Pneumatech EH Series, Руководство пользователя

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OPTIONS LISTING WITH EXPLANATION
(PH/EH only)
AUDIBLE ALARM
The Audible Alarm consists of a buzzer with reset push
button and ON/OFF selector switch.
The audible alarm provides an audible warning to alert
an operator that the dryer is not functioning properly.
This option is used with options such as “Failure to Shift
Alarm” or “High Humidity Alarm.”
FAILURE TO SHIFT ALARM
The Failure to Shift Alarm consists of an alarm light that
illuminates if the desiccant towers fail to shift at a
prescribed time. Dry contacts are provided for remote
annunciation.
HIGH HUMIDITY ALARM
The High Humidity Alarm consists of an alarm light
controlled by a hygrometer that senses the dewpoint at
the outlet of the air dryer. This alarm illuminates when
the dewpoint reaches -20°F (-29°C) and above. A small
amount of sample air is required for operation. Dry
contacts are provided for remote annunciation.
Calibration:
To maintain accuracy, replace the probe
every two years.
Probe Replacement:
Turn the normal/demand selector
switch to the normal position. This will disable the
contacts for Dewpoint Demand. Isolate and depressurize
the probe chamber. Replace the probe. Pressurize the
probe chamber and turn the power back on.
MOISTURE INDICATOR
The moisture indicator consists of a small, clear,
polycarbonate filter filled with a color change silica gel. It
is located at the outlet of the dryer. When the dewpoint is
below -10°F (-23°C), the desiccant is deep orange.
When the dewpoint is above -10°F (-23°C), the
desiccant is translucent. A small amount of sample air is
required for operation.
FILTER HOUSING SILICA GEL
FIGURE 7 — MOISTURE INDICATOR
PANEL LIGHTS
The Panel Light option consists of four lights: Left Tower
Drying, Right Tower Drying, Left Tower Regenerating,
and Right Tower Regenerating. These lights are for
dryer sequence indication.
PLC CONTROLLER
PLC Controller can also be added to control the
operation of standard regenerative dryers. Typically
Square D or Allen Bradley PLCs are used.
DEWPOINT DEMAND CONTROL
“DPD”
The Dewpoint Demand control is an energy saver that
can extend the drying cycle
without purging , during
periods of lower moisture loads. The Dewpoint Demand
system offers, in one compact package, the utmost in
flexibility and accuracy sensing the actual dewpoint of
the outlet air. The hygrometer senses the dewpoint at
the outlet of the dryer at the end of the drying cycle, and
extends the drying cycle until the preset adjustable
dewpoint setpoint is reached. During this extended
drying cycle, the purge valves are closed and the
opposite tower is pressurized and prepared for the
drying cycle. The dewpoint demand option reduces
purge loss and extends valve life. This option consists of
the following:
• Digital Dewpoint Display
• Adjustable Setpoints
• Demand Cycle Light
• High Humidity Alarm Light with Dry Contact
• 4-20mA Output
Calibration:
To maintain accuracy, the probe should be
recalibrated annually. Recalibrated probes are available
through your local distributor.
Probe Replacement:
Isolate and depressurize the
probe chamber. Disconnect the sensor cable from the
sensor. Remove, and replace the probe. Pressurize the
probe chamber and connect the sensor cable. A small
amount of sample air (approximately 2-10 SCFH) should
expel out the chamber needle valve.
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