Ludlum Measurements 177, Руководство пользователя

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Model 177
Technical Manual
Section 2
Ludlum Measurements, Inc. Page 2-2 October 2018
Select the operating voltage. This voltage is set by the manufacturer for the
detector shipped with the instrument and recorded on the Certificate of
Calibration. For other detector/instrument setups, consult the detector manual
or manufacturer. Then adjust the
HV
potentiometer accordingly.
Note:
Most GM detectors will operate at 900 volts. However, some
smaller GM tubes operate at lower voltages.
Operating the Instrument
Connect a detector to the instrument. Obtain a meter reading from a check
source or calibrated source, if available. Remove the source.
Set the instrument to the appropriate range with the
RANGE
selector switch.
If the alarm point is not already set, press the
ALARM TEST
switch and adjust
ALARM SET
for the desired alarm point.
Note:
The meter displays the alarm set point when the
ALARM TEST
switch is depressed. Recheck the set point after locking the
ALARM SET
control.
Increase the meter count to exceed the alarm threshold. Both the alarm lamp
and audible alarm signal should activate.
Depress the
RESET
button. The meter needle should drive to zero and the
alarm circuit should de-energize, shutting off both the visual and audible
alarms.
Depress the
HV TEST
button and ensure that the high voltage is properly set.
Proceed with use.