Programming The CUB Using the E2 or Einstein Front Panel
The MultiFlex CUB E2/ Einstein Interface • 29
The Combination Method determines how
multiple case temperature sensors in the case cir-
cuit will be combined into a single control tem-
perature value for use in comparing to the
temperature setpoint. There are five strategies to
choose from:
•
AVG
- The average value of all case temperature in-
puts.
•
MIN
- The lowest sensor value of all the case tem-
perature inputs.
•
MAX
- The highest sensor value of all the case tem-
perature inputs.
•
FIRST
- The lowest numbered temperature sensor
that is reading a valid temperature.
•
MIX
- A mixture of the first two valid case temp
sensor values. The percentage at which these two
sensor values are mixed is determined by the
Mix%
field.
Case Temp Mix
Visible only when the Comb Method is set to
MIX
, the
Case Temp Mix
field is the percent-
age used to mix the values of Case Temp 1 and
Case Temp 2. To mix the values, the CUB adds
x
% of Case Temp 1 to (100-
x
)% of Case Temp 2.
Temp Setpt
The temperature setpoint is the circuit tem-
perature to which the CUB will attempt to con-
trol the cases. Along with the temperature
deadband, the CUB uses this setpoint to deter-
mine when refrigeration is needed. Refer to
Sec-
tion 6.1.2., Case Temperature Compressor
Control
, for more on how the temperature set-
point works.
Temp Deadband
The temperature deadband is a range of tem-
peratures equally above and below the setpoint
within which the case circuit temperature is con-
sidered to be acceptable. While within this
range, the compressor will remain in its current
state until the temperature input value triggers a
change by moving above or below the deadband
range. Refer to
Section 6.1.2., Case Temperature
Compressor Control
, for more on how the tem-
perature setpoint works.
Min ON time
The Minimum ON Time is the amount of
time the compressor must remain ON after acti-
vation before being allowed to turn OFF. Enter
the desired minimum ON time in hours:min-
utes:seconds (H:MM:SS) format.
Min OFF time
The Minimum OFF Time is the amount of
time the compressor must remain OFF after
deactivation before being allowed to turn ON.
Enter the desired minimum OFF time in
hours:minutes:seconds (H:MM:SS) format.
Idle Pump Down
The
Idle Pump Down
field appears only if
using the temperature compressor control strat-
egy.
The
Idle Pump Down
field enables or dis-
ables the pump down delay that occurs in
between refrigeration and idle (off). If set to
ENABLE
, the CUB will turn the refrigeration
solenoid output OFF and leave the compressor
ON until the suction pressure is below the Mini-
mum Suction Pressure setpoint, or when Maxi-
mum Pump Down time expires. This effectively
pumps refrigerant out of the coil.
If set to
DISABLE
, the CUB will transition
from refrigeration to idle with no pump down
cycle.
Max pumpdown
The Max Pump Down time is the maximum
amount of time a Pump Down delay period will
last if it is not terminated prematurely by the
suction pressure falling below the Minimum
Suction Pressure value.
Ref/Comp ON Delay
This field appears only if using the tempera-
ture compressor control strategy and only if Idle
Pump Down is set to
ENABLE
.
The Ref/Compressor ON Delay affects how
long the CUB will wait after opening the refrig-
eration solenoid at the start of refrigeration
before activating the compressor. Enter the
desired delay in hours:minutes:seconds
(H:MM:SS) format.
