Fläkt Woods
3099 US 03.02
20
Specifications are subject to alteration without notice
PUMA (A–F) Rotary heat exchanger
TECHNICAL HANDBOOK
Control
Example 4. Speed detector
Variable speed:
The speed detector monitors the rotor
speed. An alarm will be initiated if the rotor speed is
lower than that demanded by the speed controller. The
magnet, magnetic sensor and mounting bracket are
included in the supply.
Constant speed: The speed detector consists of a mag-
net, a magnetic sensor and an alarm relay. The alarm
relay is preset for an alarm delay time of 120 seconds.
This time corresponds to the lowest rotor speed of
approximately 0.25 rpm. In order to avoid an alarm
when the rotor is intended to be stationary, the alarm
relay should be wired so that an alarm can be initiated
only when the system requires heating or cooling energy
recovery (see the instructions).
Rotor
Magnet
Impulsgivare
Larm, lampa e.dyl.
Larmrelä
Fig. 16b
Fig. 16a
Nät
220 V
RC
RPM
Rotor
Fästplåt
Magnet
Impulsgivare
Magnetic
sensor
Mounting bracket
200 V
supply
Magnetic sensor
Alarm relay
Alarm, alarm lamp or the like
Magnet
Magnet
Example 2. Heating and cooling energy recovery
The temperature sensor 5 maintains the exhaust air
temperature or room temperature constant via the con-
trol unit 4 which, on a drop in outdoor air temperature,
begins by reducing the cooling output. If the sensor 2
senses a higher temperature than sensor 3 , the rotor will
run at maximum speed, which is known as summer case
control. If no cooling is carried out and the temperature
drops further, the rotor speed will increase. At maximum
speed and increased heat demand, the supply air temper-
ature is controlled by means of the reheater.
1 Speed controller
2 Temperature sensor
3 Temperature sensor
4 Control unit of a make available on the market
5 Temperature sensor
6 PUMZ - 21 or equivalent differential thermostat
Example 3. Cooling energy recovery - maximum speed
If the temperature sensors 2 and 3 of the differential
thermostat sense that the supply air temperature is higher
than the exhaust air temperature, the motor will run at
maximum speed for cooling energy recovery.
Rum
RC
RPM
DM
~
DT
1
3
2
~
~
Rum
1
3
2
RC
RPM
DM
DT
6
5
4
RC
T
ST
SV
SV
+
–
Fig. 14
Fig. 15
Room
Room
1 PUMZ - 21
differential thermostat
2 Temperature sensor
3 Temperature sensor
are included in 1
}
are included in 6
}