Version
Document
Preliminary 003
Access V4.X Configuration manual
27 (33)
2019-05-13
When running variable speed drive-
controlled fans, the pressure signal from each respective fan’s
pressure transmitter is normally used as run indication signal. If the pressure or flow falls below the set
value during normal operation, a malfunction alarm is activated.
Data & Settings > Fan control > Supply air fan > Min pressure for supply air fan indication
Data & Settings > Fan control > Supply air fan > Min flow for supply air fan indication
There are two fan monitoring options if digital inputs are used for fan operation feedback. They can be
configured either for indication of the motor running or for monitoring of motor alarm contacts.
Configuration > Functions > Fan control >
An input configured for run indication should normally be closed during operation.
Open input when the motor is running, i.e. motor control output is activated, will generate an alarm.
For supply air fans and extract air fans, there is also a conflict alarm, i. e. an alarm if the run indication
input is closed even though the motor control output is not activated.
An input configured as motor protection should be normally open, i. e. closed contact when the motor is
running, i.e. motor control output is activated, will generate an alarm.
Fan levels
The controller supports up to three operation speeds (Low, Normal and High):
Configuration > Functions > Function Activation > Fan levels >
After activating operation speed levels the setpoint for each fan and each level can be set:
Data & Settings > Fan control > Fan setpoints >
Changing between the fan operation levels is done using the schedule by activating extended operation
function with digital input signals.
Fan compensation
Despite of active fan level, upon the need the actual fan speed can be adjusted by defining
compensation curves.
Configuration > Functions > Function Activation > Fan compensation curves > “Yes”
The function allows to set up to three independent curves. They can be used to set a compensation
based on the configured analogue input signal (temperature, pressure, flow humidity, CO2).
The compensation can be selected to apply to both fan or only one of the fan, to low, normal, high or all
speeds and only when defrosting.
Configuration > Functions > Fan compensation curves >
The curve has three parameter pairs which correspond to the value of the compensation at three
different related sensor values.
Data & Settings > Fan control > Fan compensation curves >