Blue Sea SI-ACR-Series Automatic Charging Relay - 12V/24V (120A)

Automatically combines batteries during charging, isolates batteries when discharging and when starting engines.

Features

• Dual sensing
• Designed for 12 V or 24 V systems
• 12/24 V auto ranging voltage input
• Hermetically sealed contacts/vaporproof
• Supports high-output alternators up to 120 A
• Ignition protected-safe for installation aboard gasoline powered boats
• Protects sensitive electronics by temporary isolation of house loads from engine circuit during engine cranking
• Start Isolation allows temporary isolation of House loads from Engine circuit during engine cranking to protect sensitive electronics from sags and spikes
• Remote LED remotely indicates ACR states - requires optional LED

Specifications

• Stud material: Tinned copper
• Nominal voltage: 12 V/24 V DC
• Continuous rating: 120 A
• Start isolation: Yes
• Amperage operating current (combined): 175 mA
• Amperage operating current (open): 15 mA
• Terminal stud torque: 15.82 N-m (140 inch-lb)
• Intermittent rating (5 min): 210 A
• Cable size to meet rating: 1/0 AWG
• Terminal ring diameter clearance: 1.12" (28.45 mm)
• Terminal stud length: 0.875" (22.23 mm)
• Terminal stud size (M10): 3/8"-16
• Relay contact position (combine 30 sec): 13.6 V @ 12 V, 27.2 V @ 24 V
• Relay contact position (combine 90 sec): 13.0 V @ 12 V, 26.0 V @ 24 V
• Relay contact position (open 10 sec): 12.35 V @ 12 V, 24.7 V @ 24 V
• Relay contact position (open 30 sec): 12.75 V @ 12 V, 25.5 V @ 24 V
• Relay contact position (open high): 16.0 V @ 12 V, 30.0 V @ 24 V
• Relay contact position (over voltage lockout): 16.0 V @ 12 V, 32.0 V @ 24 V
• Relay contact position (under voltage lockout): 9.5 V @ 12 V, 19 V @ 24 V
• Weight: 0.57 kg (1.25 lb)

Certifications

• CE
• IGNITION PROTECTED
• IP67
• ISO 8846 Marine
• SAE J1171 Marine
• UL 1500

Dimension Drawing

LED Status Chart

Wiring Diagram

Manual Battery Management and ACR SubSystem

SI-ACR automatically combines batteries during charging, isolates batteries when discharging and when starting engines. The Dual Circuit Plus Battery Switch simplifies the switching of two batteries to OFF or ON while still providing battery isolation between the engine and auxiliary battery. The Combine function can be used to parallel the batteries in the event of a low engine battery.

Technical Files

Diagnostic Flowchart
Installation Instruction