Main menu

Safety Relays

The Guardmaster® MSR100 Single-function Safety Relays support a wide variety of input devices and output configurations. Ideal for relatively small safety applications and single zone control, MSR100 relays are compact packages with removable terminals. These relays are also available in electromechanical versions, or solid-state models for applications involving high cycle rates. Note that Guardmaster Safety Relays have been marketed by Rockwell Automation under the trade name "Minotaur" in the past.

MSR123RT

      

MSR123RT

The Allen-Bradley Guardmaster Minotaur MSR123RT is a safety monitoring relay that provides two normally open safety contacts and a solid state auxiliary output for use with interfacing to PLCs.  The MSR123RT can be connected to either a single or dual channel safety gate or e-stop, or can be connected to a light curtain that provides cross fault detection.  Reset and output monitoring is determined by the wiring configuration. Automatic/manual reset can use a jumper or can be used to check operation of external contactors. Monitored manual requires the use of a manually operated normally open momentary switch.  The MSR123RT has 2 normally open safety rated outputs. The safety outputs have independent and redundant internal contacts to help ensure the safety function. The solid state auxiliary output is a PNP circuit with short circuit protection designed to indicate the status of the MSR123RT.

  • Category 4 per EN 954-1
  • Stop category 0
  • 2 Safety contacts N.O.
  • 1 Solid state PNP auxiliary contact
  • Single/dual channel operation 
  • Cross fault monitoring 
  • Monitored or automatic reset 
  • E-stop, safety gate or light curtain applications
 MSR126R T  

MSR126R/T

The Allen-Bradley Guardmaster Minotaur MSR126R/T is a safety monitoring relay that provides the very basics for safety control systems in a 22.5 mm package. The MSR126R/T is designed for connection to a single channel safety gate, a single channel e-stop or a light curtain that provides cross fault detection. The MSR126.1R/T is designed for connection to a dual channel safety gate or e-stop, as it performs cross fault detection across the inputs. The MSR126R and MSR126.1R are designed for applications where a monitored manual reset is required. Monitored manual reset requires the use of a momentary normally open switch to activate the outputs.  The MSR126T and MSR126.1T are designed for applications where automatic/manual reset is required.  The outputs are only two normally open safety-rated outputs. The safety outputs have independent and redundant internal contacts to support the safety function.

  • Category 4 per EN 954-1
  • Stop category 0
  • Two safety contacts N.O.
  • Single/dual channel operation 
  • Cross fault monitoring 
  • Monitored or automatic reset 
  • E-stop, safety gate or light curtain applications
 MSR127RP TP  

MSR127RP/TP

The MSR127RTP can be connected in three different input wiring configurations: one normally closed, two normally closed, or with two PNP connections from a light curtain. When connected in the two normally closed fashion, the MSR127RTP checks for cross faults across the two inputs. When connected to light curtains, the light curtain must perform the cross fault detection.  The MSR127RP has a monitored manual reset. The MSR127TP has an automatic/manual reset. Models with automatic/manual reset can have the reset jumpered or can be converted to an unmonitored manual reset by adding a normally open switch in the monitoring loop. Models with monitored manual reset provide checking of the output monitoring circuit.  The outputs include three normally open safety-rated outputs as well as one normally closed auxiliary output. The safety outputs have independent and redundant internal contacts to support the safety function. The auxiliary output is a nonsafety output intended to provide an external signal about the status of the safety outputs.

  • Category 4 per EN 954-1
  • Stop category 0
  • Three safety contacts
  • One auxiliary contact
  • Cross fault monitoring
  • Monitored or automatic reset
  • Removable terminals
  • Light curtain, E-stop or safety gate applications
 MSR125H  

MSR125H/HP

The Allen-Bradley Guardmaster Minotaur MSR125H/HP is a logic unit for monitoring and interfacing two-hand control devices with a safety-related circuit. The MSR125H/HP is for use with mechanical switches and the Rockwell Automation Bulletin 800Z Zero-Force Touch Buttons. The MSR125H/HP has two normally open safety outputs. The safety outputs have independent and redundant internal contacts to support the safety function. The MSR125H/HP requires the two switches to be operated within 0.5 seconds of each other and will only authorize the ON state while both switches are held down. If one of the switches is released, the output goes to the OFF state and the machine cannot be restarted until both buttons are released and then operated simultaneously. The MSR125H/HP conforms to EN 574 Category IIIC, which gives specific requirements for two-hand control units and logic devices.  The MSR125H has fixed terminals and the MSR125HP has removable terminals.

  • Category 4 per EN 954-1
  • Safety category IIIC per EN 574
  • Two-hand control unit
  • Two N.O. safety outputs
  • Fixed or removable terminals
  • 22.5 mm wide housing