MicroVersaTrip PM™ Metering and Relaying
(cont.)
25
• Short-time and instantaneous trips: Short-time and instanta-
neous trips share the same trip target. The PICKUP
target is not illuminated, since the time intervals between
pickup and tripping are so short for either function. The
trip target for a short-time or instantaneous trip is “I>>.”
Breaker tripped on short time
Breaker tripped on instantaneous
• Ground-Fault Trip: The trip target for a ground-fault trip
is illumination of the letters “GF.”
Breaker tripped on ground fault
Trip Operations Counter
The trip unit stores the number of trip operations for
long-time, short-time, instantaneous and ground fault.
Up to 256 counts of each trip operation are stored in
memory. Manual reset through the keypad is possible at
any time. The electronic trip operations counter does not
store shunt trip, undervoltage release or protective relay
trips. An optional mechanical operations counter is avail-
able that counts each open-and-close operation of the
main contacts for any reason.
Display showing trip operations counter
Trip Targets - Protective Relays
Trip targets for the enabled protective relays appear in the
status screen when they occur. Symbols used are:
• Undervoltage trip
V<
• Overvoltage trip
V>
• Voltage unbalance
∆
V
• Current unbalance
∆
I
• Power reversal
Programming Trip Units
All MicroVersaTrip Plus™ and MicroVersaTrip PM™ trip
units for WavePro™ breakers use the same programming
keypads. All functions ordered are selectable and displayed.
Programming display and keypad
• Function: Selects the mode of the display (Setup,
Metering or Status).
• Select: Chooses the next item for display. All modes have
a sequential menu that allows the user to step from one
function to the next.
• Battery: Energizes the internal battery circuit and the
LCD.
• Value: Allows changing a setpoint, or changes a metering
display from line-to-line or line-to-neutral, or select
between phases 1, 2 or 3.
• Enter: Stores setpoint in the trip unit’s non-volatile memory.
Trip Targets - Overcurrent And Ground Fault
Trip targets for protective functions use international sym-
bols, and are shown on the LCD when in the Status mode.
• Normal: When all protective circuits are within normal
limits, the term “OK” is visible in the LCD display.
• Long-time trip: The long-time trip display moves through
two transitions. As the current in any phase reaches 95%
of its setpoint, the word “PICKUP” begins to flash. As
current increases, flashing frequency increases, until
100% of the pickup point is reached. At that moment,
PICKUP remains ON, continuously, until the long-time
delay times out. Once the breaker has tripped on long
time, the symbol “I>” appears in the LCD display to
indicate a breaker overload. In addition to this target,
the display indicates the trip status with the word,
“FAULT.” The display shows the type of trip “LT,” the
phase the fault occurred on, and the magnitude of
the fault current. The trip information is displayed
until cleared by the user.
Long-time trip imminent Breaker tripped on long time
