Mounting and installation - Basic Documentation - RDF302 - RDF302.B - RDF302/VB

Semi-flush mount room thermostats with RS485 Modbus communications RDF302, RDF302.B, RDF302/VB

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Thermostats (temperature controller with sensor)
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Technical Documentation > Basic Documentation
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Mount the room thermostat on a recessed square conduit box with 60.3 mm fixing centers. Do not mount on a wall in niches or bookshelves, behind curtains, above or near heat sources, or exposed to direct solar radiation. Mount about
1.5 m above the floor.

  • Mount the room thermostat in a clean, dry indoor place without direct airflow from a heating / cooling device, and not exposed to dripping or splash water

  • In case of limited space in the conduit box, use mounting bracket ARG70.3 to increase the headroom by 10 mm


See Mounting Instructions M3079 enclosed with the thermostat.

  • Comply with local regulations to wire, protection and earth the thermostat.

  • The device has no internal fuse for supply lines to fan and actuators. To avoid risk of fire and injury due to short-circuits, the AC 230 V mains supply line must have a circuit breaker with a rated current of no more than 10 A.

  • Properly size the cables to the thermostat, fan and valve actuators for
    AC 230 V mains voltage.

  • Use only valve actuators rated for AC 230 V

  • The wiring cross section used for power supply (L, N), fan/relays (Qxx) and
    230 V outputs (Yxx -N) must be adapted to the preceding overload protection elements (max 10A) under all circumstances. Comply under all circumstances with local regulations.

  • Cables of SELV inputs X1-M / X2-M: Use cables with min AC 230 V insulation, as the conduit box carries AC 230 V mains voltage.

  • Inputs X1-M or X2-M: Several switches (e.g. summer / winter switch) may be connected in parallel. Consider overall maximum contact sensing current for switch rating.

  • Isolate the cables of Modbus communication input +, - and REF for 230 V.

  • No metal conduits.

  • No cables provided with a metal shield.

  • Disconnect from supply before opening the cover.