TYPE 02 FROST CONTROL CABINET: MODE OF OPERATION
This control cabinet is intended for heating-cable installations with a maximum output of 2300W (three-phase), where the heating cable is installed for the frost protection of the floors of cold storage rooms, using thermostat control. The control cabinet is equipped with an alarm thermostat whose temperature sensor is placed next to the sensor of the operation thermostat. The alarm thermostat is fed from a separate phase with its own fuse which does not pass through an earth-leakage-circuit breaker. This is to ensure that the alarm does not stop functioning if the supply voltage for the heating coil should fail for some reason.
1 main switch
1 control switch, manual-0-automatic
2 Termonic 26090 thermostat including sensors
1 ELCB, two-pole 25/0,03A
1 enclosure, Class IP55
The control cabinet is intended for wall mounting and has cable entries on all sides.
Putting into service:
- Using a screwdriver, set the operation thermostat (Termonic) adjustment knob for the required temperature and make sure the temperature range is set to –15 – +95°C.
- Using a screwdriver, set the alarm thermostat (Termonic) adjustment knob for the required temperature, about +2°C, and make sure the temperature range is set to –15 – +95°C.
- Put the ELCB toggle switch in the ON position.
- Turn the main switch to the ON position.
- When the current has been switched on, the sensor LEDs light up indicating status as explained below.
Red LED lighting up: sensor fault or temperature range incorrectly set.
Yellow LED lighting up: thermostat operating (sensor temperature below preset value).
Change of temperature range in order to avoid end positions. An incorrect temperature range may led to a sensor malfunction being indicated.
The cabinet is connected to 2 separate phases: zero and earth.
The 4 x 1,5 mm² supply cable is connected directly to the main switch of the cabinet and to the neutral and earth terminal blocks.
The heating coils are connected to the cabinet’s earth terminal block (G-G), to the neutral terminal block (block 1), and to the outgoing phases L1 (terminal block 2).
The alarm is connected to a potential-free terminal with optional voltage. The sensor lead (integral, 3m) may be jointed up to a length of 50m without affecting temperature adjustment knob accuracy.
The sensor is connected to terminal block using 2 x 1.5mm². (For block numbering, see diagram).