Version No. 1-4 - 28.04.2021
Doc. No. 9942681001
10 / 18
10. Electrical Connection
High electric voltage present. Installation, maintenance, cleaning and
any other work must be carried out by qualified personnel only. The
personnel must ensure that for the duration of this work the unit and
the cabinet are disconnected from the electrical supply and protected
against unauthorised/accidental reconnection.
Note: As soon as preperations are finished, mounting procedures may proceed.
Connection to the main electrical suppy
The mains connection is made via a connector / terminal block. To connect the unit to the mains proceed as
follows:
Take the control cabinet out of operation in the prescribed manner.
See the connection details on the circuit diagram.
Attention
Between contact T1 & T2 there is a 12V DC potential. These connections are to be connected to a door switch
only! If no door switch is used, these contacts are to be bridged and protected from unauthorized and/or
accidental external contact. Contacts P1, P2 & P3 are potential free and require an external power source if
wired to operate external components (indicator lamps, switches...). The load on these contacts is not to exceed
30V AC/DC, 5 A. If wired to external components it must be ensured that the wiring and connections are double
insulated and safe against touch and protected from unauthorized and/or accidental external contact.
Ensure that the correct polarity is maintained. The fans should have
clockwise rotation.
Fault warning connection
A fault warning contact for temperature in excess of the pre-set cabinet temperature is available and can be
connected as required. The operating current for this function must be less than 4A/30VDC, 4A/250VAC. The
fault warning is connected via terminals P1, P2 & P3 on the connection terminal block. The alarm temp.
adjustment range is between 25°C (left-hand stop) and 55°C (right-hand stop). The alarm temp. is preset at
50°C.
To change the alarm setting:
Remove the outer cover.
Remove the fixing screws from the PCB cover and the earth wire from inside it.
Lift off the PCB cover
Using a screwdriver turn the alarm temp. potentiometer on the PC-board slightly to the right (higher) or
the left (lower)
please note that the setting for the alarm signal must be at least 5°C higher than the setting for the
cabinet's internal temperature
Close the unit as prescribed
Check that the new setting meets requirements and if not repeat the above process.
Door contact switch connection
If required the unit can be switched on or off via a door contact switch (terminal T1&T2). When delivered the
door contact terminals are bridged.
To connect the door contact switch:
