1-pole fail safe temperature limiter, safety sensor

1-pole fail safe temperature limiter, safety sensor

These safety devices automatically switch off the current in the controlled circuit as the temperature is reached, and switch it on again as the tepmerature falls below the set threshold value. The temperature of the controlled medium is thus maintained within a narrow zone. The limiter makes a last full annexation in case of mechanics injury.

Working tepmerature range: 120 – 355 °C
Areas of application:
- water heaters, hot water storage tanks
Trouble-free operation is conditioned by proper heat transfer between the controller's sensor and the controlled medium.


Lifetime: 1000 switching cycles Working range: 120-355 °C 
Switching power:  30(4)A-4(1)A/250 V~ Conductive connection: A6,3X0,8 tab contact
A6,3X0,8 tab contact – M3 screw terminal
20(4)A-4(1)A/250 V~
16(4)A-4(1)A/400 ~V
Way of operation: 1AGKLM   M3 screw terminal                 
Max.temp. for the main unit: 85 °C / 150 °C Capillary tube: Ø 1,6 (INOX)
Protection class: Class 0. / IP 00 Capillary tube length: 2400 mm 
Operation environment: Normal of bulb: Coiled inox tube: INOX: Ø 6;
Heat and fire resistance: D Max. bulb temperature: Max. working temperature +15%
Leakage current resistance: ≥175 Manual reset temp.: 25 ± 5°C


Type Code Type mark Dial scale
ØD x L1/mm/
Capillary tube
Ød x L2 /mm/
Protection tube
L3 /mm/
5276-0-151-0 BTB-12-01 160 +0 -12 6,1 x 48 Inox 2 x 1650 1480  M
5276-0-151-1 BTB-12-01 320 +0 -14 6,1 x 48 Inox 2 x 1540 1150  M
5276-0-151-2 BTB-12-01 255 +0 -14  6,1 x 48 Inox 2 x 905  750 M