Mastervolt Charge Mate Pro 40 Electronic Charge Relay

The Mastervolt Charge Mate Pro 40 is a high-efficiency electronic charge relay designed to effectively distribute alternator or charger current between two battery banks. By connecting both batteries during charging and isolating them during discharge, it helps protect your primary battery from draining while ensuring your service or bow thruster battery receives priority charging.

This device features current limiting to the secondary battery, automatic 12/24V detection, and unidirectional flow control that blocks reverse current. It is housed in a corrosion-resistant, IP65-rated casing with integrated aluminum heat sinks for reliable performance in marine and mobile environments.

• Charging Capacity: Limited to 40 A for the secondary battery.
• Input Voltage: 9-32 V DC.
• Battery Compatibility: Suitable for all battery types, including Lithium Ion.
• Monitoring: LED status and warning indication.
• Dimensions: 6.2" x 5.5" x 3.1" (157 x 140 x 80 mm).
• Weight: 1.9 lb (0.88 kg).
• Operating Temperature: -40 °F to 140 °F (-40 °C to 60 °C).
• Emergency Start: Supports optional bypass switch for emergency engine starting.
• Approvals: CE certified.
• Regulatory Note: This product contains chemicals known to the State of California to cause cancer, birth defects, or other reproductive harm.