MR381 Emergency Actuator

MR381 Emergency Actuator

Emergency Actuator Sensor

The MR381 Series Emergency Actuator (E-ACTUATOR) Switch is a new, innovative emergency signalling system that can be deployed where EMI immunity is required, in hazardous environments or over long distances – beyond the capabilities of conventional electromechanical solutions. The MR381 E-ACTUATOR system employs a photo interrupt scheme operating over either a duplex multimode or duplex single mode optical link.

The MR381 E-ACTUATOR is designed for safety applications where a system is not to be activated or powered, such as a fire suppression system, until the E-ACTUATOR is deliberately pushed and engaged. A malfunction of the system shall not activate the emergency event.


ISO 13849 Category 2 for MR380/MR381 E-ACTUATOR Sensor/Controller System
Functional Safety For Function Safety applications, please refer to MR387 E-Stop Sensor System
Functional States MR380-1 Controller Output States
Normal RESET (Up Position)
Broken Fiber, Loss of Optical Signal or Controller Failure

Red LED is ON

Digital 5V and 24V Outputs=LOW

Relay NC contacts=Open, Relay NO contacts=Closed

ACTIVATED (Down Position)

Red LED is OFF

Digital 5V and 24V Outputs=HI

Relay NC contacts=Closed, Relay NO contacts=Open

Optical Interface
Interface Duplex LC for pigtailed sensors, MR381-X-YY where YY is pigtail length in meters
ODVA IP-LC connector receptacle, MR381-X-D00 sensors in housing
Insertion Loss

MR381-2-XX, IL=2.5dB max (2dB typical), 62.5/125 OM1 MM Fiber

MR381-3-XX, IL=5.0dB max (3dB typical), 9/125 OS1 SM Fiber

MR381-5-XX, IL=3.5dB max (3dB typical), 50/125 OM2/OM3 MM Fiber

Explosive Atmospheres Inherently Safe, Simple Mechanical Device
EX Classification Inherently safe, simple mechanical device when used with MR380 Multimode Controller
IECEx Test Report GB/CML/ExTR 16.0105.00/00
IEC Ex EPL Mb/Gb/Gc/Db/Dc
North America Exempt, non-electrical
Temperature/Humidity -40°C to +65°C (-40°F to +150°F), 0-95% RH, Non-Condensing
Ingress Protection IP61
Housing Aluminum body, anodized finish
Durability 100,000 operations min.
Housing Dimension Consult Mechanical Reference Drawing
Mounting Consult Mechanical Reference Drawing
Unit Weight Sensor with 5 meter pigtail, 240 g (8.5 oz)

Specifications subject to change without notice


  • Sensor is EX classified “inherently safe, simple mechanical device”
  • Sensor can be operated in any hazardous or explosive environment – gas, dust or mines
  • Immune to EMI, RFI, lightning, and ground loops
  • Immune to high voltage lines
  • Panel mountable sensor
  • DIN rail mountable controller
  • Controller provides DPDT relay and digital signal outputs
  • Operates over long distances – up to 10km (6 miles) with single mode fiber
  • Multiple E-STOP switches can be connected in series

    Ordering Information

    MR381-XY-CZZ Fiber Optic E-Actuator with Duplex LC Pigtail
    where X=Fiber type: 2=OM1 62.5/125 MMF, 3=OS1 9/125 SMF, 5=OM2 50/125 MMF
    where Y=Mushroom Button Size: S=Small=30mm OD, M=Medium=40mm OD
    where ZZ=Pigtail Length: C1R5=1.5m, C03=3m
    Contact Micronor sales for OEM custom pigtail lengths
    MR381-XY-D00 Fiber Optic E-Actuator in IP Housing:
    where X=Fiber type: 2=62.5/125 MMF, 3=9/125 SMF, 5=50/125 MMF
    where Y=Mushroom Button Size: S=Small=30mm OD, M=Medium=40mm OD
    where D00=Housing with IP-LC Interface

    MMF=Multimode Fiber, SMF=Single Mode Fiber


    Quick Ship Configurations

    MR380-0-1 OEM Multimode Controller Board, Standard Temperature
    MR380-0-1E OEM Multimode Controller Board, Extended Temperature
    MR380-1-3 Universal Single Mode/Multimode DIN Rail Mount E-Stop and Switch Controller Module
    MR381-2S-1R5 E-Actuator Sensor with OM1 62.5/125 MMF Pigtail Length=1.5m
    MR381-2S-03 E-Actuator Sensor with OM1 62.5/125 MMF Pigtail Length=3m
    MR381-2S-D00 E-Actuator Sensor in Housing with OM1 62.5/125 MMF IP-LC Interface
    MR381-3S-1R5 E-Actuator Sensor with OS1 9/125 SMF Pigtail Length=1.5m
    MR381-3S-03 E-Axctuator Sensor with OS1 9/125 SMF Pigtail Length=3m
    MR381-3S-D00 E-Actuator Sensor in Housing with OS1 9/125 SMF IP-LC Interface