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We reserve the right to make technical changes | 83055600dUK – Translation of the original instruction manual (HMD 2) | ait-deutschland GmbH
ASSEMBLY AND INSTALLATION OF SENSORS
External sensor
The external sensor (protection class IP 67) is a function-critical
accessory and included in the scope of supply.
NOTE
If the external sensor is not installed or defective, the heat-
ing and heat pump regulator automatically sets the exter-
nal temperature to -5 °C. The status display of the control
unit lights up red, the screen of the control unit reports an
error.
IMPORTANT
Mount the external sensor on the north or northeast side
of buildings. The sensor must not be exposed to direct
sunlight. The cable gland must point to the base.
1. Open the housing of the external sensor and align ≥ 2 m
over the base of the fastening point.
1 Quick-release screws
2 NTC sensor element 2.2 kΩ at 25 °C
3 Cable clamps
4 Housing sealing in housing cover
2. Mark the fixing holes on the fixing point and drill them into
the fixing point. Insert dowels and screw the housing of the
external sensor to the wall.
NOTE
Dowels and screws for fastening the external sensor are
not included in the scope of supply.
3. Loosen cable gland and lead a 2-wire cabel (Ø 5 - 9,5 mm, cross
section ≤ 1.5 mm² per wire, cable length ≤ 50 m) through the
cable gland into the housing.
4. Fit the cable wires with wire end sleeves, place them on the ca-
ble clamps of the external sensor and tighten them with a torque
of 0.5 Nm.
5. Tighten cable glands with a torque of 2.5 Nm and close the
housing of the external sensor. Ensure that the housing seal
and the sealing surfaces are clean and that the housing seal is in
the correct position.
IMPORTANT
No moisture may be trapped in the housing. If necessary,
completely dry the inside of the housing before mounting
the housing cover.
Ensure that the tightness of the housing is guaranteed by
mounting it tension-free and that no water can penetrate
the housing of the external sensor at any time (for instance
during the construction phase).
CONNECTIONS OF THE CONTROL UNIT
R RS485 for connecting the
room control unit (RBE)
N Network
L LIN-BUS to the control board
S not assigned
