The Macromatic CAH05A8BF is a current sensing relay. This encapsulated relay has an input voltage of 24V AC/DC. It is made to check for either over or undercurrent situations and has an output of 10A SPDT. It monitors AC current, with an adjustable range of 0.5-5A and a trip time delay of 0.5-50 seconds. There is a 3 second sensing time delay on startup. The built-in current transformer promotes easy access and greater sensitivity. The encapsulated housing makes it ideal for use in harsh environments. Note: Image is an approximation. Actual part may differ.

Specifications

• Relay Function- Over/undercurrent
• Current Monitor Range- 0.5-5A
• Time Trip Delay- 0.5-50 seconds
• Sensing Time Delay on Startup- 3 seconds
• Input Voltage- 24V AC/DC
• 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% 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

It is possible to select whether the relay monitors for over or under current situations. The relay starts checking for faults once the input voltage is introduced and the startup time delay has passed. For an overcurrent situation, it occurs when the AC current goes above the set Fault Trip Current for longer than the adjusted time delay. The relay energizes after the time delay and stays energized until the current goes below the reset level. For an undercurrent fault, the current needs to go 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 goes over the reset level. The CAH05A8BF includes an LED which glows red to show when a fault is detected. Has pilot duty rating. It is useful in applications such as process control, checking for locked rotor or load loss, or open heater or lamp.

Macromatic CAH Series Relay Installation Manual

CAH05A8BF Macromatic 24V Encapsulated Current Sensing Relay