Greenheck Microprocessor Controller (475595 IOM) TAP v2.10 April 2014 (RVE, ERCH-01, ERT-01) User Manual
Page 30
T
HIS
SCREEN
DISPLAYS
THE
DIGITAL
SCROLL
COMPRESSOR
PARAMETERS
.
This screen only appears if a digital scroll compressor was provided with the unit.
Minimum OFF: This is the minimum voltage the controller outputs when the
digital scroll is disabled/OFF
Minimum ON: This is the minimum voltage the controller outputs when the digital
scroll is enabled/ON.
Maximum: This is the maximum voltage the controller outputs when the digital
scroll is operating at full capacity.
Delay OFF: Delays shutting off digital scroll by this duration.
Max Power Start: Upon starting, the digital scroll will run at full capacity for this
duration. This ensures the refrigeration system is at proper conditions, prior to
modulation.
Digital Compressor
Minimum OFF:
1.0vdc
Minimum ON:
1.9vdc
Maximum: 5.0vdc
Delay OFF:
60s
Max Power Start:
120s
T
HIS
SCREEN
DISPLAYS
THE
NUMBER
OF
STANDARD
COMPRESSOR
STAGES
PROVIDED
WITH
THE
UNIT
AND
SHOWS
THE
ROTATION
SEQUENCE
.
This screen only appears if DX cooling was provided with the unit.
The number of stages displayed is equal to the number of non-modulating
compressors. Factory default compressor rotation is LIFO (Last In, First Out).
Compressor rotation can not be changed on units equipped with: Digital Scrolls,
Hot Gas Reheat or Heat Pump.
Compressor Setup
# of stages:
2
Rotation: LIFO
T
HIS
SCREEN
ALLOWS
THE
ADJUSTMENT
OF
THE
COLD
COIL
FREEZE
-
UP
PROTECTION
PARAMETERS
.
This screen only appears if DX cooling was provided with the unit.
This sequence protects the evaporator coil from freezing up in cooling mode
when the discharge air sensor is registering false readings.
Temp Diff: The minimum supply air temperature setting (see page 15) minus the
temp diff setting represents the cold coil low temperature limit.
Lockout Delay: If the cold coil temperature drops below the low temperature limit
for the set lockout delay, the cooling loop will reference the cold coil temperature
in lieu of the discharge air sensor to prevent freeze ups.
Lockout Time: This is the amount of time the discharge air sensor will be locked
out during the cold coil protection sequence.
After three lockouts, the unit will go into alarm and the discharge air sensor will be
locked out until the alarm is cleared.
Cold Coil Protection
Temp Diff:
5.5°F
Lockout Delay:
10s
Lockout Time:
600s
T
HIS
SCREEN
ALLOWS
THE
ADJUSTMENT
OF
THE
DEFROST
CYCLE
TIMERS
.
This screen only appears if Timed Exhaust Frost Control or Energy Wheel Cycle
Frost Control was provided with the unit.
The ON/OFF times prevent the build up of frost on the energy wheel if frost
conditions are present.
Defrost Cycle Setup
Defrost minimum cycle
times.
Defrost mode:
5min
Normal mode:
30min
T
HIS
SCREEN
ALLOWS
ADJUSTMENT
OF
THE
C
OOLING
PI
CONTROL
LOOP
.
This screen only appears if cooling option was provided with the unit.
The controller utilizes a PI loop control for cooling. This allows for less sporadic
changes in supply temperature, resulting in a smooth reaction to changing
conditions. To speed up reaction time, decrease the integration time. For slower
reaction time, increase the integration time. When making adjustments, make
them in small increments and test the system to determine if the new setting is
adequate prior to further adjustment. The band is the range that the integration
will occur between.
Cooling Controller
Integration: 300s
Band: 20°F
30
DDC Controller for Tempered Air Products
®