User Manual

Overview
I/O Mix (Relay Assignment Matrix)
6
Siemens Industry, Inc.
Application Note, App 14901
140-1230
2020-02-11
I/O Mix (Relay Assignment Matrix)
In a heat pump application, the maximum number of compressors is two, with up to
two stages of auxiliary heat. The number of stages can be configured using the
BACnet points HeatStg, CoolStg, and AuxStg.
Table 2: Compressor System.
Compressor
Heating
Stages
Compressor
Cooling
Stages
Aux
Heating
Stages
Y1
Y2
W1
W2
O/B
0
1
0
Stage 1
Compressor
Cooling Only
N/A
N/A
N/A
N/A
0
2
0
Stage 1
Compressor
Cooling Only
Stage 2
Compressor
Cooling Only
N/A
N/A
N/A
1
0
0
Stage 1
Compressor
Heating Only
N/A
N/A
N/A
N/A
1
1
0
Stage 1
Compressor
Heating/
Cooling
N/A
N/A
N/A
Reversing
Valve
1
1
1
Stage 1
Compressor
Heating/
Cooling
N/A
Aux
Heat 1
N/A
Reversing
Valve
1
1
2
Stage 1
Compressor
Heating/
Cooling
N/A
Aux
Heat 1
Aux
Heat 2
Reversing
Valve
1
2
0
Stage 1
Compressor
Heating/
Cooling
Stage 2
Compressor
Cooling Only
N/A
N/A
Reversing
Valve
2
0
0
Stage 1
Compressor
Heating Only
Stage 2
Compressor
Heating Only
N/A
N/A
N/A
2
1
0
Stage 1
Compressor
Heating/
Cooling
Stage 2
Compressor
Heating
N/A
N/A
Reversing
Valve
2
2
0
Stage 1
Compressor
Heating/
Cooling
Stage 2
Compressor
Heating/
Cooling
N/A
N/A
Reversing
Valve
2
0
1
Stage 1
Compressor
Heating Only
Stage 2
Compressor
Heating Only
Aux
Heat 1
N/A
N/A