CommScope DryLine ODPMT200 Series, User Manual

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ODPMT200 Series DryLine® Dehydrator User Manual
8
Route the wires from the alarm control through
the liquid-tite fitting at bottom of unit into the
chassis and up to the terminal block
Tighten the screws on the terminal block, tie
wrap the alarm cable, and tighten the liquid-tite
fitting.
When a low pressure alarm condition exists dry
contacts are activated at terminal block TB-1.
An alarm condition exists when pressure falls
below 1.0 lb/in2 (6.9 kPa) for all ODPMT200
models. The relay contacts are rated at 2 A (non-
inductive), 30 Vdc.
Optional alarms (if purchased) will also be
located on this terminal block. The alarm
connection label, located inside of the front
cover, will provide terminal numbers for each
additional alarm.
2.7 Connecting Dehydrator to the Transmission
Line
Check the antenna and transmission
line system pressure rating before
connecting the dehydrator to the
system.
Insert one end of the 3/8” polytube feed line
tubing into the compression fitting on the
dehydrator inside wall, or one of the similar
fittings. Tighten securely with a 9/16” wrench.
Be careful not to over tighten. Connect the other
end of the polytube to the transmission line.
Two air outputs are provided, with individual
shut-off valves on the front of the unit. Make
sure that the valve is open position for each
transmission line connection. If one of the
outputs connection is not used, close the valve
and leave the port capped.
Note:
If the transmission lines have not been
purged, continue with section 2.8. Otherwise
proceed to Section 3.
2.8 Purging the Transmission Line
Air in the transmission line system must be
replaced with dry air to ensure satisfactory
opera-tion of the transmitted signal.
1. Determine the total system volume.
2. Divide the system volume by the flow rate
of the dehydrator (12 CFH) to determine the
number of hours needed for the purge cycle.
3. Open the far end of the transmission line.
4. Operate the dehydrator for one purge cycle.
If it is not possible to open the far end of the
transmission line:
1. Connect the dehydrator to the trans mission
line and pressurize the system.
2. Wait 45 minutes while the air absorbs
moisture in the system, then disconnect the
dehydrator from the transmission line and
allow the air to vent.
3. Repeat steps 1 and 2 three times to purge
the system.