Designed to replace the conventional thermal bimetal protection device this electronic version is far more accurate and longer lasting than anything used before.  Newelec’s LA Series is designed to be user-friendly with only one setting and includes an integrated current transformer that allows conductor cables to run through it carrying up to 250A.

The relay has control panel mounded fault indication LEDs that are latched for overload, phase loss and unbalanced load trips.  Whenever the thermal capacity of the motor has not recovered to an acceptable value, attempts at resetting the relay will be met with a blinking fault LED that will subsequently automatically extinguish on completion of the cooling off period.

The factory set thermal curve class is 15 seconds and the unbalanced loads detection threshold is set at a maximum of 20% between phases.  When used in conjunction with a mechanically and electrically interlocked cubicle door, the trip indication will be temporarily lost until the supply power is restored to the relay.

Alternatively, the relay may be fitted with a permanent Nicad battery that keeps all LEDs functional when there is a loss of auxiliary power supply.

Protection Features:

  • Thermal Overload Protection
  • Locked Rotor Protection
  • Running Stall / Jam Protection
  • Unbalanced Current / Single Phasing
  • Fail-safe Trip Relay Configuration
  • Stable Operation with VSD / Soft Starters
  • No additional CTs up to 250 Amps
  • Descriptive Fault Indication LEDs
  • Indication and Trip Test Facility

Typical Applications

    • Pump motor
    • Thermal motor protection within Class 5 Hot curve
    • Compressor motors with cyclic loading

Tel. +27 12 327-1729

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