GE AKR-30 Series Maintenance Manual page 260

SECTIO N 1 4-MicroVersaTrip® Plus and M icroVersaTrip® PM Trip U nits
1 4.8 TRIP U NIT FUNCTIONS
MicroVersaTrip® Plus and MicroVersaTrip® P M trip units
have specific standard and optional functions. All trip
units share a series of interchangeable rating plugs. The
standard functions for both types of trip unit are as
follows:
•
Protection
- Long-time protection
- Instantaneous protection
•
Status
- Trip target
•
M etering display
- Phase current (selectable among phases)
The optional functions avai lable on both types of trip
unit are as follows:
•
Adjustable protection
- Switchable instantaneous and g round-fault
protection
- High-range (fixed) instantaneous overcurrent
protection
- Short-time protection, with or without 1 2T
82
- Grou nd-fault protection, with or without 1 2T
- Zone-selective interlock, with g round fault only
or with both g round fault and short time
Additional optional functions avai lable only with P M
style trip un its are as follows. P M style trip u nits requ i re
the presence of external control power.
•
Configurations
- Communication and metering
- Communication and p rotective relaying
- Communication, metering, and protective relaying
•
Metering and protective-relaying functions
- Voltage
- Energy (kWh/MWh}
- Real power (kW/MW)
- Total power (kV AIM VA)
- Frequency (Hz)
- Protective relays (undervoltage, overvoltage,
voltage unbalance, current unbalance, and
power reversal}