28 • MultiFlex CUB-II and CUB-TD I&O Guide
026-1705 Rev 7 06-APR-2010
Wash Switch
The
Wash Switch
field specifies whether
this condensing unit has a clean switch to toggle
the case circuit in and out of Wash mode. If a
clean switch input is available, set this field to
ENABLE
.
Eng Units
Engineering Units determines whether engi-
neering units for pressure values will be dis-
played using English units (pounds per square
inch (PSI) ) or metric units (kilopascals (KPA) ).
Temp units
Temperature Units determines whether engi-
neering units for temperature will be displayed
in degrees Fahrenheit or degrees Celsius.
Zone Assoc.
Zone Association allows you to assign this
CUB to a zone along with other CUBs in the
same motor room. This will cause the motor
room temperature to be displayed on the CUB-
II’s status screen in E2 or Einstein, and it also
affects which of the “SPARE ANALOG OUT”
Global Data inputs a motor room temperature
sensor sends its value to (see
Section 6.4.2.,
Motor Room Temperature Control
, for an expla-
nation of how this works).
Byp Failsafe Tm
Bypass failsafe time is the maximum amount
of time the CUB will stay in Bypass mode (Ref
Override On). This and any other bypass modes
can be cancelled by issuing an End Manual
mode.
Network Alm
This field specifies whether you want the
CUB to set its alarm output if it goes offline.
Network Time
This field specifies whether you want the
CUB to keep its own time clock synchronized
with its parent controller’s clock. Set this field to
ENABLE
if you want CUB to synchronize its
time with E2 or Einstein, or
DISABLE
if you
don’t want time synchronization.
7.3.2. Screen 2: Setpoints
The Setpoints screen is where all setpoints
related to compressor and condenser fan control
are entered. The fields that appear on this screen
depend largely on whether you set the Control
Strategy in Screen 1 (
Section 7.3.1.
) to
Pressure
or
Temperature
and whether you set the Con-
denser Strategy to
Pressure
or
TD
. The field
descriptions below will indicate whether each
field is visible for only the Pressure strategy, for
only the Temperature strategy, or for both.
Cut In and Cut Out
If you are using the Pressure compressor
control strategy, the Cut In setpoint determines
the suction pressure that, when exceeded, will
cause the compressor to turn ON. In this strat-
egy, the compressor will remain ON until the
pressure falls below the Cut Out setpoint, at
which point the compressor will turn OFF.
If you are using the temperature compressor
control strategy, these setpoints are used as a fall
back if the MultiFlex CUB cannot determine the
current case temperature. When this occurs, the
suction pressure becomes the control input, and
the CUB uses the Cut In and Cut Out setpoints to
control the compressor.
Comb. method
The
Comb. method
field appears only for
the temperature compressor control strategy.
Figure 7-4 - Screen 2: Setpoints Screen
