7 | EP Series
970-293 (2014/06)
CA Series
Subject to change without prior notice
Console Model
Low Pressure Protection | 7
user can select either two or four times by changing
switch four (4) on the DIP switch SW1 (shown on table
3) on the UPM board.
LOW PRESSURE PROTECTION
If the LPC switch is open upon a Y call the UPM will not
energize the CC output and therefore the compressor
will remain off, the fault LED will flash two (2) times for
the LPC and the alarm contact will remain off.
If the compressor is running in normal mode on a Y call
and the low pressure switch opens, the UPM will keep
the compressor running for two (2) minutes if the
condition remains after this period of time the
compressor will shut down and the UPM will start a soft
lockout. The UPM will flash two (2) times for the LPC.
And the alarm contact will remain off.
If the switch closes, the UPM will start the compressor
after the anti short cycle has expired UPM will energize
the compressor output.
Caution
IMPORTANT: To exit the hard lockout the
controller must be reset from the Y or R
terminal by removing the power from the
selected terminal. The user can choose which
will be the reset point via the DIP switch SW1.
GROUND
The UPM controller takes its ground reference from the
unit chassis which is connected to the controller via the
C- GND spade terminal.
DIP SWITCH SETTINGS
The DIP switch is used to configure most of the available
features of the UPM as follows:
•
Alarm mode, Constant or Pulse
•
Reset mode, Y signal or R signal
•
Lockout mode, two (2) or four (4) Strikes
• Test mode, Normal or Test operation
The settings shown below are factory default for most
heat pump applications, however the Unit wiring diagram
is the ultimate guide for factory DIP switch default
settings (Figure 2).
1 2 3
4
ON
Lockout
Reset
Alarm
Test
Figure 2
The following table is available on the UPM board as well
and it depicts the switch position and its associated
functionality.
UPM Dip Switch Configuration
4
LOCKOUT
4
2
3
RESET
R
Y
2
ALARM
CONT
PULSE
1
TEST
YES
NO
Figure 3
SELECTABLE ALARM MODE
The UPM controller can be configured to have either a
constant signal or a pulse.
If constant (CONT) is selected the UPM will provide a
closed contact until the alarm is cleared.
If pulsed (PULSE) is selected the UPM will sequence the
alarm contact with the fault LED flashes.
FREEZE PROTECTION
The default setting for the freeze limit trip is 30°F,
however this can be changed to 15°F by cutting the R42
resistor located on top of the DIP switch SW1.
The UPM controller will constantly monitor the refrigerant
temperature with the sensor mounted close to the
condensing water coil between the thermal expansion
valve and water coil as shown in figure 4. If temperature
drops below or remains at the freeze limit trip for 30
seconds, the controller will shut the compressor down
and enter into a soft lockout condition. Both the status
LED and the Alarm contact will be active. The LED will
flash (three (3) times) the code associated with this alarm
condition.
Freeze
Protection
Sensor
Figure 4 Freeze Protection Sensor
