12 • MultiFlex CUB-II and CUB-TD I&O Guide
026-1705 Rev 7 06-APR-2010
4.2.1. Relay Output Ratings and Fuse
Protection
Each relay output on the MultiFlex Combi-
nation I/O boards is rated for up to 240 VAC
with a maximum current of 2 amps.
Each relay is fused with a 2 amp fast-blow
5mm x 20mm fuse, Bussman GMA-2 or equiva-
lent.
4.2.2. Wiring Outputs to Points
The MultiFlex CUB has Form C relay con-
tacts.
Figure 4-4
shows how to wire the three-
terminal Form C contact.
One wire of the two-wire connection should
always be connected to the middle terminal. The
second wire must either be connected to the N.C.
terminal (if you want the path to be closed when
the relay is de-energized) or the N.O. terminal (if
you want the path to be open during power fail-
ure).
4.2.3. MultiFlex CUB Fixed Outputs
The MultiFlex CUB supports a large number
of different types of output devices that might be
found on a single condensing unit’s pressure
control, condenser control, or refrigeration con-
trol systems. Because output locations are speci-
fied by the user in the system software, you can
connect outputs from the condensing unit to any
point on the CUB. However, to make setup eas-
ier, the CUB has assigned default sensor loca-
tions to a few of the inputs on the board.
Table 4-1
lists the inputs with assigned
defaults. If you choose to not use the defaults
listed, you may change any or all of them in the
system software (see
Section 7.3.7., Screen 7:
Outputs
and
Section 8.2.8., Outputs Screens
).
Figure 4-4 - Form C Contact Wiring
N.C. N.O.
N.C. N.O.
RELAY IS
CLOSED
ON POWER
FAILURE
RELAY IS
OPEN ON
POWER
FAILURE
CUB
Output
Point
Number
Label
Device to Connect
To This Point
1
Compres-
sor
Compressor
2
Defrost
Electric defrost heaters
or hot gas valve
3
Condenser
Fan #1
Condenser fan (or 1st
condenser fan if multi-
ple fans are present)
8
Alarm Out-
put
Digital contact closure
that is ON when an
alarm condition is
active in the condens-
ing unit.
Table 4-3 - CUB Default Outputs
