Emerson Autochangeover Controllers AC8 - Manual (Page 10)

Introduction
2
1.5 Outside Enclosure Overview
The AC8’s controller board comes in an enclosure that is 2-3/4" deep and has a built-in liquid crystal
display (LCD) and a key lock, as shown in Figure 1. The enclosure is made of metal to accommodate
secure conduit fittings and protect components against environmental debris.
Figure 1 AC8 enclosure—external features
The enclosure houses the controller board and Transformer Module, as shown in Figure 2.
The enclosure must be secured to a wall, either flush-mounted or recessed in the wall, as described in
2.0 - Installation. Knockouts and access slots on the top and bottom allow easy connection of wires
and cables (see 3.0 - Wiring and Connections) with either mounting type.
Figure 2 AC8 enclosure—internal features
LCD for configuration
and operation
Key lock
The enclosure
has knockouts
and access slots
on top and
bottom for
cables and wires.
BAR CODEBA R C
OD
E
LIEBERT
START TB7:
V INPU UTT 24VV INPU UTT
+ —
+ —
(TOP) ON
(BOTTOM)
0: COMMS MS
485
TB3:
RELAY
OUTPUTS
TB2: CONTACT INPUTS ASS
REV
(BOTTOM) (TOP) 4
3
2
1
(BOTTOM) 8
7
6
5
(BOTTOM) (TOP) 4
3
2
1
(BOTTOM) 8
7
6
5
J11: PHONE PIN 3-TIP PIN 4-RI"N"G
MODEM
TB5: COMMON ALARM (TERMINAL BLOCKS ROTATED IN VIEW)
(BOTTOM)
BOTTOM
Q11 R26 R402 P11
+ LS1
NO NO NO N ALARM SENS TOP
ENABLE AUDIBLE
(TOP) NO C NC NO C NC
ALL CIRCUITS;
CLASS 2
TB9: ANALOG GROUND
+ + — —
+ — + —
3-4 BOTTOM 1-2 TOP
Back of LCD
Transformer Module
Controller Board
Ground wire
for LCD
On/Off switch
for Transformer
Module
Knockouts and
access slots
(top and bottom)
Power receptacle
(115VAC model only)