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Figure 61. Location of M5 BCA Standoff
PlusTM

2. Using Torx
T20 and T25 bits, remove the two (2) M4x22mm screws and two (2) M5x18mm screws
securing the AC busbar support for the phase nearest the current sensor being replaced (refer to Figure 62).

Figure 62. Location of M4 and M5 AC Busbar Support Screws
3. Using a Torx PlusTM T20 bit, remove the two (2) M4x22mm screws securing the AC busbar support for the
phase which the current sensor is being replaced (refer to Figure 63).
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April, 2016
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Figure 63. Location of Two (2) M4x22mm Screws
4. Slide the two (2) AC busbar supports under the AC busbar towards the AC lug box end of the chassis
(refer to Figure 64).

Figure 64. Location of AC Busbar Supports
5. Using a Torx

PlusTM

T20 bit, remove the one (1) M4x19mm screw (refer to Figure 65).

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SIL 22­EP­16
April, 2016
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Figure 65. Location of One (1) M4x19mm Screw
6. Remove the non­magnetic spacer located between the bottom of the current sensor and the underside
of the AC busbar (refer to Figure 66).

Figure 66. Non­Magnetic Spacer Location
7. Remove the current sensor by sliding it off the end of the AC busbar (refer to Figure 67).

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April, 2016
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Figure 67. Removal of Current Sensor
CAUTION: Ensure that the screw, spacer and nut have not been left in the DPIM after removing the
Current Sensor (refer to Figure 68).

Figure 68. Current Sensor Fasteners
WARNING: Inspect all reuse components for damage or corrosion, clean or replace any components as
necessary. A vacuum may be used to clean any debris inside the DPIM chassis. Debris or excessive
corrosion can cause isolation faults.

CAUTION: Ensure that the electrostatic discharge wrist strap is properly connected to the DPIM chassis
while using the vacuum.

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SIL 22­EP­16
April, 2016
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Current Sensor Installation
1. Apply one drop of NyoGel® 760G synthetic lubricant to each of the new Current Sensor (P/N 29557482)pins
(refer to Figure 69) and one drop to each of the mating harness terminals.

Figure 69. Applying NyoGel® 760G Synthetic Lubricant to Current Sensor Pins
2. Connect the new harness assembly to the new current sensor ensuring the latch is secure.
NOTE: The wiring harness MUST be replaced along with the current sensor.

3. Install the new current sensor by rotating it down between the AC busbars and then sliding it over the end
of the AC busbar (refer to Figure 70).

Figure 70. Installation of Current Sensor
4. Align the holes in the bracket to the mounting holes in the DPIM chassis and start two (2) M4x16 screws
included in the service kit (refer to Figure 71).
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SIL 22­EP­16
April, 2016
Page 46 of 58

Figure 71. Non­Magnetic Spacer Location
5. Using a pair of snips, cut out the left side of the alignment tool (P/N 29558018) across the top and bottom
of the hole closest to the alignment tabs so the tool will fit around the inverter B encoder board (refer to
Figure 72).

Figure 72. Alignment Tool Cut Location
6. Insert the alignment tool into the plate side of the current sensor so that the tool is against the sensor housing
and sitting on top of the AC busbar (refer to Figure 73). The tool should clear the encoder board.
NOTE: The plate side of the sensor references the side of the sensor with a thin plate that completes the
sensor housing.

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SIL 22­EP­16
April, 2016
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Figure 73. Alignment Tool in Plate Side of Current Sensor
PlusTM

7. Using Torx
T20 and with the alignment tool still installed, torque the two (2) M4x16mm sensor
mounting screws to 1.2­1.5 N∙m (10.6­13.3 lb in.).
8. Remove the alignment tool and verify that the AC busbar is not touching the sensor housing.
9. Route the harness assembly ensuring adequate wire bend radius and secure it to the sensor with a new
zip tie ensuring no relative movement of the harness to the sensor housing. Clip excess zip tie length as
required. (refer to Figure 74).

Figure 74. Harness Routed and Tied to Sensor Housing
10. Label the harness with phase C on the BCA connector end of the harness to assist during reassembly.
11. Install both AC busbar supports by sliding them back in place under the AC busbars.
12. Using Torx PlusTM T20 and T25 bits and Loctite® 242 thread locking compound, install the two (2) M4x22mm
screws and two (2) M5x18mm screws to secure the AC busbar support (refer to Figure 75). Torque the two
(2) M4x22mm screws to 1.2­1.5 N∙m (10.6­13.3 lb in.) and the two (2) M5x18mm screws to 3.1­3.5 N∙m
(27.4­30.9 lb in.).

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SIL 22­EP­16
April, 2016
Page 48 of 58

Figure 75. Location of M4 and M5 AC Busbar Support Screws
13. Using Torx PlusTM T20 and Loctite® 242 thread locking compound, install the two (2) M4x22mm screws
to secure the AC busbar support (refer to Figure 76). Torque the two (2) M4x22mm screws to 1.2­1.5
N∙m (10.6­13.3 lb in.).

Figure 76. Location of Two (2) M4x22mm Screws
14. Apply one drop of Loctite® 242 thread locking compound to the end of the external threads of the M5
BCA standoff. Using an 11mm hex socket, install the one (1) M5 BCA standoff (refer to Figure 77). Torque
the one (1) M5 BCA standoff to 3.1­3.5 N∙m (27.4­30.9 lb in.).

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SIL 22­EP­16
April, 2016
Page 49 of 58

Figure 77. Location of M5 BCA Standoff

Section 7: Installation of the AC Busbar Assembly
1. Carefully install the AC Busbar Assembly into AC Lug Box (refer to Figure 78).
CAUTION: Do not allow the AC Busbar Assembly to strike the HVIL Switch during the installation process.

Figure 78. Installation of AC Busbar Assembly
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SIL 22­EP­16
April, 2016
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2. Install the HVIL switch connector (refer to Figure 79).

Figure 79. HVIL Switch Location

3. Install and finger tighten the three (3) M8 AC lug bolts (refer to Figure 80).

Figure 80. AC Lug Bolts

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SIL 22­EP­16
April, 2016
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4. Apply one drop of Loctite® 425 or 242 thread locking compound to the end of the external threads of the six
(6) M5x22mm screws. Using a Torx PlusTM T25 bit, install the six (6) M5x22mm screws (refer to Figure 81).
Torque the six (6) M5x22mm screws to 3.1­3.5 N∙m (27.4­30.9 lb in.).
NOTE: Install all screws before torquing to ensure that the holes line up.

NOTE: Exercise special care to not pinch any wires when components are installed and screws are
torqued.

Figure 81. Mounting Screw Locations

Section 8: Installation of BCA Card Mounting Shelf
1. Feed all zip ties through the BCA Card Mounting Shelf (refer to Figure 82).

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SIL 22­EP­16
April, 2016
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Figure 82. BCA Card Mounting Shelf Zip Tie Location

2. Place the BCA Mounting Shelf onto the side of DPIM chassis as shown in Figure 83.

Figure 83. BCA Mounting Shelf (GATE Drive Card Cable Connectors Shown Circled)

3. Connect three (3) GATE Drive Card Connectors to three (3) GATE Drive Cards (refer to Figure 84) and
install the cable strain relief caps.

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SIL 22­EP­16
April, 2016
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Figure 84. GATE Drive Card Cable Connector Installation (BCA Card Cable Connector Shown for Clarity)

4. Move BCA Mounting Shelf to its final location. Using a Torx PlusTM T25 bit, install the seven (7) M5x14mm
screws that secure the BCA Mounting Shelf (refer to Figure 85). Torque the seven (7) M5x14mm screws to
3.1­3.5 N∙m (27.4­31.0 lb in.).

Figure 85. BCA Mounting Shelf Fastener Locations

5. Install five (5) wire harness connectors to circuit card surface mount connectors (refer to Figure 86,
Figure 87, and Figure 88).

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SIL 22­EP­16
April, 2016
Page 54 of 58

Figure 86. Wire Harness Connector Installation (4 Locations)

Figure 87. Current A, Current B, and Current C Locations
NOTE: Each current sensor phase (A, B, and C) MUST be plugged into the appropriate connector
(CURR A, CURR B, CURR C).

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SIL 22­EP­16
April, 2016
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CAUTION: Permanent damage to the H 40/50 EPTM Drive Unit or DPIM can occur if the current sensor
harnesses are plugged into the wrong connectors.

Figure 88. Wire Harness Connector Installation

6. Install NEW zip ties as required to retain the wire harnesses (refer to Figure 89).

Figure 89. Zip Tie Locations

Section 9: Installation of HVIL Circuit Card and Main Cover
1. Insert one (1) new zip tie into the new HVIL Circuit Card at the same location as shown in Figure 90.

Copyright © 2016 Allison Transmission, Inc. All Rights Reserved.

SIL 22­EP­16
April, 2016
Page 56 of 58

NOTE: To ease assembly, the new zip tie must be inserted through the hole in the circuit card prior to
installation in the DPIM Housing.

Figure 90. HVIL Circuit Card – Zip Tie Location

2. Install HVIL Circuit Card into the DPIM Housing.
NOTE: Ensure that the wire harnesses and individual wires are NOT pinched under the circuit card
during installation.
3. Connect the three (3) wiring harness connectors at locations shown in Figure 91.

Figure 91. HVIL Circuit Card – Three (3) Harness Connector Locations

4. Using a Torx PlusTM T25 bit, install and finger tighten the ten (10) M5 screws that secure the HVIL Circuit
Card to the DPIM Housing. Torque all M5 screws to 3.1­3.5 N∙m (27­31 lb in). Refer to Figure 92 for
fastener sizes and locations.

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SIL 22­EP­16
April, 2016
Page 57 of 58

Figure 92. HVIL Circuit Card – Fastener Sizes/Locations

5. Install the two (2) wire ring terminals onto the studs at locations shown in Figure 93. Using an 8mm socket,
install four (4) M5 nut/washer assemblies onto the studs as shown in the same figure. Torque the nuts
to 3.1­3.5 N∙m (27­31 lb in).

Figure 93. HVIL Circuit Card – Four (4) Mounting Nut/Washer Locations (M5)

6. Secure wiring with new zip ties and clip excess length as required. Refer to Figure 90 and Figure 94 for
zip tie locations.

Figure 94. HVIL Circuit Card – Two (2) Zip Tie Locations

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SIL 22­EP­16
April, 2016
Page 58 of 58

7. Install new Cover Gasket P/N 29540714, included in Current Sensor and Harness Service Kit. Using a Torx
PlusTM T25 bit, install and finger tighten the twenty­six (26) M5x18mm machine screws that secure the Main
Cover to the DPIM Housing as shown in Figure 95. Torque the screws to 3.1­3.5 N∙m (27­31 lb in).

Figure 95. DPIM Main Cover
NOTE: For additional information refer to H 40/50 EPTM System Service Manual SM3602EN Appendix E.

Copyright © 2016 Allison Transmission, Inc. All Rights Reserved.

NOTE: This illustration is to be used for identifying the name and location
of components within the Dual Power Inverter Module 2 (DPIM2). It is not
intended to be used for disassembly and assembly procedures.

Levels of Assembly
DC Lug
Box

HVIL
Switch

BCA Card
Inverter A

Diode
Inverter A

AC Lug Box
Inverter A

Encoder
Motor A

DC Choke

Gate Drive
Cards
Inverter A

AC Bus Bar
Inverter A

Phase

A

Phase

B

Phase

C

Phase

C

Phase

B

Phase

A

Signal
Interface

HVIL
Switches

DC
Terminal
Block

HVIL
Circuit
Board

BCA Card
Inverter B

Diode
Inverter B

AC Lug Box
Inverter B

Discharge
Resistor

Encoder
Motor B

Level 1
Current
Sensor (x6)

X-Capacitor
(x18)

AC Bus Bar
Inverter B

Level 2
AC Busbar (x6)

DC Busbar

Level 3

Gate Drive
Cards
Inverter B

HVIL Support

AC Terminal
Block (x2)

SKiM Module/IGBT
Cards Inverter A

DC Capacitor SKiM Module/IGBT
(x9)
Cards Inverter B

Level 4

201405