Chromalox WTPM WeatherTrace Freeze Protection Panel


  • Standard NEMA 4 Enclosures
  • NEMA 4X Stainless Steel Enclosure Option
  • Hand/Off/Auto Selector Switch
  • 15, 20, 30, 40, and 50 Amp Single pole and Double-pole 30mA Ground Fault Thermal-Magnetic Circuit Breakers
  • 208/120 VAC 3-Phase, 4-Wire
  • 240/120 VAC Single Phase, 3-Wire
  • 480/277 VAC 3-Phase, 4-Wire
  • 50 to 250 Amp Main Breaker
  • Ambient and Line Sensing Control
  • Enclosure Heater Options for Condensation Prevention or Freeze Protection on Outdoor Installations
  • UL and cUL Third Party Approvals

The Chromalox WTP series freeze protection heat trace panels offer power distribution, ground-fault protection, individual circuit alarming, and ambient sensing control. The panels are housed in NEMA 4 enclosures for indoor/outdoor applications. NEMA 4X 304 stainless steel enclosures may be selected as an option for more harsh environments. The WTP units can be configured with 50 to 250 Amp main breaker ratings in Single and Three-Phase configurations. Branch circuit breakers are available in 15, 20, 30, 40, and 50 amp single-pole and two-pole configurations with 30mA ground-fault equipment protection.

The WTPM WeatherTrace with the HMI Monitoring, continually monitors the supply voltage to each individual heat trace circuit. Loss of voltage or a ground fault condition will trigger an automatic alarm condition, alerting plant personnel of critical process problems and reducing downtime. An annunciator panel then identifies the faulted zone and a Common Alarm is activated with the re-ring feature. The WTPM panels provide group control of multiple heat trace circuits for pipe freeze protection via an ambient sensing thermostat, electronic controller or door mounted HMI. The WTPM can also be configured for group control of snow melting or deicing applications using our internal temperature/moisture controller. Chromalox recommended controllers include: ChromaMelt-2R, RTAS, RTBC, or TPR with HMI. The WTPM may be operated in two modes; automatically with the external controller or in manual override via the Hand/Off/Auto selector switch.


Power Source 208/120 VAC 3-Phase, 4-Wire
240/120 Single Phase, 3-Wire
480/277 VAC 3-Phase, 4-Wire
Ambient Operating Temperature -40˚F to 104˚F (with Enclosure Heater)
Incoming Wire Size 50 – 100A MCCB, 14 – 3/0 AWG
200 – 250 A MCCB, 3/0 AWG – 350 kcmil
Load Wire Size 18 – 8 AWG (15 – 30 Amp C.B), 18 – 6 AWG (40-50 Amp C.B)
Ground Fault Breaker Type 30mA Ground Fault Equipment Protection
Enclosure NEMA 4 or NEMA 4X 304 Stainless Steel (option)
Main Breaker Size 50-250 Amp Two-Pole Main Disconnect Switch  with through Door Rotary Handle
50-250 Amp Three-Pole Main Disconnect Switch  with through Door Rotary Handle
Approvals  UL and cUL


Chromalox WeatherTrace WTP-WTPM Freeze Protection Panel_DpstarGroup