Mandik FDMB Manual page 8

Design .23, or .24 can be complemented with a terminal switch signaling of the damper blade
position "OPEN".
Design with covered control
mechanism 83.v2
Limit switch „OPEN"
Limit switch „OPEN"
Pulse switch
Pulse switch
Electromagnet (Solenoid)
Electromagnet (Solenoid)
Design with covered control
mechanism 83.v2
Limit switch „CLOSE"
Limit switch „CLOSE"
FDMB is always equipped by electric actuating mechanism BFL, BFN, BF 230-T or BFL, BFN,
BF 230-T (further only "actuating mechanism"). After being connected to power supply AC/DC
24V or 230V, the actuating mechanism displaces the damper blade into operation position
"OPEN" and at the same time it pre-stretches its back spring. When the actuating mechanism is
under voltage, the damper blade is in the position "OPEN" and the back spring is pre-stretched.
Time needed for full opening of the flap blade from the position "CLOSED" to the position "OPEN"
is maximum 140 sec. If the actuating power supply is cut off (due to loss of supply voltage, or
pushing the reset button on the thermoelectrical starting mechanism BAT), the back spring
displaces the damper blade into the breakdown position "CLOSED". The time of displacing the
blade from the position "OPEN" to the position "CLOSED" takes maximum 20 sec. In case that
the power supply is restored again (the blade can be in any position), the actuating mechanism
starts to re-displace the damper blade into the position "OPEN".
A thermoelectrical starting mechanism BAT, which contains two thermal fuses Tf1 and Tf2, is a
part of the actuating mechanism. These fuses are activated when temperature +72 °C has been
exceeded (the fuse Tf1 when the temperature around the damper and the fuses Tf2 when the
temperature inside the air-conditioning piping has been exceeded). After the thermal fuse Tf1 or
Tf2 has been activated, the power supply is permanently and irreversibly cut off and the actuating
mechanism, by means of the pre-stretched spring, displaces the damper blade into the
breakdown position "CLOSED".
Signalisation of damper blade position "OPEN" a "CLOSE" is provided by two limit switches.
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