Access Configuration Manual

The filter monitoring function can handle up to 5 filters:

• Supply air pre-filter
• Supply air filter
• Supply air end-filter
• Extract air pre-filter
• Extract air filter

The intended filter placement in the AHU is as follows:

Filter condition can be monitored either by guard or sensor. In both cases the filter alarm is triggered when over pressure is detected.

The Guard uses a digital pressure switch. The switch activates if pressure drop across the filter is higher then manually preset limit.

The Sensor uses a differential pressure transmitter. Filter monitoring is made air flow dependent. This means that a higher pressure drop is permitted across a filter at a higher air flow.
The linear dependency of flow-pressure drop can be adjusted manually or set via calibration.

Each of the filter monitors has a dedicated alarm to point out the dirty filter.

Filter sensors or guards are also being monitored for valid readings - malfunction (e.g. wire break) triggers a sensor error alarm.

Periodic filter replacement can be set in addition to or instead of pressure drop monitoring. Upon the end of the period, the service interval alarm will be triggered.