Viconics VBZS Application Guide - Manual (Page 27)

27
Economizer Mode and CO
2
Level Control
If the fresh air damper is to be used for both free cooling and CO
2
level control (economizer mode and CO
2
level control, but without fresh air measurement station), only the Min Pos, Max Pos, Min CO
2
and Max CO
2
parameters as well as the free cooling sequence will be active.
- The FA Range parameter should be set to 0 CFM.
- Set AI4 parameter to CO
2
(0 VDC = 0ppm ; 10VDC = 2000ppm)
- Min Pos, Max Pos, Min CO
2
and Max CO
2
parameters should be set according to the required
setting.
Min Pos
Max Pos
Min CO
2
Max CO
2
Current
Fresh Air
Damper
Position
Current
CO
2
Level
The higher value between free cooling output and interpolation output between the above graphic
will be the signal sent to the fresh air damper.