Electrical Best Practices Page |1

Best Practices Electrical 2015

Contents Scope ........................................................................................................................................................................................................................... 9

Common Electrical Problems ...................................................................................................................................................................................... 10

GENERAL INFORMATION ........................................................................................................................................................................................ 10

FAILURE MODES ..................................................................................................................................................................................................... 10

Short Circuit ........................................................................................................................................................................................................ 10

Open Circuit........................................................................................................................................................................................................ 10

Intermittent Circuit ............................................................................................................................................................................................. 11

Sources of Electrical Problems ............................................................................................................................................................................ 12

OEM and Auxiliary Battery Guidelines ........................................................................................................................................................................ 17

OEM BATTERY GUIDELINES ..................................................................................................................................................................................... 17

General Information ........................................................................................................................................................................................... 17

Discharge Prevention .......................................................................................................................................................................................... 18

Charging Procedures ........................................................................................................................................................................................... 19

OEM BATTERY RELOCATION GUIDELINES ............................................................................................................................................................ 20

Location .............................................................................................................................................................................................................. 20

Vibration: ........................................................................................................................................................................................................... 20

Accessibility ........................................................................................................................................................................................................ 20

Tilt Angles ........................................................................................................................................................................................................... 21

Temperature ...................................................................................................................................................................................................... 21

AUXILIARY BATTERY GUIDELINES ............................................................................................................................................................................ 21

General Information ........................................................................................................................................................................................... 21

Location .............................................................................................................................................................................................................. 21

Venting ............................................................................................................................................................................................................... 22

Mounting and Fastening ..................................................................................................................................................................................... 22

Connecting and Grounding ................................................................................................................................................................................. 22

Electrical Best Practices Page |2

Best Practices Electrical 2015

Cable Sizing......................................................................................................................................................................................................... 22

BATTERY DISCHARGE LIMITER GUIDELINES ......................................................................................................................................................... 23

Electrical System Interfacing New Circuit Guidelines ................................................................................................................................................ 25

NEW CIRCUIT GUIDELINES .................................................................................................................................................................................. 25

Interfacing to the OEM Electrical System ............................................................................................................................................................ 25

Body Builder Junction Block/Connector .............................................................................................................................................................. 26

EXTENDING OEM CIRCUIT GUIDELINES ............................................................................................................................................................... 26

Electrical System Interfacing Design Guidelines........................................................................................................................................................ 28

Design Guidelines ................................................................................................................................................................................................... 28

Cable (Wire) Selection Guidelines ....................................................................................................................................................................... 28

Cable Ampacity ................................................................................................................................................................................................... 28

Design Recommendations .................................................................................................................................................................................. 28

Cable (Wire) Types.................................................................................................................................................................................................. 29

Passenger compartment .................................................................................................................................................................................. 29

Engine compartment ....................................................................................................................................................................................... 29

Typical Calculation Example ................................................................................................................................................................................ 32

WIRE HARNESS ASSEMBLY GUIDELINES .................................................................................................................................................................. 33

Design Recommendations .................................................................................................................................................................................. 33

CONNECTING GUIDELINES ...................................................................................................................................................................................... 33

Design Recommendations .................................................................................................................................................................................. 33