Endress+Hauser gammapilot FTG 671, Operating Instructions Manual

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7.4 Exchanging transmitters and detectors
Transmitter If the Gammapilot FTG 671 has to be exchanged, the replacement need not be
recalibrated. Instead all the matrix values noted down at the time of the commissioning
(Table in back cover) can be used to quickly commission the new transmitter.
Step Matrix Entry Significance
1 V3H0 3 Select calibration on instrument exchange
2 - »E« Registers entry
3 V3H4 YWWD Enter the date of original calibration (see Section 4.1)*
4 - »E« Registers entry
5 V3H5 YWWD Enter today’s date
6 - »E« Registers entry
7 V3H6
…
Enter countrate/frequency of original free calibration
8 - »E« Registers entry
9 V3H7
…
Enter countrate/frequency of original covered calibration
10 - »E« Registers entry
11 V0H1
…
Enter normalised countrate of original free calibration
12 - »E« Registers entry
13 V0H2
…
Enter normalised countrate of original covered calibration
14 - »E« Registers entry
15 V0H9
…
If originally used, enter background radiation count
- otherwise confirm "0" with »E«
16 - »E« Registers entry
17 V0H4
…
Enter integration time and
V1H0
…
V1H9 relay parameters
*For Co-60 source and DG 17/27 detector, make additional entries at V3H1 (=1), V3H2 (=1/2)
On completion of the above procedure, the barrier now functions as before. If you did
not note your parameters, a recalibration is necessary.
If your parameters have been downloaded from a computer, you need only enter the new
date at V3H5; all other values are registered by pressing »E«.
Re-commissioning the
transmitter If the transmitter is switched off for some time, then the above procedure need not be
run through on re-commissioning: after calling the re-calibration procedure with
V3H0 = 3, only today’s date at V3H5 has to be re-entered. This ensures that the source
decay compensation values are brought up to date. This is particularly recommended
for the Co 60 source which changes at ca. 1% per month. In comparison, Cs 137 changes
at the rate of 0.2% per month.
Detectors If the detector is exchanged or moved, a completely new calibration as per Chapter 4,
Section 4.2, 4.3 or 4.4 is necessary.
Source If the source is exchanged or the source container moved, a completely new calibration
as per Chapter 4, Section 4.2, 4.3 or 4.4 is necessary.
Gammapilot FTG 671 Chapter 7: Trouble-Shooting
53