Series: HLM
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The HLMU Series is a universal voltage, encapsulated, 3-phase voltage monitor. It continuously measures the voltage of each of the three phases with microcontroller accuracy and compares the value to preset trip points. It separately senses phase reversal and loss; over, under and unbalanced voltages; and over or under frequency. Protection is assured during periods of large average voltage fluctuations, or when regenerated voltages are present. The unit trips within 200ms when phase loss is detected. Adjustable time delays are included to prevent nuisance tripping and short cycling of sensitive equipment. The isolated, 10A, DPDT relay contacts trip when a phase voltage exceeds the trip limits for the trip delay. Nominal line voltage, voltage unbalance, and time delays are knob adjustable. The phase loss setpoint and the acceptable frequency range are fixed. Both delta and wye systems can be monitored; no connection to neutral is required.

See datasheet for operation details.

Property (Mouseover for details) Value
Input Voltage (V) 200 - 240 Vac; 340 - 420 Vac; 400 - 480 Vac
Input Voltage Maximum (V) 550
Input Type 3-phase delta or WYE with no connection to neutral
Input AC Line Frequency (Hz) 50 / 60 automatically detected; 240 V ac: 50 / 60; 380 V ac: 50; 480 V ac: 60
Input Phase Sequence A; B; C; L1; L2; L3
Output Type Isolated electromechanical relay
Output Form DPDT
Output Load Rating (VA) 10 A resistive @ 240 Vac; 8 A resistive @ 277 Vac; NO-1/4 hp @ 120 Vac; 1/3 hp @ 240 Vac
Reset Time (ms) Automatic
Response Time (ms) Phase loss: ≤200 ms; Phase reversal: ≤200 ms
Restart Delay Range 0.6 - 300 s adjustable; lockout minimum off time
Restart Delay Tolerance (%) ±15%
Trip Delay Type Active On: Over/undervoltage; voltage unbalance; over/under frequency
Trip Delay Range 1-30 s adjustable
Trip Delay Tolerance (%) ±15%
Overvoltage Trip Voltage (%) 109 - 113% of the adjusted line voltage
Overvoltage Reset Voltage (%) ≅-3% of the trip voltage
Undervoltage Trip Voltage 88 - 92% of the adjusted line voltage
Undervoltage Reset Voltage (%) ≅+3% of the trip voltage
Voltage Unbalance Trip Point (%) Adjustable 2 - 10%
Voltage Unbalance Reset (%) ≅-0.7% unbalance
Over/Under Frequency (%) ±4%; Reset ±3%; 50 / 60 Hz
Phase Loss ≥25%
Isolation Voltage (V) ≥2500 Vrms input to output
Surge Protection IEEE C62.41-1991 Level B
Type of Detection Voltage detection with delayed trip and automatic reset
Termination Type Screw terminal connection for up to #12 AWG (3.3 mm²) wire
Mounting Method Surface mount with one #10 (M5 x 0.7) screw
Operating Temperature -40° to 60°C (-40° to 140°F)
Storage Temperature (F/C) -40° to 85°C (-40° to 185°F)
Humidity 95% non-condensing
Dimensions 3 H x 2 W x 1.64 D in. (76.7 x 50.8 x 41.7 mm)
Weight (lbs/g) 0 Kg
Check Stock Yes
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