Emerson Autochangeover Controllers AC8 - Manual (Page 23)

Wiring and Connections
15
3.2.2 Connecting Digital Outputs
To connect a digital output:
1. Turn OFF electrical power to the AC8.
2. If necessary, remove a conduit knockout to
permit wire entry into the AC8 enclosure.
3. Bring the wire(s) into the AC8 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.
3.2.3 Setting the Digital Output Jumpers
Each digital output has an associated jumper to define its operation when power is interrupted and
there is no battery backup to the board. This puts the AC8 in a fail-safe mode and ensures proper
functioning when the board has no power or battery backup.
The AC8 comes from the factory with all digital output jumpers in the OFF position (Normally Open).
The jumper setting for each digital output can be changed to ON (Normally Closed). The settings are
shown in Table 5.
To change the output jumper setting:
1. Find the respective black output jumper on
the circuit board, shown in the illustration,
using the following guide.
2. Decide whether your configuration requires
the jumper to be OFF or ON.
3. Set the jumper as needed:
• Set the jumper to OFF by placing the black jumper on the middle and top pins.
• Set the jumper to ON by placing the black jumper on the middle and bottom pins.
!
CAUTION
To reduce the risk of fire or electric
shock, do not interconnect the outputs
of different Class 2 circuits.
Table 5 Digital output jumper settings
Setting
Output status
(power loss & no battery backup)
OFF Normally Open
ON Normally Closed
Jumper Associated output
PFM1 Output 1
PFM2 Output 2
PFM3 Output 3
PFM4 Output 4
PFM5 Output 5
PFM6 Output 6
PFM7 Output 7
PFM8 Output 8
RELAY
OUTPUTS
TB2:
REV
ONON
PFM5
OFF
(BOTTOM)
(TOP)
4
3
2
1
8
7
6
5
(BOTTOM)
(TOP)
4
3
2
1
8
7
6
5
ON
PFM2
OFF
ON
PF
DIGITAL OUTPUT
TERMINAL BLOCKS
NUMBERING KEYS -
Note numbering begins
with 1 at the bottom and
proceeds up to 4 (green);
and 5 up to 8 (black)
RELAY
OUTPUTS
TB4:
(BOTTOM
2
REV
ONON
PFM5
OFF
(BOTTOM)
(TOP)
4
3
2
1
8
7
6
5
(BOTTOM)
(TOP)
4
3
2
8
7
6
5
ON
PFM2
OFF
NC
C
NO
NC
C
NO
ON
PFM3
OFF
ON
PFM8
OFF
Digital output jumpers
Digital output jumpers