Starting Isolation Dual Sensing Automatic Charging Relay


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Model # 8646283 | Mfg # 7610 | UPC # 632085076108

This relay will protect your sensitive electronics by temporarily isolating the house loads from the engine circuit during engine cranking.

The Blue Sea Systems Starting Isolation Automatic Charging Relay automatically combines battery banks during the charging cycle and isolates them while discharging, plus protects sensitive electronics by temporary isolation of house loads from engine circuit during engine cranking. Provides 120 continuous amps at 12/24V, 210A for 2 minutes and 280A for a 5 second surge. Ignition-protected for use aboard gasoline powered boats. Remote LED output indicates relay state away from ACR. LED light indicates when batteries are combined. Supports high-output alternators up to 120A. Dimensions are 3 7/8"L x 3 1/2"W x 1 7/8"H. The relay is waterproof rated at IP67 for temporary immersion for 30 minutes. Five-year warranty.

Key Features

  • Designed for 12V or 24V systems
  • 12/24V auto ranging voltage input
  • Dual sensing
  • Automatically combines batteries during charging
  • Isolates batteries during engine cranking and when not charging
  • Senses charge source on either battery bank
  • Under voltage lockout won't close when the lower battery is below 10.8V @12V (21.6V @24V) operation
  • Hermetically sealed contacts/vaporproof
  • Ignition protected for use aboard gasoline powered boats
  • Waterproof rated at IP67 for temporary immersion for 30 minutes
  • ISO 8846 and CE approvals
  • Meets SAE J1171 external ignition protection requirements

SI-Series Automatic Charging Relay Brochure


Additional Instructions

Dimensioned Drawing - Cover Off

Dimensioned Drawing - Cover On

120 Amp SI ACR Comparison

 WARNING: Cancer and Reproductive Harm -


Starting Isolation Dual Sensing Automatic Charging Relay

Name Value
Amperage 120 Amps
Multi Bank Chargers 2 Banks
Type Battery Isolator/Combiners
Voltage 12/24 Volts DC


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To receive your order by December 24th, 2018, please reference the 2018 Holiday Shipping Schedule.

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