Przekaźnik automatycznego ładowania ML-ACR – 12 V DC 500 A

The BLUE SEA ML-ACR 500A (part number PN 7620) is a robust automatic charge relay designed for demanding marine and automotive applications. It manages two battery banks by automatically combining them during charging and isolating them when no charging is detected. This model can handle high-efficiency alternators and large battery banks thanks to its continuous capacity of 500 amperes.

The Magnetic Latching (ML) technology is a key feature of the ML-ACR 500A relay. It ensures extremely low current consumption when the relay is in the ON or OFF state. The relay only draws moderate current during the very short period when it changes state (approximately 20 ms), which optimizes battery life by reducing continuous current draw.

The ML-ACR 500A offers configurable isolation functions to protect sensitive onboard electronics:

Start Isolation (SI): Temporarily protects house loads from the engine circuit during engine start, preventing voltage drops and spikes.Engine Isolation (EI): Allows isolation of two running engines to protect their electronics and maximize alternator output.Note that the ML-Series ACR can be configured for either Start Isolation or Engine Isolation, but not both simultaneously.

The ML-ACR 500A relay automatically combines battery banks when the detected voltage reaches:

Above 13.5V for 30 secondsAbove 13.0V for 90 secondsIt automatically isolates the battery banks when the detected voltage drops to:

Below 12.35V for 10 secondsBelow 12.75V for 30 seconds

The ML-ACR 500A relay integrates protections against extreme voltages for 12V DC operation:

Undervoltage Lockout: Prevents battery combining when either battery is below 9.6V.
Overvoltage Lockout: Prevents battery combining when either battery is above 16.2V.
These mechanisms protect the relay from overvoltages and high peak currents, as well as batteries from excessive discharge or overcharging.

Yes, the ML-ACR 500A relay is designed for durability in harsh environments. It is rated IP66, meaning it is protected against dust and powerful water jets. Additionally, it features tinned copper studs for maximum conductivity and corrosion resistance, as well as silver alloy contacts for high reliability when switching loads under load.

No, the ML-ACR 7620-BSS model is designed for fully automatic operation and does not include an integrated manual control. The PN 7622 and PN 7623 models from the ML-ACR series are the ones that feature manual control.

The control circuit of the ML-ACR 500A relay has a current consumption of less than 40 mA.

The ML-ACR 500A standard (PN 7620) is optimized for AGM/GEL to AGM/GEL or AGM/GEL to lithium battery configurations. For systems using lithium batteries in lithium-to-lithium or lithium-to-lead-acid configurations, the ML-ACR Li-Ion version is recommended, as it is specifically designed for these applications.

No, the ML-ACR 500A model (PN 7620) is specifically designed for 12V DC systems. Other models in the ML-ACR series (e.g., PN 7621 or PN 7623) are designed for 24V DC systems.

Yes, the ML-ACR 500A is designed to support high-efficiency alternators and large battery banks. Its continuous 500A capacity allows it to efficiently manage power distribution and optimize charging performance even under demanding conditions.

The ML-ACR 500A can be remotely controlled using a Contura switch (SPDT) with three positions (ON-OFF-AUTO). This type of switch allows forcing battery bank combinations, isolating them, or letting the relay operate in automatic mode. A momentary switch (SPDT) (ON)-OFF-(ON) or a momentary pushbutton can also be used to ensure battery cross-connection and/or isolation.

For the ML-ACR 500A relay to reach its continuous rated capacity of 500A, it is recommended to use a 2x 4/0 AWG (2x 120 mm²) cable. This wiring will handle a starting current of 1450A (30 sec) and an intermittent current of 700A (5 min).

The ML-ACR 500A is fitted with 3/8"-16 terminal studs. The recommended maximum tightening torque for these studs is 140 in-lb (15.8 N•m). It is critical to adhere to this torque to ensure a secure connection and prevent damage to the relay.

The ground wire of the ML-ACR 500A must be connected to a common ground or directly to the battery’s negative terminal. A correct ground connection is essential for the relay to function properly.

The ML-ACR 500A relay provides an LED output to remotely indicate battery status. If the remote switch LEDs are off, the batteries are isolated. If the LEDs are on, the batteries are combined. Specific LED flashes also indicate conditions such as start/engine isolation, undervoltage or overvoltage lockout.

The physical dimensions of the ML-ACR 500A relay are as follows:

Width: 3.75" (95.3 mm)
Height: 5.47" (138.9 mm)
Depth: 2.03" (51.6 mm)

The startup insulation (SI) or engine insulation (EI) configuration depends on how the inputs are wired. The detailed instructions provided with the product describe the specific wiring diagrams for each function. It is important to note that the relay can be configured for either of these functions, but not both simultaneously.

Yes, the ML-ACR 500A relay is ignition-protected. It is certified to meet external ignition protection requirements per ISO 8846 and SAE J1171 standards, making it safe for use in engine compartments where flammable vapors may be present.