nVent RAYCHEM VIA-DU-20 Controller


Multi-sensor controller for ramp heating and snow melting applications

RAYCHEM VIA-DU-20 is a multi-sensor control device for surface snow melting and de-icing applications.

The module provides control in combination with ground temperature and moisture sensors placed on the heated surface.  

The VIA-DU-20 is also used in:

  • SBS-xx-MV-20 Ramp heating control Panel for EM-MI-KIT installations
  • SBS-xx-VV-20 Ramp heating control Panel for EM2-XR installations
  • SBS-xx-CW-40 Ramp heating control Panel for EM4-CW installations
  • SBS-xx-CM-20 Ramp heating control Panel for EM2-CM installations
  • ACS-30-EU-VIA-DU-20-MOD for ramp heating sensor input of the ACS-30 solution.

As well as the integrated ground temperature and moisture sensor, the VIA-DU-20 also has an optional ambient temperature sensor used with the “Freezing Rain Precaution” feature. The unit also includes a basic BMS connection and alarm contacts for remote alarm function in the event of a fault.

Technical Specifications

RAYCHEM VIA-DU-20Technical information
Operating Voltage230Vac +/-10%, 50/60Hz.
Power Consumption14VA Max.
Main Relay (Heating)4A 250Vac, SPST, Voltfree
Alarm Relay2A 250Vac, SPDT, Voltfree
DisplayPoint Matrix 2 x 16 Places
MountingDin Rail
IP ClassificationIP20
Temperature Resistance0°C to 50°C.
Setpoint temperature1°C to 6°C (settable)
Moisture settings1 (low moisture) to 10 (high moisture)
Post-heating on time settings+30 minutes to +120 minutes
Non-volatile memory (Power failure)Yes, Parameters remain saved.

RAYCHEM VIA-DU-S20Ground Temperature and Moisture Sensor
Voltage8Vdc (Via the VIA-DU-20)
Sensor TypePTC
IP ClassificationIP65
Cable length15m, extendable to 50m (5 x 1.5mm²)
Temperature Resistance-30°C to +80°C.

RAYCHEM VIA-DU-A10Ambient Sensor
Sensor TypePTC
IP ClassificationIP54
Terminals1.5 to 2.5mm²
Sensor Cable2 x 1.5mm², Max 100m (Cable not included.)
Exposure Temperature-30°C to +80°C.


Warranty Information

Warranty Extension Available

Connection and Protection