Plant mode
During normal operation, the air handling unit control strategy will control the fan speed.
The input "PlantMode" input from the control strategy module is decoded to provide the required fan speed signal. The table below shows fan overrides depending on the "PlantMode".
Notes:
Fire overrides have the highest priority over plant mode overrides.
Plant mode |
Stage1Cmd |
0 = off |
off |
1 = optimum start |
auto |
2 = night cycle |
auto |
3 = night purge |
auto |
4 = occupied period |
auto |
5 = extended operation |
auto |
6 = delayed switch off |
auto |
11 = duty cycling |
off |
20 = frost protection |
off |
21 = fan failure |
off |
30 = fire override |
off |