GE WavePro LVPCB, Инструкция по применению

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Trip Units — MicroVersaTrip Plus™ and PM™
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The Enhanced MicroVersaTrip Plus™ And
MicroVersaTrip PM ™ Trip Unit Systems
The enhanced MicroVersaTrip Plus and MicroVersaTrip PM
trip unit systems for WavePro™ low voltage power circuit
breakers consist of the trip unit, the trip actuator, current
sensors and rating plug. The term “trip unit system” applies
to the combination of these four components which form
the circuit breaker solid-state tripping system.
MicroVersaTrip Plus trip units provide a complete range of
standard and optional overcurrent and ground-fault protec-
tive functions. MicroVersaTrip PM trip units add advanced
metering, communications and protective relaying func-
tions. MicroVersaTrip PM trip units operate with the GE
POWER LEADER™ Power Management System.
Components of MicroVersaTrip Plus unit system
True RMS Sensing
Enhanced MicroVersaTrip Plus and MicroVersaTrip PM trip
units continue to use GE’s proven technique of measuring
true rms currents (and voltages for MicroVersaTrip PM trip
units) of both sinusoidal and harmonically distorted wave-
forms. The sampling rate of 64 times per cycle per phase
allows precise calculations of true rms current and wave-
form measurements up to the 31st harmonic to achieve
accuracies of 99%. GE’s true rms sensing avoids potential
underprotection or overprotection problems associated with
peak-sensing tripping systems.
Enhancements To MicroVersaTrip Plus And MicroVersaTrip PM
Trip Units
Enhancements include several functions that simplify pro-
gramming and make fault displays easier to read and inter-
pret.
Batteries
Replaceable, long-life lithium batteries provide program-
ming and display power to the trip unit’s LCD on com-
mand. With the breaker disconnected from the source and
load, the trip unit can be removed from the breaker and all
setpoints can be defined at a technician’s desk. Caution: the
batteries are automatically shut off when no programming
operation or display request is called for within 30 seconds
after the last key is pressed. The batteries also enable the
user to read fault displays on an open breaker.
Batteries are not required to energize the trip unit display as
long as a small amount of current (20% of current sensor
rating) is flowing through the circuit breaker. The displays
of installed MicroVersaTrip PM trip units are visible at all
times due to an external 24Vdc input to the trip unit.
The batteries are not required to maintain programmed set-
tings, or to store trip information. They simply provide a
local power source to energize the trip unit when no other
source of power is available. All setpoints, time delays and
other programming functions are stored in non-volatile
memory within the trip unit’s microprocessor.
Batteries have a two year life under normal use and are user-
replaceable.
LCD
The LCD (Liquid Crystal Display) has increased contrast to
improve legibility in poor lighting conditions. International
display symbols are used for various programming functions
(e.g., “I>>” for short circuit and “I>” for overload).
Trip Operations Counter
The enhanced MicroVersaTrip Plus and MicroVersaTrip PM
trip units also store and display the total number of trips
due to long time overloads, short time and instantaneous
short circuit, and ground faults. Each display stores up to
256 operations per trip category before resetting to zero.
Each counter can be individually reset through the keypad.