Plant mode
During normal operation, the air handling unit control strategy will control the fan speed.
The input "PlantMode" from the control strategy module is decoded to provide the required fan speed signal. The table below shows fan overrides:
Plant mode |
Stage1Cmd |
Stage2Cmd |
0 = off |
off |
off |
1 = optimum start |
auto |
auto |
2 = night cycle |
auto |
auto |
3 = night purge |
auto |
auto |
4 = occupied period |
auto |
auto |
5 = extended operation |
auto |
auto |
6 = delayed switch off |
auto |
auto |
11 = duty cycling |
off |
off |
20 = frost protection |
off |
off |
21 = fan failure |
off |
off |
22 = overheat protection electric heater |
off |
off |
23 = emergency stop |
off |
off |
30 = fire override |
off |
off |