Trip Characteristics - Microversatrip Plus™ And Pm - GE WavePro LVPCB Application Manual

Long-Time Protective Functions
• Long-Time Function/Trip Setting (Standard)
The adjustable long-time setting is based on multiples of
the rating plug amp rating. There are 13 possible settings
from 50% to 110% of rating plug amps, in 5% steps. This
setting establishes the trip setting of the breaker which is
the current the breaker will carry continuously without
tripping. Multiplying the long-time setting by the rating
plug value establishes the value of "LT". For example, a
breaker with a 95% long-time setting and 500-amp rating
plug (I n ), would have a 475-amp trip setting value of LT.
(Long-Time current setting (LT) = (0.50 to 1.10) x rating plug (I n ))
Long time function
• Long-Time Delay (Standard)
Long-time delay varies the time it will take the breaker to
trip under sustained overload conditions. It permits the
breaker to ride through momentary predictable overloads
(e.g. motor starting) without tripping. There are 4 time
bands that provide nominal delays from 2.4 to 20 seconds
at 600% of the breakers current setting, or value of LT.
Long time delay
Trip Characteristics — MicroVersaTrip Plus™ and PM™
Instantaneous Function (Standard)
All WavePro™ breakers are available with standard
adjustable instantaneous trip function. The instantaneous
trip point establishes the value of current that will trip
the breaker without intentional time delay. Instantaneous
trip times are 50 milliseconds, or less. Instantaneous trips
are the result of severe overcurrent or short circuit condi-
tions, and damage to the power system is minimized by
immediate tripping. Standard settings are adjustable in
increments of .5 times the rating plug amp value (I n ).
See Table 21.1 for allowable values. Instantaneous trips
may be omitted when the optional short time trip function
is supplied.
Standard Instantaneous function
Short-Time Functions (Optional)
• Short-Time Pickup
The short-time pickup function controls the level of high
current the breaker will withstand for short periods of time
to allow downstream devices to clear faults without tripping
the breaker. Settings are adjustable in increments of 50% of
the breaker trip setting (LT). See Table 21.1 for allowable
values. The short time trip function may be used in conjunc-
tion with or in place of the instantaneous trip function.
Short-time pickup function
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