Manual 2100-670I
Page
28 of 47
Economizer
Economizer Components
Actuator
The actuator rotates up to 90° based on a 0-10v signal
sent to it by the controller. The actuator is rated at
44 lb-in and is spring return when power is lost. This
component is what opens and closes the damper blade.
To verify the output from the controller to the actuator:
1. Press MENU key to go to the Main Menu screen.
2. Press UP or DOWN keys and ENTER key to enter
TECHNICIAN password 1313.
3. Press UP or DOWN keys to scroll to
I/O Config
;
press ENTER key.
4. Press UP or DOWN keys to scroll to
Damper
Override (C14)
; press ENTER key.
5. Reference the
Damper Position
for the current
output to the damper (see Figure 44).
6. To override the current position, press ENTER key
to scroll to
Damper OV Pos
.
7. Press UP or DOWN keys to change the value to the
desired output.
8. Press ENTER key to save the value and move
cursor to
Override
.
9. Press UP or DOWN keys to change the value from
Disabled
to
Enabled
.
10. The
Damper Position
will update with the new
override value and the damper will travel to that
position.
NOTE:
This override will last for 5 minutes or until the
Override
is changed back to
Disabled
.
compressors at the same time when there is a quick
change in the load. When connected to the LV, this is
taken care of by LV logic.
Additional Compressor Alarms
Refrigerant Low Pressure Alarm
When the suction pressure transducer indicates
a pressure value less than the low pressure alarm
setpoint of 40 PSIG and there is an active call for
cooling, the controller will disable the compressor (after
a 180-second delay).
NOTE:
The second call will be
delayed based on the delay off value mentioned in the
compressor section.
The controller will try to run the
refrigeration system two (2) times within 900 seconds
before the alarm will lock the compressor out. This
alarm needs to be manually cleared before compressor
operation will resume.
To adjust the low pressure alarm settings:
1. Press MENU key to go to the Main Menu screen.
2. Press UP or DOWN keys and ENTER key to enter
USER password 2000.
3. Press UP or DOWN keys to scroll to
System Config
;
press ENTER key.
4. Press UP or DOWN keys to scroll to
Alarm Setup
(A6)
; press ENTER key.
5. Press ENTER key to scroll to
Delay
to adjust how
long the compressor waits before turning the
compressor off (see Figure 43).
6. Press UP or DOWN keys to adjust the time delay.
7. Press ENTER key to scroll to
Two Count Del
.
8. Press UP or DOWN keys to adjust the delay value.
9. Press ENTER key to save.
10. Press the ESCAPE key several times to return to
Main Menu screen.
FIGURE 43
Adjusting Low Pressure Alarm Settings
Dust Sensor
The unit has a dust sensor installed near the outdoor
air inlet. The dust sensor checks for excessive
particulates in the outdoor air, and will close the
economizer if the dust is excessive. The sensor uses a
PWM signal converted to 0-5v output to the controller.
FIGURE 44
Damper Override
