Endress+Hauser gammapilot FTG 671, Руководство по эксплуатации

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Trouble-shooting table Use the following Table to check for faulty operation
7.2 Fault by Gammagraphy
Gammagraphy is a destruction-free material test for piping, pressurised tanks, etc. and
uses radioactive gamma sources. The high sensitivity of scintillation detectors to gamma
radiation may mean that spurious radiation due to gammagraphy will cause the evalua-
tion device to show the wrong display which suggests that the level is lower than it really
is.
If the gammagraphy detection function is required, it is necessary to use the FMG 671
instead of the FTG 671. For more detailed information, please consult the Operating
Instructions FMG 671, BA 133F/00/en.
Fault Cause and remedy
Dose rate for unhindered radiation
too low
•
Radiation switched off
- switch on again
•
No radionuclide in source container
-
load source capsule in container
•
Detector incorrectly orientated with respect to detector
- turn detector
•
Detector mounted end-on (DG 17, DG 27)
- mount horizontally
•
Gamma beam not precisely aligned
- re-align
•
Fittings in vessel not considered in activity calculation
- recalculate activity and change source accordingly
•
Build up in vessel
- Clean vessel
•
Source too weak
- employ source with higher activity
Dose rate for unhindered radiation
too high
•
Detector has two counter tubes (DG 27)
- Use detector with one tube only
•
External radiation
-
Shield off if possible
•
Activity too high
- Exchange radionuclide or attenuate radiation,
e.g. by mounting a steel plate in front of source
container.
Dose rate for covered barrier too
high
•
External radiation source in use (gamma radiology)
- Shield off if possible
Relays do not trip correctly
•
Wrong fail-safe mode selected
- re-enter switch points
•
Incorrect integration time settings
- Increase time or hysteresis if relays »flutter«
- Decrease time if delay too long
•
Wiring or load incorrect, see »Installation«
- Use simulation mode to check correct switching
Alarm relay lights or blinks
•
See Table 6.1
No communication with ZA 67
… •
Check address switch
•
Check wiring
Table 7.2
Trouble shooting table for
incorrect function without error
message
Gammapilot FTG 671 Chapter 7: Trouble-Shooting
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