The Macromatic CUH05A8BH is a current sensing relay. This encapsulated relay has an input voltage of 24V AC/DC. It is designed to monitor for under current faults 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 5 second sensing time delay on startup. The built-in current transformer promotes easy access and greater sensitivity. The encapsulated casing is ideal for harsh environments. Note: Image is an approximation. Actual part may differ.

Specifications

• Relay Function- Under Current
• Current Monitor Range- 0.5-5 Amps
• Time Trip Delay- 0.5-50 seconds
• Sensing Time Delay on Startup- 5 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%
• 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

When the input voltage is introduced, and after the 5 second start-up delay, the relay then starts monitoring for faults. For an undercurrent situation, the current needs to go under the set Fault Trip Current for longer than the time delay. The relay energizes after the time delay and will de-energize once the current goes over the reset level. The CUH05A8BH has an LED indicator which glows red to show if an undercurrent fault is detected. Has pilot duty rating. Applications such as process control, monitoring for locked rotor or load loss, and open heater or lamp are all suited for this type of relay.

Macromatic CUH Series Relay Installation Manual

Under Current Sensing Relay with 5 Second Startup Delay CUH05A8BH