DTW/DTB Flame-proof temperature monitor/limiter



  • 22 A switching capacity
  • Can be used directly in Zone 1 and 2
  • Flame-proof enclosure
  • ATEX, UL, CSA, FM Approval


Ex II 2G Ex d IIC T6
Ex II GD Ex tb IIIC T80 °C Db

Ambient temperature

device: -40 °C up to +60 °C
Operating temperature range sensor:
-40 °C up to +215 °C
Operating temperature range capillary tube:
-50°C up to +215°C


LCIE 08 ATEX 6073 X
IECEx LCIE 14.0005X
RTN PPC 00-38415


The flameproof encapsulated temperature controllers/limiters (DTW/DTB) are designed for (trace)-heating applications in the Ex area. They can be used both for protection against frost and for maintenance temperature applications. Heating units and other operating equipment are switched on and off by means of the temperature controller when the temperature is too high or too low. The DTB temperature limiter is designed with resetting lockout; resetting (restarting) is only possible on the device. Can be used for monitoring temperature in the air or on surfaces.


A change in temperature in the sensor causes a change in volume in the fluid filled in the measuring system, which in turn results in a movement of a membrane, which is connected to transmission mechanics and activates a microswitch. If the sensor temperature exceeds the pre-set level, the contact is actuated.

The temperature limiter switches off permanently if the temperature is exceeded. Once the temperature drops, the temperature limiter can be unlocked manually. If there is a break in the measuring system (leakage), the circuit remains open permanently.

Technical data *

Protection class IP 65 / NEMA 4, 7, 9
Dimensions Capillary tube: Length: 3000 mm, Diameter: 2 mm
Bending radius: 15 mm
Sensor: Length: 203 mm, Diameter: 8 mm
Material Enclosure: Aluminium die-casting, lacquered, with internal lid seal
Capillary tube made of stainless steel
Sensor made of stainless steel
Storage temperature -40 °C up to +60 °C
Weight 1.7 kg
Temperature range -4 °C up to +163 °C
Voltage AC 6/ 12/ 24/ 125/ 250/ 480 Volt, 50/60 Hz
Current Switching current for controller:
22 A at AC 6/ 12/ 24/ 125/ 250/ 480 Volt
Switching current for limiter:
16 A at AC 6/ 12/ 24/ 125/ 250 Volt, 15 A at AC 480 Volt
Connection Terminals: Terminal screws 4/2.5 mm² (AWG 10-14)
Cable entries: 2 x M 25 borehole

*Refer to the documentation for more detailed information


Data Sheet - DTW/DTB Flame-proof temperature monitor/limiter