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MR387 Emergency Stop

MR387 E-Stop
MR387 E-Stop


Emergency Stop Sensor

The MR387 Series Emergency Stop Sensor Systems is a new, innovative emergency signaling system that can be deployed in hazardous environments or over long distances – beyond the capabilities of conventional electromechanical solutions. The MR387 E-STOP system employs a photo interrupt scheme operating over either a duplex multimode 50/125 or 62.5/125 μm optical link.

The MR387 E-STOP is designed for applications where a system needs to be deactivated when the E-STOP switch sensor is depressed or any system malfunction occurs.



ISO 13850 ISO 13850 defines the characteristics and requirements for a traditional electromechanical E-STOP switch. The MR387 Sensor/Controller integrates the definition of purpose and functionality only.
ISO 13849 Category 2 for MR380/MR387 E-STOP Sensor/Controller System
Functional Safety MR387 Sensor/Controller System = Category 2 per ISO 13849-1
MTTFd 6.20E+05 hours (70.8 years)
Performance Level PL=c
Safety Integrity Level SIL=1
Safe Failure Fraction SFF=97.85%
Diagnostic Coverage DC=75.76%
Functional States MR380 Controller Output States
Normal RESET (Up Position)

Red LED is OFF

Digital 5V and 24V Outputs=HI

Relay NC contacts=Closed, Relay NO contacts=Open

ACTIVATED (Down 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

Optical Interface
Interface Duplex LC for pigtailed sensors, MR387-X-YY where YY is pigtail length in meters
ODVA IP-LC connector receptacle, MR387-X-D00 sensors in housing
Insertion Loss

MR387-2-XX, 2.5 dB (2 dB Typical), LC-Duplex Pigtail, 62.5/125μm OM-1 MM Fiber

MR387-3-XX, 3.5 dB (3 dB Typical), LC-Duplex Pigtail, 9/125μm OS-1 SM Fiber

MR387-5-XX, 3.5 dB (3 dB Typical), LC-Duplex Pigtail, 50/125μm OM-2 MM Fiber

Consult Application Note AN118 for guidance on determining system loss budget and maximum distance

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
NEC Exempt
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 2500 meters
  • Multiple E-STOP switches can be connected in series


Call 805.389.6600