PCM-2 Manual.pdf - Voss Associates

CAUTION:
DO NOT use compressed shop air as in-line lubricants will contaminate internal
probe chamber surfaces.
At this point in the assembly the probe chamber is clean to the degree necessalY to ensure
acceptable electronic perfonnance when complete.
NOTE:
All subsequent assembly operations should ideally be performed using lint-free
cloth or power-free latex gloves to preserve the overall cleanliness of the probe's
internal surfaces. If gloves are not worn, EXTREME CARE MUST BE
EXERCISED to avoid touching the probe's inner surfaces. PART
CLEANLINESS MUST BE PRESERVED THROUGHOUT THE REMAINDER
OF THE PROBE'S ASSEMBLY.
Build the main turret subassembly by installing the brass turret spindle onto the turret cap
and then pushing the cap shaft into the corresponding large, unchamfered hole in the turret
post. This is an interference fit and may require significant axial force. Avoid bending the
cap shaft by applying only direct axial force. The spindle should be sandwiched tightly
between the post and cap when completed. If the turret cap tends to "rebound" (i. e. a
tightly sandwiched fit of the brass spindle between the post and cap can not be achieved)
remove the entire turrct assembly, discard the teflon cap & post and replace with new cap &
post components reusing the brass spindle. Likewise, if the cap shaft does not fit snugly into
the turret post when assembled (i.e. if it can spin, or exhibits very minimal resistance when
assembled into the turret post), discard the teflon cap & post components, again salvaging the
brass spindle & reassemble with new parts. Do not separate this subassembly once it
is built.
All main turrets can be installed in the detector as subassemblies by pushing them straight
down onto their protruding #2-56 press studs in the detector pan. Avoid bending the cap shaft
by applying only direct axial force. At this point again note if the turret cap tends to
"rebound" when installed as in step 5 above. Do not separate these main turret
subassemblies once they are built. The wire end turrets which are installed at each wire end
position of each detector channel require different assembly considerations.
Install the wire end turrets (6 places per long probe and 2 places per medium &: small probes,
reference drawings) by first pushing the turret post components straight down onto the
protruding #2-56 press studs in the detector pan. noting: that the end of the post with the
chamfered hole goes down against the detector pan. Next, complete the wire end turret
subassembly exactly like the main turret subassembly except substitute the formed anode wire
spring in place of the brass turret spindle. Note that the properly built wire end turret
subassembly will not allow the anode wire spring to be tightly sandwiched between the teflon
cap and post and it can therefore spin freely about the cap shaft. Observe the same assembly
considerations and cautions as in steps 5 & 6 above. Again, do not separate these wire end
11000-A308/PCM-2 Del. Assy. Procedure/Revision/March 1994