CHAPTER 3: MOTOR PR OTECTION
EP OS MOTOR MANAGEMENT SY STEM – INSTRUCTION MANUAL
3.19
3.2 Phase loss and current unbalance
The Current Unbalance is detected whenever the minimum of the three phase currents is less than 70% of the
maximum phase current (RMS value).
The Phase Loss is detected whenever the minimum of the three phase currents is less than 40% of the maximum
phase current (RMS value).
NOTE:
The phase unbalance and phase loss protections are only available on 3-phase systems. For non-ATEX
certification systems, the delay time can be set from 1 to 15 seconds. For ATEX certified units, phase loss and
unbalance are enabled, with faults occurring immediately. Phase loss cannot be modified to generate a warning in
case of ATEX.
Phase unbalance and phase loss time delay are set in WinESG parameterization/device settings panel shown in the
illustration below or Modbus function code 06 register 56.
Phase unbalance and phase loss can be enabled or disabled, set as a warning or failure and requiring an auto or
manual reset after a failure, in WinESG parameterization/alarms panel shown in illustration below or Modbus
function code 6 registers 114 (enable/disable), 64 (warning/failure), and 63 (auto/manual reset).
