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

auto

auto

6 = delayed switch off

auto

auto




11 = duty cycling

off

off




20 = frost protection

off

off

21 = fan failure

off

off




30 = fire override

off

off