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Macromatic COH05A2BG Over Current Sensing Relay, 0.5-5A, 120V, 4 Sec Delay

Macromatic COH05A2BG Over Current Sensing Relay
Macromatic COH05A2BG 0.5-5A, 120V Over Current Sensing Relay

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Our Price: $88.78
MFG: Macromatic
Weight (lbs): 0.3

Delivery Time: 5-10 Business Days
Product Code: COH05A2BG


The Macromatic COH05A2BG is a current sensing relay. This encapsulated relay has an input voltage of 120V AC. It is designed to monitor for overcurrent situations and has an output of 10A SPDT. It checks AC current, with an adjustable range of 0.5-5A and a trip time delay of 0.5-50 seconds. There is a 4 second sensing time delay on startup. The integrated current transformer provides easy access and greater sensitivity. The encapsulated housing stands up to harsher conditions. Note: Image is an approximation. Actual part may differ.


  • Relay Function- Overcurrent
  • Current Monitor Range- 0.5-5A
  • Time Trip Delay- 0.5-50 seconds
  • Sensing Time Delay on Startup- 4 second
  • Input Voltage- 120V AC
  • Output- 10A SPDT
  • Input Voltage Tolerance- +10/-15% of nominal
  • Load- 2VA
  • Current Sensing- Type: Toroidal, through hole wiring
    Setting Accuracy: Min: +0%, -50%; Max: +10%, -0%
    Maximum Allowable Current: Steady-25A Turns; 150A Inrush for 10 Seconds
    Trip Point Hysteresis: -5%
  • Response Time- Time Delay on Reset (Relay OFF): 100ms
    Reset Time: 400ms
  • Operating Temperature- -28 C to 65 C (-18 F to 149 F)
  • Storage Temperature- -40 C to 85 C (-40 F to 185 F)
  • Output Contacts- 10 Amperes @ 240VAC, General Purpose; 8 Amperes @ 28VDC, Resistive; 1/4HP @ 120/240VAC; B300
  • Life- Mechanical: 10,000,000 Operations, Full Load: 100,000 Operations
  • Mounting- Surface mount with 2 #6 screws
  • Termination- 0.25" male quick-connect terminals
  • Overall Dimensions- 3.5" H x 2.5" W x 1.5" D
  • Approvals- UL & CUL Recognized, CE

Macromatic COH Series Relay Installation Manual

COH05A2BG Overcurrent Sensing Relay with 4 Second Delay

Additional Product Information

The relay starts checking for faults once the input voltage is introduced and after the startup time delay has passed. If an overcurrent fault occurs, the AC current rises above the set Fault Trip Current for longer than the adjusted time delay. The relay energizes after the time delay and de-energizes once the current falls below the reset level. The COH05A2BG has an LED indicator which glows red to show when an overcurrent fault is found. Has pilot duty rating. Process control, monitoring for locked rotor or load loss, and open heater or lamp are all useful applications for this type of relay.