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1.2 START battery Distribution (Driver Wheel Well)

Odyssey PC1500 Battery Terminals

Overview

The START battery (driver wheel well) provides power for critical engine and safety systems:

  1. Direct high-current → Starter (no CB), alternator charging input (no CB)
  2. Circuit breaker protected → PMU (250A CB), BCDC (80A CB)
  3. Direct low-current → ECM, grid heater (fusible link protection)

See Circuit Breakers for complete CB specifications. All CBs mounted in wheel well within 7" of battery (code compliant).

Single Source of Truth

This page is the authoritative source for all START battery wire specs (gauge, distance, voltage drop). Component pages reference here. For battery specs see Section 1.1. For ground bus bars see Section 1.5.

START battery Positive Terminal (6 connections)

Circuit Destination Wire Gauge Distance Current Voltage Drop Protection
Alternator Engine bay 2/0 AWG 8 ft 270A 2.81% @ 60°C None
Starter Engine bay 2/0 AWG 6 ft 400-600A 1.9-3.9% @ 20°C None
PMU24 Engine bay 2/0 AWG ~7 ft 250A max 2.4% @ 60°C 250A CB
ECM Engine bay Per Cummins Short <5A Negligible Fusible link
Grid Heater Engine bay Per Cummins Short ~80A Negligible Fusible link
BCDC Alpha 50 Passenger wheel well 4 AWG ~6 ft 50A 0.94% @ 20°C 80A CB

All circuit breakers mounted within 7" of battery (ABYC/NEC compliant). See Circuit Breakers.

START battery Negative Terminal (7 connections)

Circuit Destination Wire Gauge Distance Current Voltage Drop
Engine Bay Ground Bus Engine bay 2/0 AWG ~8 ft 600A+ peak <0.1V @ 60°C
ECM Engine bay 12 AWG Short <5A Negligible
Grid Heater Engine bay Per Cummins Short ~80A Negligible
AUX Battery Passenger wheel well 1/0 AWG 5-6 ft 75A max <0.05V @ 20°C
G1 GMRS Radio Dashboard 10 AWG ~8 ft 15A TX 1.2% @ 20°C
STX Intercom Dashboard 10 AWG ~8 ft 5A 0.4% @ 20°C
Ham Radio Dashboard 10 AWG ~8 ft 13A TX 1.0% @ 20°C

Radio grounds direct to battery for RF noise isolation. ECM/grid heater via Cummins harness to isolate from starter spikes.