The Macromatic CAH20A2BG is a current sensing relay. This encapsulated relay has an input voltage of 120V AC. It is made to check for over or undercurrent faults and has an output of 10A SPDT. It checks AC current, with an adjustable range of 2-20A and a trip time delay of 0.5-50 seconds. There is a 4 second sensing time delay on startup. The built-in current transformer provides better access and greater sensitivity, as the wire can be looped around multiple times. The encapsulated housing is made for use under harsher conditions. Note: Image is an approximation. Actual part may differ.

Specifications

• Relay Function- Over/undercurrent
• Current Monitor Range- 2-20A
• 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-50A Turns; 300A Inrush for 10 Seconds
  Trip Point Hysteresis: -5% Overcurrent sensing +5% Undercurrent sensing
• 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 two #6 screws
• Termination- 0.25" male quick-connect terminals
• Overall Dimensions- 3.5" Height x 2.5" Width x 1.5" Depth
• Approvals- UL & CUL Recognized

The user selects whether the relay looks for over or under current errors using the switch. The relay starts monitoring for errors once the input voltage is applied and the startup time delay has passed. For an overcurrent fault, the AC current goes over the set Fault Trip Current for longer than the adjusted time delay. The relay energizes after the time delay and remains that way until the current falls below the reset level. In the event of an undercurrent situation, the current drops under the set Fault Trip Current for longer than the time delay. Again, the relay energizes after the time delay and will de-energize once the current rises above the reset level. The CAH20A2BG has an LED indicator which is red to show that a current error has occurred. Has pilot duty rating. Application examples include process control, monitoring for locked rotor or load loss, or open heater or lamp.

Macromatic CAH Series Relay Installation Manual

Macromatic CAH20A2BG Current Sensing Relay