Intrinsically Safe Incremental Encoder type IEI-1

Intrinsically safe incremental encoder type IEI-1 is designed to measure the rotation angle of equipment operating in group I hazardous areas (methane and/or coal dust explosion) as well as in group IIB hazardous areas. Thanks to its compact and solid design, it can be used in harsh operating conditions without the need for additional mechanical guards.

These encoders are designed in accordance with the good engineering practice with respect to their safety and meet the requirements of the standards PN-EN 60079-0 and PN-EN 60079-11.


  • rotational speed measurement,
  • overall dimensions.
Iskrobezpieczny enkoder inkrementalny typu IEI */*

Explosion protection

I M1 Ex ia I
II 1GD Ex ia tDA20 IP 66 IIB T4

Ambient temperature
-20°C to +70°C


Rated values

Ingress protection rating

Parameters of intrinsically safe outputs (2-3;2-4;2-5)
Io = 95,45 mA
Uo = 27,5 V
Po = 0,66 W
Co for I = 3,55 μF
Lo for I = 51,22 mH
Co for IIA = 2,24 μF
Lo for IIA = 31,22 mH
Co for IIB = 0,672 μF
Lo for IIB = 15,61 mH

Power supply parameters (1-2)
Ui = 28 V
Pi = 2,33 W
Ci – 0,6 μF
Li – 0 H

Number of incremental encoder pulses
up to 1024 pulses/rotation

Maximum rotational speed
up to 3600 rpm


I E I * / *

Supply voltage
2 – 5.6V DC
3 – 12V DC
4 – 15V DC

Type of data transmission
1 – One-wire signal
2 – Differential signal

Other parameters, including intrinsically safe ones, are included in the instruction manual available on the manufacturer’s website.