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Blue Sea ML-Series Heavy Duty Automatic Charging Relay, 12V, Manual

Item # 85122
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  • Manages the charging of two large battery banks

  • Allows paralleling of banks for emergency starting

  • Magnetic latch draws low to moderate current

  • LED output indicates combined & isolated batteries

  • Includes ML-Series Remote Control Contura Switch

Product Summary 

The Blue Sea automatically manages the charging of two large battery banks and allows the paralleling of battery banks for emergency starting. 500A continuous rating supports high-output alternators. Magnetic Latch ACR draws very low current (<40mA to monitor terminal voltage) in the "ON" or "OFF" states, and draws moderate current for very short time when changing state. Senses charge on both battery banks. Start Isolation can be configured for temporary isolation of House loads from Engine circuit during engine cranking to protect sensitive electronics. Engine Isolation can be configured for isolation of two engines while both are running to protect engine electronics and maximize alternator output. LED output to remotely indicate when batteries are combined, isolated, in voltage lockout, or in Start or Engine isolation. Label recesses for circuit identification. Includes ML-Series Remote Control Contura Switch.

• Sixteen 3/8" tin-plated copper studs (1.50"L) for maximum conductivity and corrosion resistance (recommended torque: 140 in-lb)
• 7/8" stud length accepts multiple cable terminals
• Silver alloy contacts provide high reliability for switching live loads
• Cranking Rating: 2,500A (10 sec.); 1,100A (1 min.); 700A (5 min.)
• Continuous Rating: 500A
• Rated Switch Cycles: 100,000
• Amperage Operating Current: <40mA (continuous), <7.0 Amps (when changing state)
• Cable Size to Meet Ratings: 4/0 AWG x 2
• Terminal Ring Diameter Clearance: 1.12"
• Live Current Switching: 300A @ 12V DC (10,000 Cycles)
• Combine: 13.5V @ 12 Volts / 27.0V @ 24 Volts (30 sec.), 13.0V @ 12 Volts / 26.0V @ 24 Volts (90 sec.)
• Open: 12.35V @ 12 Volts / 24.7V @ 24 Volts (10 sec.), 12.75V @ 12 Volts / 25.5V @ 24Volts (30 sec.), 16.2V @ 12 Volts / 32.4V @ 24 Volts (high)