The Macromatic CAH05A1AD is a current sensing relay. This encapsulated relay has an input voltage of 240V. It is designed to monitor for 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 0.15-7 seconds. It has a 1 second sensing delay on startup. The integrated current transformer provides easy access and greater sensitivity. The encapsulated housing is intended for use under harsh conditions. Note: Image is an approximation. Actual part may differ.

Specifications

• Relay Function- Over/undercurrent
• Current Monitor Range- 0.5-5A
• Time Trip Delay- 0.15-7 seconds
• Sensing Time Delay on Startup- 1 second
• Input Voltage- 240V 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% 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 2 #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 choose whether the relay monitors for over or under current conditions with the selector switch. The relay starts checking for possible faults once the input voltage is introduced and the startup sensing delay has passed. For an overcurrent situation, this happens 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 situation, 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 CAH05A1AD has an LED indicator which glows red to show when a fault is detected. Has pilot duty rating. It is ideal in applications such as process control, monitoring for locked rotor or load loss, or open heater or lamp.

Macromatic CAH Series Relay Installation Manual

CAH05A1AD Macromatic Over/Under Current Sensing Relay