Notes for Intrinsically Safe Applications

Specifying Sensors for Ex ia Circuits
All thermocouple and RTD sensors shown in this catalogue are suitable for use in intrinsically safe (IS) applications to Zone 0 when used with an appropriate barrier. The full classification is Ex II 1 G Ex ia IIC Ga. The mineral insulated construction gives suitable insulation resistance between conductors (minimum 1000 M Ω) to guarantee conformance.

The barrier isolates the signal from the hazardous area and no further certification of the sensor is necessary.

When a 4~20mA transmitter is selected this is also Ex ia approved. When specifying sensors for IS areas please add IS after the type reference i.e. 52-IS and we will provide the following documentation with the order:
  • TC Ltd Ex ia certificate of conformity & letter of conformity from TrAC Global Ltd (our notified body)
  • Ex ia tags
  • ATEX certificate for transmitter (if required)
  • All cables are supplied with blue outer sheath
  • All terminal heads are supplied in stainless steel (die cast alloy is not permitted in IS areas)