Powering Up; Zeroing The Unit; Prior To Operation - ThermoFisher Scientific GLD PRO Manuel D'utilisation

3.0 Powering up

Depress and hold the power button (Figure 1) until the unit responds with the wake-up
mode. The leak detector will run through a self calibration sequence for approximately
15 seconds. During this time DO NOT attempt to zero the unit.

4.0 Zeroing the unit

After the LED lights stop flashing, the unit is ready for use. The instrument may need
to be zeroed periodically between uses, especially if it is moved from room to room or
between areas of differing temperature or humidity. Do not attempt to zero the unit while
the probe is stored in the holder. The probe MUST be removed from the probe docking
station before zeroing the unit. To re-zero, press the zero set button. The unit will run a
self-calibration sequence for approximately 4 seconds. When all LED lights stop flashing
and the blue LED light is lit, the unit is ready for use.
NOTE: To avoid false readings, do not attempt to use or zero the unit while the self-
calibration sequence is in progress.
Figure 1 – Leak detector schematic

5.0 Prior to operation

Verify the operation of the leak detector before each use by sampling gas from a GC split
vent or other source of hydrogen or helium. Also, visually inspect the probe tip, reference
gas inlet, and exhaust port for obstructions (Figure 1).
IMPORTANT: Fittings being checked must be clean and dry; liquid leak detecting
agents, dust, and other debris may damage the leak detector if drawn into the probe.
The leak detector responds to almost any gas you can smell and many gases that you
can't smell. Solvent vapors, split vent exhaust, or even strong air currents around the
probe or reference inlet can cause instability or false positive readings. Be careful not to
breathe into the reference inlet when checking for leaks or to cover/block the inlet with
your hand.
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