PCM-2 Manual.pdf - Voss Associates

Electrical Power ~nsta~
Each of the sixteen detector chambers is connected to two gas plumbing
harnesses/manifolds; A red gas supply harness and a blue gas exhaust harness.
For faster purging, the supply hose should always connect to the lower-most gas
fittings of vertically mounted detectors.
If the Hand Probe Option (Option 1) is installed, a third gas flow meter and a
separate rate adjustment needle valve is provided. This single hand-held detector
will operate adequately on 5-10 cc/minute of PIO counting gas regardless of
whether or not a gas manager is present.
For units equipped with Spare Purging Detectors (Option 15), no special gas flow
rate adjustment considerations need be taken as these spare detectors are provided
with exhaust gas downstream of the main detectors.
For units equipped '';I'ith a Gas Manager (Option 12), refer to the Options Section
for detailed system adjustment direction as operation of the gas supply/exhaust
system is signifiacntly different from that of a standard unit.
Power is brought into the PCM-2 via a four-outlet power strip. Into this are
plugged power cords from the unit's lower electronics enclosure and options such
as a printer or badge reader. The line cord attached to this power strip may exit
the unit either through the lower rear corner of the cabinet or through the top of
the unit near its right-hand side, per user request. The default configuration for
power cord egress is through the lower rear power inlet plate.
While the PCM-2 is relatively immune to line noise and transients, it is possible
for very large power line spikes to interfere with the instrument. Avoid
connecting the PCM-2 to power circuits shared VJith large motors or other
inductive loads. If clean line power is not available, a line conditioner should be
installed.
To prevent unauthorized operation, the unit's on/off switch is placed on the right
side of the electronics enclosure internal to the unit behind the side door. This is
also the location of the fuse holder. If the fuse must be replaced, use a 3-Amp
1.25 x 0.25 inch slow blow fuse rated for 250 Volts.
Two operating voltage ranges are supported; 90-132 and 180-264 volts. This
selection is made by moving a recessed slide switch on the main computer power
supply inside the lower electronics enclosure. An inspection mirror may be used
to verify the position of this switch, which is located between the two outlets on
the right side of the power supply.
PCM2.MANI REV AI April 1995 2-3