RFS APD-D Series Product Manual page 11

If the system pressure rises to the high
pressure alarm threshold, then the HIGH
PRESSURE front panel indicator will be lit
and the NC/COM/NO alarm connector
pins (pins 4, 5 and 6) will switch states.
The compressor will be disabled to avoid
any further pressure increase. This alarm
is non-latching and will clear if the
pressure drops
threshold.
4.4.2 Humidity Alarm: Elevated humidity can
cause condensation, which could affect
system performance.
humidity alarm can be used as a warning
that the dryness of the air in the
waveguide or cable may not be sufficient
to avoid condensation
temperature drops.
If the distribution system air relative
humidity rises above the humidity alarm
threshold, then the HUMIDITY front panel
indicator will be lit and the NC/COM/NO
alarm connector pins (pins 7, 8 and 9)
will switch states. This alarm is non-
latching and will clear if the humidity
drops below the alarm threshold.
Since the alarm occurs well below the
point where condensation would occur,
isolated short duration RH alarms are
typically used as a warning. Increasing
alarm occurrences over a period of time
or a constant RH alarm for 24 hours or
more indicates that the dehydrator
should be checked for proper operation.
Based on unit duty cycle, operational
environment and age, more frequent RH
alarms may indicate the need to replace
the desiccant cylinders.
The humidity sensor requires air flow for
accurate measurement. In order to
accurately measure
humidity level, humidity monitoring is
only active during pumping and purging
cycles. For this reason, the system purge
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below the alarm
The optional
if the air
the system air
option is required when the humidity
alarm option is present.
4.4.3 Run Time Alarm: The optional run time
alarm can be used as a warning that the
active operation
dehydrator is too long. The occurrence of
this alarm typically indicates a leak in the
distribution system.
The run time alarm must be configured
based on a calculation or measurement of
how long the unit will take to fill the
system volume during active operation. If
the active operation time to pressurize
the distribution system to the upper
operational
configured run time, then the RUN TIME
and COMPRESSOR indicators will flash
once per second and the NC/COM/NO
alarm connector pins (pins 10, 11 and 12)
will switch states. This alarm is non-
latching and will clear when the unit is
able to pressurize the system to the upper
operational pressure.
NOTE: Active
exceeding the
Active Operation
damage the unit and will void the unit's
warranty.
4.4.4 System Purge: The system purge option
allows the
periodically be purged (drained) and
refilled with pressurized dry air. At the
configured set time, the system purge
valve will be opened and the distribution
system air will be released until the
dehydrator's lower operational pressure
is reached.
602400011500
Revision C
duration of
pressure exceeds
operation durations
Maximum Continuous
specification
distribution system
the
the
may
to