Hengstler Incremental Encoders ISD25

Hengstler Incremental Encoders ISD25

The intrinsically safe optical ATEX hollow shaft encoder ISD25 with a shaft diameter of up to 19.05 mm works reliably in the temperature range from -40 ° C to +100 ° C. This type of encoder with a hard-anodized housing design exceeds the requirements of protection class IP66 / IP67 and NEMA 6. By using the latest OptoASIC technology, the encoder is insensitive to shock and vibration. The rotary encoder type HSD25 can be easily installed on the motor and thus enables reliable feedback signals under rough ambient conditions.

This robust encoder is also available in Stainless Steel to meet NEMA 4x and 6P requirements and its sealed housing allows the Encoder to be operated when regulatory washdown and high pressure steam or caustic chemicals are required. Utilization of an advanced Opto ASIC with innovative packaging techniques enables the encoder to operate in high shock and vibration environments. The ISD25 is also available in an Intrinsically Safe version certified to ATEX EEx ia IIB T4 when used with the appropriate IS barrier.


  • One-or two-channel versions
  • Optional adaptive line driver
  • ATEX- certification for intrinsically safe devices
  • High-resolution, unbreakable code disc
  • Standard industrial plugs
  • Ingress protection NEMA 4X, IP67
  • Available with housing made of nickel or stainless steel

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Product FamilyISD25
Ordering InformationRotary Encoder ISD25
Function / ApplicationIncremental
Housing Diameter [mm]58 mm
Solid- / Hollow ShaftHollow 6 ... 19 mm
Protection Rating HousingIP67
Operating Temperature [°C]-40 ... +80 °C
Housing OptionStainless Steel
 Nickel Finish
 powder coated alumunium
Increased Environmental RequirementsHigh mechanical robustness
 Ex atmosphere
 CSA approval
Revolutions [rpm]5.000 rpm
Number of Pulses1 ... 3600
InterfaceDifferential Line Driver
 Open Collector NPN

Download Data Sheet: Incremental Encoders ISD25

Ref: hengstler.de