Thermo Scientific SGD-O, User Manual

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Thermo Fisher Scientific SGD-O User Guide
3-1
Chapter 3
Detector Setup & Pre-Calibration
For best performance, the detector must be adjusted for maximum signal
on empty pipe. To do this, the unit must be connected to the transmitter
and power applied.
Note
There must not be any other nuclear sources within 10 feet of the
unit being set up and calibrated.

1. If the radioactive source has a shutter assembly, verify that it is in the
ON position (shutter is open). If it is a high-pressure unit, the source
will not have a shutter, and you can skip this step.
2. Remove the lid of the detector housing. Set it aside, leaving the wiring
from the lid to the detector connected.
3. Verify that the J1 connector is running parallel with the pipe that the
gauge is mounted on. This will orient the reed switch for proper
operation. Also verify that the hold down bolt is tightened properly.
4. Refer to Figure 3–1. Use a voltmeter to verify that the +15 Vdc (pin 4
of J1) and -15 Vdc (pin 1 of J1) (power ground – pin 5 of J1) are there
and within ± 0.5 Vdc of specified voltage. If one or both of the voltages
are incorrect or not there at all, either the transmitter to detector cable
is bad or the transmitter is not outputting the ±15 Vdc properly.
Procedure