional pentru PRM-470, DET-HHD-RAP-RM01. ...
Efectuați Testul funcțional pentru PRM-470, DET-HHD-RAP-RM01.
322 - 321 - Documentați acțiunile de întreținere; Remark:
321 - Documentați acțiunile de întreținere
Documentați acțiunile de întreținere
2869 - 2585 - Documentați acțiunile de întreținere întreprinse; Remark:2866
2585 - Documentați acțiunile de întreținere întreprinse
Documentați acțiunile de întreținere întreprinse
2866 - Notați observațiile și rezultatele pentru Raportul de întreținere corect...
Notați observațiile și rezultatele pentru Raportul de întreținere corectivă.
4706 - 4705 - Submit report; Remark:4864
4705 - Submit report
Submit report
4864 - As specified by management or contractual obligations.
As specified by management or contractual obligations.