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11.6 Command from supervisor
This function allows direct control of the internal fans of the unit by sending a ventilation command to the controller from the
supervision system.
The fan speed is changed according to the last command received. This means that if communication fails between the controller
and the supervisor, the fans will continue to run at the same speed of the command received before communication failure.
The protection functions of the fans, like the Safety Reduction Load, always take priority and switch off the unit when one or
more blocking alarms are activated.
11.7 Management of internal fan alarms
In units with AC or EC fans connected via digital output, the alarm contacts of the fans are connected directly to the digital
contact for the Lack of Air Flow blocking alarm (A101).
In units with EC fans connected via Modbus, the events of each fan are managed independently. The generation of the blocking
alarm depends on the number of fans on the unit:
1.
Unit with one fan
The presence of alarm events coming from the fan also triggers the Lack of Air Flow alarm, which blocks the entire
unit.
2.
Unit with several fans
The presence of alarm events coming from a single fan does not block the unit but brings to 100% the request sent to
the remaining fans (made evident by the presence of the
decrease in flow rate.
The presence of alarm events coming from at least two fans simultaneously triggers the Lack of Air Flow alarm,
which blocks the entire unit.
Fan signalling events (Generic Warning) are always non-blocking.
Version 38
icon on the main mask) in order to compensate for the
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