8
Pub. No. OM-A-75 REV. 4 — March 2006
LEDs on the DDG unit indicate which temperature is being
displayed. Pushing the SELECT key will cycle between
Fahrenheit and Celsius temperature scales. The LED
labeled “OPTIONAL” corresponds to the dew point
temperature. If your unit does not include this option, the
temperature displayed when the “OPTIONAL” LED is lit
will be about 30° by default. This does NOT indicate that
the dew point is actually 30°.
Drain Operation
Locking/Unlocking Drain Time Settings:
The ON
TIME and OFF TIME settings for all modes of drain
operation can be unlocked or locked to avoid inadvertent
changes to these settings. In the unlocked condition, the
time settings will flash after the SELECT key is pressed
momentarily, indicating that the values can be changed by
pressing the UP (
↑
)or DOWN (
↓
) arrow keys. In the
locked condition, the SELECT key must be held down for 5
seconds before the display will flash and the settings can
be changed. With the display flashing, pushing the
SELECT key momentarily will return to normal unlocked
operation and holding the SELECT key down for 5
seconds will return to normal locked operation.
Setting Drain ON TIME and OFF TIME:
1.
Press the UP (
↑
) or DOWN (
↓
) arrow keys until the
LED indicates that ON TIME or OFF TIME has been
selected.
2.
Press SELECT momentarily (if unlocked) or hold until
the display starts flashing (if locked). If you do not
know whether the setting is locked or not, simply
press the select button momentarily. If the digits on
the LCD display do not start flashing, the setting is
locked.
3.
Press UP (
↑
) or DOWN (
↓
) arrow keys to change the
settings. The ON TIME is indicated in seconds and
changes in 0.5-second increments in a range of 0 to
60 seconds. The OFF TIME is indicated in minutes
and changes in 0.5-minute increments in a range of
0 to 60 minutes.
Modes of Drain Operation:
The DDG Controller has
two modes of drain operation for different drain types. The
mode of operation for timed drains (i.e. 4477 A, B, or C
models) is described below as item “A.” The mode of
operation for fully automatic float operated drains (i.e.
model 4488) is described as item “B.” For all modes, the
“DRAINS POWER ON” LED indicates that the drain is
receiving power. Pushing the DRAIN TEST key will send
power to the drain if it is not already receiving power.
A.
Timed Drain Mode (model 4477 A, B, or C drains):
Set ON TIME and OFF TIME to non-zero values.
Settings should be such that fluid is adequately
drained without allowing excessive air loss.
B.
Demand Drain Mode (model 4488 drains):
Set ON TIME and OFF TIME to zero. Drain is given
continuous power supply and will operate normally.
In this mode, pushing the DRAIN TEST button will
have no effect.
Alarm Indication
The following conditions can cause the alarm indicator to
light:
• Compressor overload
• Low refrigerant suction pressure
• High refrigerant discharge pressure
• Low oil pressure (semi-hermetic compressors only)
A qualified refrigeration mechanic should identify and
correct the problem if an alarm condition occurs.
In most
cases it will be necessary to firmly depress the
reset push-button located on the dual-pressure
switch, which is inside the electrical enclosure.
Follow all safety procedures applicable to electrical
equipment when opening the electrical enclosure. Refer to
the Installation, Operation, Start-Up, and Maintenance
Manual for more information.
Service Due Indication
“Service Due” indicates the dryer is due for routine
maintenance. Please read the maintenance section or
contact your Pneumatech dealer. In SERVICE DUE mode,
several functions relating to the accumulated run time can
be accessed. The accumulated run time can be viewed,
and the service due threshold (total accumulated run time
before SERVICE DUE indicator lights) can be viewed and
tested.
Drains will not operate normally in Service
Due mode. Drains will not receive power
in Service Due mode unless the DRAIN
TEST key is held down. Never operate the
unit in Service Due mode for an extended
period of time.
