CIAT AirControl CTA Manuel De Régulation page 72

1.5.5 Fan motors
The motor or motors start when the unit is in "On" mode.
The alarm information fed back from the motor or motors allows their protection to be monitored during an on request via KV1
and KV2. If one or other of these signals is not received, the unit is stopped and the faults are signalled.
Their rotation speed is controlled using one of the 3 following modes:
1. fixed ("Without"), which means that the motors are controlled directly with no variable drive
2. to maintain the fans at a constant flow ("Flow rate") in accordance with the setpoint(s) on page w0, based on the configuration
on page p3 of the "Settings parameters" menu and the air quality setpoint (option) until the maximum flow rate limit on page w3
is reached.
3. to maintain a constant pressure in the supply air duct ("Pressure") in accordance with the setpoint on page w1 and based on
the configuration on page p3 of the "Settings parameters" menu.
Control modes available for the management of fans
Without (fixed)
MS
1.5.6 Air flow rate
The presence of air flow in the unit is detected in two different ways depending on the fan control type configuration:
• Fan flow rate control:
The measurement used is the differential pressure on the supply air fan to manage the supply air flow rate
The measurement used is the differential pressure on the return air fan to manage the return air flow rate
• Other types of fan control:
The measurement used is the differential pressure on filter 1 to manage the supply air flow rate
The measurement used is the differential pressure on filter 2 to manage the return air flow rate
1.5.7 Filtration
3 different filters can be monitored simultaneously: 1 in the Supply air flow, 1 in the Return air flow and 1 additional filter in either
of the 2 flows.
To check their fouling level, each filter is equipped with a differential pressure sensor which measures its upstream/downstream
pressure drop. This sensor has a measuring range of 0-1000 Pa
Flow rate
SP
+
∆ρ
0
SP
∆p
Gravimetric filter
-
MS
10Pa
10 Pa
Débit
Sufficient
d'air
air flow
suffisant
EN - 6
Pressure
+
MS
Pa
measure-
mesure
ment
SP
∆p
Bag filter
SP
-
∆ρ