Liebert Universal Monitor - Manual (Page 29)

Wiring and Connections - Main Board
21
4.2 Connecting Digital Inputs and Digital Outputs
The digital inputs and digital outputs are found on the lower right side of the Universal Monitor’s
printed wiring assembly board. There are two terminal blocks for the inputs—one green, the other
black. There are two terminal blocks for the outputs—one green, the other black.
To determine the proper wire size, see Table 7 - Wiring specifications - main board.
4.2.1 Connecting Digital Inputs
To connect an input:
1. Turn OFF electrical power to the Universal
Monitor.
2. If necessary, remove a conduit knockout to
permit wire entry into the Universal
Monitor enclosure.
3. Bring the wire(s) into the Universal Monitor
enclosure through a conduit knockout or
access slot.
4. Loosen the appropriate screw and slip the
stripped end of the wire into the terminal
block.
5. Tighten the screw until it holds the wire
snugly.
4.2.2 Connecting Digital Outputs
To connect an output:
1. Turn OFF electrical power to the Universal
Monitor.
2. If necessary, remove a conduit knockout to
permit wire entry into the Universal
Monitor enclosure.
3. Bring the wire(s) into the Universal Monitor enclosure through a conduit knockout or access slot.
4. Loosen the appropriate screw and slip the stripped end of the wire into the terminal block.
5. Tighten the screw until it holds the wire snugly.
NOTE
Each terminal block is a removable, two-part assembly to permit easier connection of more
than one input at a time. If making multiple connections, grasp the upper portion of a block
and pull firmly to the right until the assembly pulls apart.
After making the connections, push the removed piece back into the portion attached to the
printed wiring assembly until the terminal block pieces lock together.
!
CAUTION
To reduce the risk of fire or electric shock, do not interconnect the outputs of
different Class 2 circuits.
TB2:
CONTACT
INPUTS
TB3:
RELAY
OUTPUTS
ASS
REV
ON
PFM5
OFF
ON
PFM2
OFF
(BOTTOM)
(TOP)
4
3
2
1
8
7
6
5
(BOTTOM)
(TOP)
4
3
2
1
8
7
6
5
OUTPUT TERMINAL BLOCKS -
Note numbering of outputs
begins at the bottom and
proceeds up; numbering
keys are shown at right
INPUT TERMINAL BLOCKS -
Note numbering of inputs
begins at the bottom and
proceeds up; numbering
keys are shown at right
Numbering keys