Trip Units — MicroVersaTrip PM™
23
+24 Vdc Input
MicroVersaTrip PM™ trip units require an ex24 Vdc
auxiliary power supply to furnish power to the communica-
tion network. In addition, this power supply energizes the
LCD display, so that low current values, voltage values and
trip targets are displayed without use of the internal batter-
ies. However, batteries are supplied with MicroVersaTrip
PM trip units for cold set-ups and viewing targets in the
event the +24 Vdc power supply is interrupted. A 24
Vdc power supply can supply the power requirements of up
to 30 MicroVersaTrip PM trip units.
This power supply may also be used with MicroVersaTrip
Plus trip units. This allows low current values and trip tar-
gets to be displayed without the use of the trip unit internal
batteries, similar to the operation of the MicroVersaTrip PM
trip unit.
Communications Output
The communications network uses a pair of shielded,
twisted wires to connect individual devices to the POWER
LEADER™ system. All communication network wiring
within the breaker is prewired to dedicated secondary
terminals.
Rating
Plug
Optional Neutral Current
Communications Link
Zone Selective Interlock
A B C N
Phases
Input/Output
(Optional)
A B C N
Phases
Trip Unit Keypad
Currents
Phase
Breaker Mounted
Current Sensors
Voltage Transformers with
120Vac Secondaries
Liquid
Crystal
Display
(Microswitch)
-Power Reversal
Auxiliary Contact
24Vdc Power Supply
Fault
Trip Unit
Protective Relays
-Overvoltage
-Undervoltage
-Current Unbalance
-Voltage Unbalance
Va
Vb
Vc
A/D Con
v
e
rter
Fault
T
rip Logic
MicroVersaTrip PM
Bell Alarm
Lockout
with or w/o
T
rip Actuator
Block diagram of MicroVersaTrip PM trip unit