MicroVersaTrip Plus™ and MicroVersaTrip PM™ Trip Units
Chapter 4. Status Mode
31
Ground-Fault Display
When a ground-fault trip occurs, the display illus-
trated in Figure 62 appears. The fault current is dis-
played in units of
xCT, the breaker CT sensor rating.
Multiply the sensor rating of the breaker by the dis-
played fault current multiplier to obtain the ground-
fault current at trip.
Figure 62. Trip Unit status display for ground-fault trip.
Protective-Relay Fault Display
After a protective-relay trip, the display indicates
FAULT
with a target for the type of relay that initiated
the trip. This is illustrated in Figure 63 for an
overvoltage trip. The targets for the five protective
relays are listed in Table 18.
Figure 63. Trip Unit status display for protective-relay trip.
C
C
C
Co
o
o
od
d
d
deee
e
P
P
P
Prrrro
o
o
otttteee
eccc
cttttiiiivvvveee
e R
R
R
Reee
ellllaa
a
ayyyy
∆
V
Voltage unbalance
∆
I
Current unbalance
V
<
Undervoltage
V
>
Overvoltage
I
I
Power reversal
Table 18. Trip Unit display targets for protective relays.
Shunt Trip and Undervoltage Release Trip
Displays (RMS9D Series Trip Units Only)
When a Power Break ®II breaker trips due to the
Shunt Trip, Shunt Trip with Lockout, or
Undervoltage Release, the display indicates the trip
with a flashing target, as illustrated in Figure 64. The
indications
ST
and
UVR
appear for Shunt Trip and
Undervoltage Release trips, respectively. Note that
the
FAULT
segment does not display, since the trip
originated external to the breaker and may not
represent a true fault condition.
Figure 64. Trip Unit status display for Undervoltage Release
trip.
Clearing the Trip Information
Since trip information is stored in nonvolatile mem-
ory, the Trip Unit continues displaying the trip
information until it is manually cleared or a new trip
occurs. After the trip information has been recorded
or reviewed, it can be cleared with the keypad. With
the Trip Unit in Status mode, hold down the
VALUE
key and press the
SELECT
key. The trip information is
then cleared and the display reverts to
STATUS OK
, as
in Figure 56.
Trip Operations Counter Display
Trip operations counters record the total number of
overcurrent trips. To review any of the trip opera-
tions counters while in Status mode, press the
SELECT
key until the desired count appears. Figure 65
illustrates a typical trip operations counter display.
This example indicates that there have been three
long-time trips on this breaker since the counter was
last reset.
