Heating - WMT700

WMT700 Series User Guide

Document code
Document type
User guide

Heated WMT700 sensors have the following symbol.

The sensor can be hot during normal operation. Avoid touching the sensor in operation. The sensor may detect touching as an ice blockage and start the high power melting mode.

Do not touch hot surfaces. Wear protective gloves when working with WMT700.

Let WMT700 cool down for 20 minutes after disconnecting the heating power supply.

Heated versions of WMT700 are only intended for outdoor applications.

In addition to the standard non-heated version, WMT700 can include a heating functionality that ensures proper operation in cold environmental conditions or in cases where snow and ice build-up is possible.

WMT700 has the following heating options that can be preconfigured at the factory according to your order:

Make sure that the supply output power capacity is high enough especially when transducers, array arms, and sensor body are equipped with heaters. Note that there are individual connections for applying the heating voltage.
Table 1. Maximum power consumption
Heating Maximum peak power
Heated transducers Average 32 W at 24 V

Peak 40 W at 24 V

Heated transducers and arms Average 152 W at 24 V

Peak 200 W at 24 V

Heated transducers, arms, body Average 252 W at 24 V

Peak 350 W at 24 V

Heating is controlled with pulse width modulation so that the average power consumption is as in the table above.
  • Transducer-and-arm heating has a 1-second timespan. Maximum power peak is always less than 1 s. For the average power of 1 s, see the following figure.
  • Body heating has a 10-second timespan. The average power is always limited as shown in the following figure.

If higher heating supply voltages are used, the peak power increases.

Figure 1. Average power consumption

With a low supply voltage, the power peak gets longer and approaches the average power.