MicroVersaTrip Plus™ and MicroVersaTrip PM™ Trip Units
Chapter 1. Introduction
7
Power Requirements
A small amount of power is necessary to energize the
liquid crystal display (LCD) during setup, for
viewing breaker status, and for metering displays.
MicroVersaTrip PM Trip Units require ex24
Vdc control power for proper operation. The four
sources of such power are the following:
•
Flow of current -- Breaker current sensors
provide sufficient power to energize the LCD
when at least 20% of the sensor’s ampere rating
is flowing.
• +
24 Vdc control power – Breakers with
MicroVersaTrip PM Trip Units are supplied
with ex24 Vdc power that, whenever
present, energizes the LCD. Some breaker
models that are configured for MicroVersaTrip
Plus Trip Units may be optionally equipped to
accept an ex24 Vdc supply.
•
Internal Battery Power – The Trip Unit has an
internal battery that powers the unit temporarily
when the
BATTERY
key on the display is pressed.
Battery power automatically turns off 30 seconds
after the last keypad press. The battery power
supply is disabled when any current is sensed
through the current sensors.
•
MicroVersaTrip Portable Power Pack -- The
MicroVersaTrip Portable Power Pack contains a
dc power source and a jack. The LCD is ener-
gized when the jack is plugged into the rating
plug test receptacle.
•
Power Break® II Undervoltage Release and
Shunt Trip Accessories – When energized, these
accessories 24 Vdc power to the Trip
Unit.
1-7 Trip Unit Information
Trip Unit Label Information
Following are descriptions of the various labels on
the front of the Trip Unit, as illustrated in Figure 5.
•
Extreme top -- circuit breaker series and/or
serial number of the breaker, unless it is a
replacement unit.
•
Upper-left corner – Trip Unit-series serial
number, such as
RMS9C000143
.
Figure 5. Labels on front of Trip Unit.
•
Upper-right corner -- Trip Unit date of manufac-
ture code, such as
E439=
.
•
Lower-left corner -- catalog number of the Trip
Unit, such as
B220LSIGPM
.
•
Lower-right corner-- sensor rating of the Trip
Unit, such as
SENSOR (CT) = 2000A
.
•
Below battery cover -- indicates whether the unit
is MicroVersaTrip Plus or MicroVersaTrip PM.
There are several other labels on the Trip Unit that
are not generally visible when the unit is plugged
into a breaker:
•
Under battery cover – yellow caution label.
•
Side of unit -- bar-coded catalog number and
bar-coded serial number of unit.
•
Rear of unit -- yellow caution label. RMS9D-series
Trip Units also have a label to indicate which
accessory functions are activated by the rear-
panel DIP switches.
Function Keys
The Trip Unit has four function keys and a battery
enable key. These are marked
FUNCTION
,
SELECT
,
VALUE
,
ENTER
, and
BATTERY
, as illustrated in Figure
6. All setup, status, and metering functions and
displays are accessed through these keys. As each set
