GE Conversion Kits are designed for upgrading
existing GE low-voltage power circuit breakers, rather
than replacing the entire breaker. The Conversion Kits
include ProTrip™ Trip Units, the latest technological
advance in GE trip systems.
ProTrip Conversion Kits are designed and tested to
conform to ANSI Standard C37.59, allowing the
retrofitter to properly install the kit and acceptance
test the breaker.
This publication covers installation of ProTrip Conversion Kits on GE types AK-1-15 and AK-1-25 lowvoltage power circuit breakers. Each Conversion Kit
contains all the components needed to convert from
an existing GE trip system.
ProTrip™ Conversion Kit
For GE Types AK-1-15 and AK-1-25
Low-Voltage Power Circuit Breakers
TABLE OF CONTENTS
SECTION 1. GENERAL INFORMATION........................................................................................................... 5
SECTION 2. BEFORE INSTALLATION.............................................................................................................. 5
5. Bottom bus installation. .................................................................................................................................7
7. Top bus connection ........................................................................................................................................8
10. Installing the flux shifter assembly. ............................................................................................................10
11. Trip unit support bracket installed. .............................................................................................................10
12. Trip unit attached to its mounting plate. ....................................................................................................11
13. Harness connector attached to the trip unit. ..............................................................................................11
14. Trip unit mounted on the breaker................................................................................................................11
18. Cabling diagram for PtoTrip™ trip units with ground fault on four-wire loads......................................16
4
SECTION 1. GENERAL INFORMATION
SECTION 2. BEFORE INSTALLATION
GE Conversion Kit installation is straightforward, but
does require careful workmanship and attention to
these instructions. Familiarity with the breaker is
highly desirable. Then general approach is to first
remove the existing trip devices from the breaker,
then install the ProTrip components. Following this
procedure, the converted breaker is performance
tested before it is returned to service.
The majority of trip unit kit installations do not
require any customized assembly work. However,
some installations may involve unusual mounting
conditions or accessory combinations that require
minor modifications and/or relocation of components. In most instances, this supplementary work
can be done on site.
NOTE:
patible with the conversion kit.
In preparation for the conversion, the installer should
verify that the appropriate current sensors and trip
unit have been furnished. Whenever a ProTrip kit is
installed on a breaker with a four-wire system, an
associated neutral sensor (CT) is required for
separate mounting in the equipment. Ensure that
retrofitted breakers are applied within their shortcircuit ratings.
Note that all ProTrip trip units supplied with conversion kits are equipped with long-time, short-time,
instantaneous, and defeatable ground fault (LSIGX)
trip functions. The installer should be aware of how
these functions will affect his application before
installing the conversion kit.
As a service-related consideration, the installation of
a ProTrip kit provides an excellent opportunity to
perform normal maintenance on the breaker, particularly when the front and back frames are separated. Such procedures are described in the installation and maintenance manuals supplied with the
breaker and equipment.
The bell alarm accessory may not be com-
Before starting any work, turn off and lock out all
power sources leading to the breaker, both primary
and secondary. Remove the breaker to a clean, welllighted work area.
WARNING:
high-speed, stored-energy spring operating
mechanisms. The breakers and their enclosures
contain interlocks and safety features intended to
provide safe, proper operating sequences. For
maximum personnel protection during installation,
operation, and maintenance of these breakers, the
following procedures must be followed. Failure to
follow these procedures may result in personal
injury or property damage.
• Only qualified persons, as defined in the
National Electrical Code, who are familiar with
the installation and maintenance of low-voltage
power circuit breakers and switchgear assemblies, should perform any work on these breakers.
• Completely read and understand all instructions
before attempting any breaker installation,
operation, maintenance, or modification.
• Turn off and lock out the power source feeding
the breaker before attempting any installation,
maintenance, or modification. Follow all lock-out
and tag-out rules of the National Electrical Code
and all other applicable codes.
• Do not work on a closed breaker or a breaker
with the closing springs charged. Trip an
breaker and be sure the stored-energy springs
are discharged, thus removing the possibility
that the breaker may trip
springs discharge and cause injury.
• Trip the breaker
to a well-lighted work area before beginning
work.
• Do not perform any maintenance that includes
breaker charging, closing, tripping, or any other
function that could cause significant movement
of a draw-out breaker while it is on the draw-out
extension rails.
• Do not leave the breaker in an intermediate
position in the switchgear compartment. Always
leave it in the
DISCONNECTED position. Failure to do so could
lead to improper positioning of the breaker and
flashback.
Low-voltage power circuit breakers use
OPEN
OPEN or the closing
OPEN, then remove the breaker
CONNECTED, TEST, or
5
SECTION 3. DISASSEMBLING THE
BREAKER
GE Type AK-1 breakers need not have their front and
back frames separated for installation of the
conversion kit. The procedure is to remove the old
electromechanical trip units, then install the kit.
First, remove the breaker from its compartment and
place it on a clean, well-lighted workbench in an
upright position, so that both the front and back are
easily accessible.
Component Removal
1. Remove and save the load terminal primary disconnect fingers on all draw-out breakers. They
are held in place with a
Figure 1.
2. Remove and discard the two screws on each side
of the EC trip units, shown in Figure 2, that hold
the covers in place.
3. Remove and discard the Philips-head screw
above each EC trip unit. It may be necessary to
remove the left and right trip paddles. The trip
paddles may be discarded.
4. Remove and discard the two
bolts holding the trip unit coils to the breaker
frame.
5. Remove and discard the three electromechanical
trip units. The disassembled breaker is shown in
Figure 4.
1
/4-20 bolt, as shown in
5
/16-inch Allen-head
Figure 2. EC trip unit removal.
Figure 3. Removing the trip unit coil connections.
Figure 1. Draw-out primary disconnect fingers.
Figure 4. Disassembled AK-1-25 breaker.
6
SECTION 4. INSTALLING THE
CONVERSION KIT
Installing the Current Sensors (CTs)
1. Place the bottom copper bus in the breaker frame
and insert the
lock washer, as shown in Figure 5.
2. Insert the
washer through the electrical contact hole in the
top of the bus, as shown in Figure 5.
3. Remove the
back of the breaker above the load terminal that
aligns with the hole in the copper bus. On AK-115 breakers, it is the right screw; on AK-1-25
breakers, it is the left screw. Replace the screw
with the
4. Use the
on the screw inserted in step 3 to fasten the bus,
as shown in Figure 5.
5. Place the CT, insulating barrier, and top copper
bus over the copper CT post. Secure the bus with
5
/16-18 x 1" bolt, flat washer, and lock washer
the
provided, as shown in Figure 6.
1
/4-20 x 7/8" screw with a flat and
3
/8-20 x 11/4" bolt with a flat and lock
1
/4-20 Philips-head screw from the
1
/4-20 x 15/8" screw provided.
1
/4-20 nut, flat washer, and lock washer
Figure 5. Bottom bus installation.
Figure 6. CT assembly.
7
6. Insert the
3
/8-16 x 21/4" bolt, lock washer, and flat
washer provided through the top copper bus into
the contact arm, as shown in Figure 7.
7. Tighten the
5
/16-18 bolts CT bolts, placed in step
5, to 100 in-lb, as shown in Figure 8.
8. Tighten the two
3
/8-16 bolts inserted in steps 2
and 6 to 200 in-lb.
WARNING:
Steps 7 and 8 provide critical electrical
integrity connections. The designated bolts must be
correctly tightened for proper operation. Failure to
tighten these bolts properly will cause a breaker
failure, resulting in property damage and/or
personal injury.
Figure 7. Top bus connection.
Figure 8. CT assembly torque.
8
Mounting the Trip Paddle
Install the new trip paddle on the right end of the
common trip bar over the draw-out interlock, as
5
shown in Figure 9. Use the two 10-32 x
and lock washers that hold the interlock lever in
place.
/8" screws
Figure 9. Trip paddle installation.
9
Installing the Flux Shifter Assembly
1. Remove the two 1/4-20 nuts or bolts and washers
on the right side of the mechanism that hold the
mechanism together. The flux shifter will be held
in place with the existing studs or bolts.
2. Install the flux shifter assembly onto the existing
studs as shown in Figure 10. Use the
or bolt and lock washer to secure the top of the
bracket to the side of the handle mechanism and
the lock washer and special fastener to secure the
bottom.
1
/4-20 nuts
NOTE:
Figure 10 shows the handle removed for
clarity. It is not necessary to remove the handle
during installation.
3. Place the two 1/2" spacers over the studs on the
flux shifter mounting plate, as shown in Figure
10. Place the two mounting holes in the trip unit
support bracket over the studs on the top of the
flux shifter bracket, as shown in Figure 11. Secure
1
with the
/4-20 nuts, flat washers, and lock
washers provided.
NOTE:
The right-corner enclosure bolt may have to
be shortened if it interferes with the bracket or the
trip unit.
Figure 10. Installing the flux shifter assembly.
Trip Unit
Support
Bracket
10
Figure 11. Trip unit support bracket installed.
Installing the Trip Unit
1. Place a lock washer and flat washer over each of
the three
through the mounting holes on the trip unit
mounting plate. From the rear of the plate, place
a flat washer, spacer, and O-ring over the screws,
as shown in Figure 12.
2. Remove the large screw from the rear of the trip
unit. Place the trip unit in position on the mounting plate, with the 50-pin connector aligned with
the opening in the plate. Secure with the large
screw, as shown in Figure 12.
3. Insert the 50-pin female connector on the wiring
harness into the trip unit connector through the
rear of the mounting plate. Secure to the mounting plate with the two small screws provided, as
shown in Figure 13.
4. Place the trip unit and mounting plate in position
on the support bracket mounted to the breaker.
Secure with the screws in the mounting plate into
the tapped holes in the bracket, as shown in
Figure 14.
1
/4-20 x 13/8" screws provided and insert
Figure 13. Harness connector attached to the trip unit.
Figure 12. Trip unit attached to its mounting plate.
Figure 14. Trip unit mounted on the breaker.
11
Adjusting the Flux Shifter
With the breaker in the CLOSED position, the gap
between the adjustment screw and the trip paddle
1
should be
OPEN the breaker to adjust the screw with a 1/4-inch
wrench.
WARNING:
closed breaker.
while adjusting the flux shifter.
Optional Test
closing the breaker and applying a 9 Vdc power
source to the flux shifter leads (the red wire is positive). The breaker should trip.
/16 inch, as shown in Figure 15. For safety,
Be extremely careful when working on a
Do not
– The flux shifter may be tested by
reach into the mechanism
Connecting the Trip Unit Wiring Harness
1. Join the four-pin connector on the trip unit harness to the four-pin connector on the flux shifter.
2. Connect the harness leads to the screw terminals
on each CT, as shown in Figure 16. The black wire
(tap) connects to the left terminal and the white
wire (common) to the right terminal.
3. Use the wire ties provided to tie the harness back
against the frame. The harness should be tied to
the holes in the fiber barriers at each CT. Ensure
that the wiring will not interfere with any moving
parts.
Figure 15. Flux shifter adjustment.
Figure 16. Wiring harness installation.
12
Configuring the Trip Unit
See DEH-40034 for detailed instructions for setting up
ProTrip trip units.
SECTION 5. FOUR-WIRE GROUND
FAULT OPTION
The ground fault option for four-wire installations
requires the installation of an additional current
sensor on the neutral bus in the equipment. The
sensor is connected to the trip unit through the
connector provided in the wiring harness.
1. Mount the neutral sensor on the outgoing neutral
lead, normally in the bus or cable compartment in
the equipment. Figure 17 shows the outline of the
neutral sensor.
2. Connect the neutral sensor wire harness to the
correct taps on the sensor. To maintain the same
polarity as the phase sensors, connect the white
wire to the common terminal, black to the tap.
3. Route the wires through the equipment and con-
nect to the two-pin connector on the trip unit wiring harness. The wires should be tied to the
breaker frame in an easily accessible location. It
may be located with the communication harness.
Figure 17. Neutral sensor outline.
13
SECTION 6. TESTING AND TROUBLESHOOTING
WARNING:
sors or adjust the trip unit settings while the breaker
is carrying current. Failure to adhere to these
instructions will void all warranties.
Testing
Before installing a converted breaker back into
service, perform the following steps:
1. Verify that the trip unit is securely installed by
performing a continuity test on the CT wiring and
the trip unit.
a. Disconnect the black CT wires at each phase
b. Check for continuity with a continuity tester or
c. Repeat this continuity test for the white leads
d. Measure the resistance across each phase
e. Reconnect the black CT leads to all of the
Do not change taps on the current sen-
sensor.
VOM from the white lead of the phase A CT to
the white lead of the phase B CT.
of the phase A and phase C CTs.
sensor and compare the values measured to
the values listed in Table 1.
phase sensors. Ensure that this is done before
continuing with performance testing of the
breaker.
harness, flux shifter, and trip unit as a complete
system.
a. A high-current, low-voltage power supply
should be connected across each line and load
terminal to simulate an overcurrent fault.
b. Set the long-time trip at 0.5 to minimize the
breaker stress.
c. When ground fault is installed, the test can be
performed by wiring two adjacent poles in
series or by using the GE Digital Test Kit, cat.
no. TVRMS2. This will prevent the breaker
from tripping because of an unbalanced current flow.
CAUTION:
TVTS1 or TVRMS on this trip unit.
Do not attempt to use GE Test Kit cat. no.
Trouble-Shooting
When malfunctioning is suspected, first examine the
breaker and its power system for abnormal conditions such as the following:
• The breaker is not tripping in response to overcurrent conditions or incipient ground faults.
• The breaker is remaining in a trip-free state
because of mechanical interference along its trip
shaft.
• The shunt trip (if present) is activating improperly.
CAUTION:
described in Step 1 and before performance testing
of the converted breaker, each phase of the breaker
should be primary injected with a current level of
about 10%, but no more than 20%, of the CT rating.
WARNING:
tested by primary injection with a sufficiently high
test current with a loose or open circuit between the
CTs and the trip unit, damage will occur to the trip
unit, wire harness, 50-pin trip unit connector, and
CTs. Failure to adhere to these instructions will void
all warranties.
2. Check the insulation on the primary circuit with a
1,000-volt Meggar.
3. Measure the resistance across the line and load
terminals for each phase using a micro-ohmmeter or millivolt tester. If the resistance differs
considerably from phase to phase, the electrical
connections may not be properly tightened or it
could also indicate improper contact wipe.
4. To verify that the breaker has been properly retrofitted, perform a primary injection test on each
phase. This test will check the CTs, bus, wiring
In addition to the continuity test
If the converted breaker is energized or
Nuisance Tripping on Ground Fault-Equipped
Breakers
When nuisance tripping occurs on breakers equipped
with ground fault trip, a probable cause is the
existence of a false ground signal. Each phase sensor
is connected to summing circuitry in the trip unit.
Under no-fault conditions on three-wire load circuits,
the currents add to zero and no ground signal is
developed. This current sum is zero only if all three
sensors have the same electrical characteristics. If
one sensor differs from the others (such as by a
different rating or wrong tap setting), the circuitry can
produce an output sufficient to trip the breaker.
Similarly, a discontinuity between any sensor and the
trip unit can cause a false trip signal.
The sensors and their connections should be closely
examined if nuisance tripping is encountered on any
breaker whose ProTrip trip unit has previously
demonstrated satisfactory performance. After disconnecting the breaker from all power sources, perform the following procedure:
1. Check that all phase sensors are the same type
(current range).
2. Verify that the tap settings on all three phase sensors are identical.
14
3. Verify that the wiring harness connections to the
sensors have the proper polarity (white lead to
common, black lead to tap), as shown in the
cabling diagram in Figure 18.
4. On ground fault breakers serving four-wire loads,
check that the neutral sensor is properly connected, as indicated in Figure 18. In particular,
check the following:
a. Verify that the neutral sensor has the same rat-
ing and tap setting as the phase sensors.
b. Verify continuity between the neutral sensor
and its equipment-mounted secondary disconnect block. Also check for continuity from the
breaker-mounted neutral secondary disconnect
block through to the trip unit wiring harness
connector.
c. If the breaker’s lower studs connect to the
power source, then the neutral sensor must
have its load end connected to the source.
d. Verify that the neutral conductor is carrying
only the neutral current associated with the
breaker’s load current (the neutral is not shared
with other loads).
5. If the preceding steps fail to identify the problem,
then measure the sensor resistances. The appropriate values are listed in Table 1. Since the phase
and neutral sensors are electrically identical, their
resistances should agree closely.
Breaker CT Rating, A Resistance, ohms
AK-1-15
AK-1-25
150
225
225
600
9–12
14–18
14–18
40–50
Table 1. CT resistance values.
15
Figure 18. Cabling diagram for ProTrip™ trip units with ground fault on four-wire loads.
16
These instructions do not cover all details or variations in equipment nor do they provide for every possible
contingency that may be met in connection with installation, operation, or maintenance. Should further
information be desired or should particular problems arise that are not covered sufficiently for the purchaser’s
purposes, the matter should be referred to the GE Company.
GE Industrial Systems
General Electric Company
41 Woodford Ave., Plainville, CT 06062