Auto Charging Relay 12V, 140 AMP
The automatic charging relay (ACR) automatically manages battery charging to ensure maximum efficiency and protect your batteries.
Features:
- Automatic battery managementconnects batteries during charging and isolates them when the voltage drops
- Start Isolation (SI)protects sensitive electronics during engine cranking by temporarily disconnecting house loads (indicated by a slow-flashing yellow LED)
- High-output supportcompatible with alternators up to 120A
- Dual-color LEDsprovide real-time battery status: Fault, Charging, Discharging, Combine, SI, and Override modes
- Under Voltage Lockoutprevents the relay from closing when battery voltage is too low (9.5V for 12V systems, 19V for 24V systems)
- Durable designIP67 waterproof, ignition protected, safe for marine and RV applications
Specifications:
- Continuous Rating: 120 Amps
- Intermittent Rating: 140 Amps
- Max Voltage: 48VDC
- Cable Size: 4/0 AWG
Applications:
- Boatsdual battery systems (starter + house)
- Sailboatsnavigation and lighting batteries
- Fishing boatstrolling motor and accessory battery protection
Specifications:
- Continuous Amperage: 120
Quick Guide (pdf)






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