AERCO Control System (ACS) - Manual (Page 32)

MC2: 04/23/13 Page 32 of 144
GF-131
AERCO Control System (ACS)
AERCO International, Inc. • 100 Oritani Dr. • Blauvelt, New York 10913 • Phone: 800-526-0288
Installation, Operation, and Maintenance Manual
OMM-0081_0D
2.10 INTERLOCK WIRING
The ACS is equipped with two interlocks designated Interlock 1 (INT 1) and Interlock 2 (INT 2).
Since both interlocks must be closed for the ACS to operate the boiler plant, the associated
wiring terminals are jumpered, prior to shipment. If desired, proving device switches can be
connected to either interlock in place of the jumper. If used, interlock wiring connections are
made as described in the following paragraphs.
DO NOT remove the factory-installed jumpers for INT1 or INT2
unless the respective Interlock is being connected to an external
proving device. The boiler plant WILL NOT operate if one or both
Interlocks remain open.
NOTE
If necessary, Interlock 1, Interlock 2 or both can be programmed to
operate the boilers only when the outdoor air temperature falls below
the system start temperature. The selection is made with “SYS
START INTLK” in the Relay Menu. The default is set to Interlock 1.
See paragraph 3.11 for details.
NOTE
NO power should be sent to the INT1, INT2, and SETBK terminals.
Only a dry contact may be applied.
2.10.1 Interlock 1 (INT 1) Wiring
Interlock 1 is often used with auxiliary equipment, such as air dampers or flow switches. It can
also be used as a general purpose interlock. If used, connect the end proving switch to INT 1
terminals 9 and 10 as shown in wiring diagram in Appendix E.
2.10.2 Interlock 2 (INT 2) Wiring
Similar to Interlock 1, Interlock 2 is a general purpose interlock which can be used with a variety
of devices or equipment or conditions that must be “proved” prior to enabling the boiler plant. If
used, connect the end proving switch to INT 2 terminals 11 and 12 as shown in wiring diagram
in Appendix E.
2.11 SETBACK WIRING
The SET BACK terminals, shown in the wiring diagram in Appendix E, are used only when
implementing a manually-controlled header temperature offset. If used, connect a dry contact
switch across SET BACK terminals 13 and 14. See the sub-section entitled Manual Offset
included in paragraph 3.8 (Field Adjust Menu),
2.12 RELAY WIRING
The ACS contains a System Start (SYS START) Relay, a Fault Alarm (FLT ALARM) Relay and
an Auxiliary (AUX) Relay which can be connected to external monitoring or control devices.
The contacts for each of these relays are rated at 120 VAC, 5A and are fused internally at 5A
with replaceable fuses. The contact terminals for these relays are shown in the wiring diagram
in Appendix E.
CAUTION ! !