ChargeMaster Plus 12/50-3 (44310505)
Mastervolt ChargeMaster Plus 12/50-3 wiring diagram
12V charger with three positive outputs sharing 50A total and a common negative. Any output may receive the full available current; the unit does not provide 50A simultaneously to each bank. Accepts 80–275VAC and supports standalone, MasterBus or CZone operation.
- Nominal voltage
- 12 V
- Compatible systems
- 12 V
- Rated output
- 50 A
Wiring diagram
How the ChargeMaster Plus 50A is wired.
Open this example in Crimp to use your own parts and cable lengths. Review the assumptions and installation notes as you adapt the circuit.
The example connects one charger output to one placeholder house bank using 25 mm² over 3.048 m and a 60 A battery-positive fuse. The three outputs share the charger's 50 A total; adding banks does not provide 50 A to each simultaneously. Other outputs, AC supply, protective earth and communications remain for installation planning against the full manual. Manufacturer installation manual
Edit this wiring exampleCable sizing for this example
Use the diagram as a starting point for your installation. Replace the example equipment and cable lengths with your own, and check the connections against your exact model's instructions.
10 ft one way
12 V system
- Wire
- 4 AWG · 25 mm²
- Example fuse
- 60 A
- Design current
- 50 A
- Voltage drop
- 1.8%
Sized against ABYC E-11. The design current is the unit's rated output. The length is one way; voltage drop includes an equal-length return.
Run-length and manufacturer assumptions
The editable example uses 3.048 m (10 ft) runs unless a shorter run is stated. Metric overviews round these to 3 m. Adapt the parts and lengths to your installation before choosing cable and protection.
The example connects one charger output to one placeholder house bank using 25 mm² over 3.048 m and a 60 A battery-positive fuse. The three outputs share the charger's 50 A total; adding banks does not provide 50 A to each simultaneously. Other outputs, AC supply, protective earth and communications remain for installation planning against the full manual. Manufacturer installation manual
Supporting parts
- 20 ft total of 4 AWG (25 mm²) marine cable
- Terminations for 4 AWG cable, matched to the equipment's screw terminals, leads or studs
- 60 A fuse and holder on the positive run
- Heat-shrink, strain relief and terminal boots sized to the cable
Check stud sizes, fuse type, run length and how warm the space gets against the gear you actually have before you order.
Installation notes
Before you install.
Open a question for model-specific guidance and sources.
Verified against the manufacturer's documentation (rev. 10000016594/05 archived; current manufacturer revision /06 cross-checked online), checked 2026-10-01. Manufacturer documentation →
What does “12/50-3” mean?
The ChargeMaster Plus 44310505 has three positive battery outputs and a common negative. 50 A is the shared total: one output can receive the full available current, but three connected banks do not create 150 A. This is the Plus model, not the older ChargeMaster.
How are the cables and fuses connected?
Connect DC 1/2/3 positives to the respective banks, each with protection at its battery, and the common negative to the system return/shunt side. Manual pages 8–9 specify 60 A DC fuses, 16 mm² below 3 m, and 25 mm² for 3–5 m. Do not use the chassis as the negative conductor. Main DC connections tighten to 4.9–5.4 Nm.
The AC input requires the appropriate line/neutral or split-phase wiring, protective earth and an accessible disconnect. A DC-negative cable does not replace protective earth.
What must be set before charging?
Select the battery profile with the documented DIP-switch/network procedure. Confirm lithium voltage limits with the battery maker; network connectivity alone does not establish BMS shutdown compatibility. When shore capacity is limited, configure AC current control to fit the available supply rather than reducing cable protection arbitrarily.
How should it be mounted and checked?
Mount vertically with cables down, clear cooling paths and protection from water, salt and battery gases. Output derates in heat. Verify each bank’s voltage and charging behavior separately. The archived manual is revision /05; current revision /06 is also linked for later installation changes. Automatic current sharing is not modeled as a guarantee of 50 A to every drawn branch.
Technical reference
Specifications and terminal map.
Check the model, ratings and connection points against your own unit before choosing installation hardware.
Catalog specification
12V charger with three positive outputs sharing 50A total and a common negative. Any output may receive the full available current; the unit does not provide 50A simultaneously to each bank. Accepts 80–275VAC and supports standalone, MasterBus or CZone operation.
- Nominal voltage
- 12 V
- Compatible systems
- 12 V
- Rated output
- 50 A
Terminal map
Catalog connection points, current direction and planning limits. Check the manufacturer's pinout and connector ratings before installation.
AC L
neutral · input
AC N
neutral · input
AC PE
ground · input
DC 1 +
positive · output
DC 2 +
positive · output
DC 3 +
positive · output
COMMON −
negative · output
Sources and sizing method
Equipment specifications. Model details, ratings and terminal roles come from the catalog. Check your unit’s label and current manufacturer documentation for its exact revision.
Example sizing. Sized against ABYC E-11 — the US reference, and what Transport Canada accepts as an alternative to TP 1332 for pleasure craft under 24 m. Results use the example current and run length shown above. Set your actual equipment, lengths and installation conditions in Crimp before choosing hardware.
Read how the sizing worksNext step
Plan your installation with ChargeMaster Plus 50A.
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