4
McQuay IM 660-3
Configurable Relay Outputs
The MicroTech 2000 WSHP controller provides one relay
output that can be configured for the following four options:
•
Boilerless system (skin heat) relay
•
Motorized water valve relay
•
Fresh air damper relay
•
Timed output relay (L
ON
W
ORKS
only)
These options can affect installation requirements and unit
control. If more than one configurable relay output option is
required, the MicroTech 2000 WSHP auxiliary board is
required to provide the other three outputs. The MicroTech
2000 WSHP auxiliary board typically is factory mounted only
in 2-compressor-circuit WSHP units. Only three relay outputs
are available for use as configurable relay outputs in 2-circuit
WSHP units. All configurable relay outputs are set to “no
function” by default and must be field configured. A
description of the four relay options follows.
Boilerless System/Auxiliary Heat Relay
(L
ON
W
ORKS
only)
The relay receives loop water temperature input from the
MicroTech Loop Water Controller through the gateway panel
and provides relay output to electric heat on a call for heat
after loop temperature falls.
Boilerless System/Auxiliary Heat Relay
(L
ON
M
ARK
only)
The relay output energizes when the space temperature reaches
the heating set point and de-energizes when the space
temperature exceeds the heating set point plus a configurable
differential set point (defaulted to 3°F).
Motorized Valve Relay
The relay provides output to the motorized valve to shut off
water through the unit when the compressor is not operating.
Fresh Air Damper Relay
The relay provides output to the open damper whenever the
fan is operating in the occupied cycle.
Timed Output Relay (L
ON
W
ORKS
only)
The relay provides output to an auxiliary load to control its
operation based on a specific time schedule different from that
of the heat pump unit.
Figure 1: First control signal output
Figure 2: Second control signal output
Figure 3: Third control signal output
Figure 4: Fourth control signal output
1
2
3
4
5
6
7
E
L
U P
C
Terminal boards
(located externally on the WSHP chassis)
24 VAC
pilot duty relay
(by others)
IMPORTANT:
To use onboard 24 VAC,
change the jumper PF1 on the
MicroTech 2000 controller
from factory default pins 1 and 2 to
pins 2 and 3.
4
3
2
1
(by others)
24 VAC
24 VAC
Terminal located on
MicroTech 2000 auxilliary board
J6
24 VAC
pilot duty relay
(by others)
Use contacts as needed for option.
4
3
2
1
(by others)
24 VAC
Terminal located on
MicroTech 2000 auxilliary board
J7
24 VAC
pilot duty relay
(by others)
Use contacts as needed for option.
4
3
2
1
(by others)
24 VAC
Terminal located on
MicroTech 2000 auxilliary board
J10
24 VAC
pilot duty relay
(by others)
Use contacts as needed for option.
