Mac Plus 48/12-50

Boost Your Service Battery

Too often, service batteries don’t get the charge they need. This is a problem made worse by smart alternators and start/stop systems, which result in slow and insufficient charges. The Mac Plus 48V and 36V solve that problem. With brand new bi-directional technology, the Mac Plus can use each side as an input or output, delivering a reliable and consistent charge to both service and starter batteries.

Proven Mastervolt Quality

The Mac Plus uses the proven Mastervolt 3-step+ charge algorithm, delivering a quick and easy charge, even to completely flat batteries. By knowing when the engine is running and providing charge, you can also be sure that the Mac Plus will never drain your starter battery.

A robust design holds up in even the harshest conditions, with battery temperature optimized charging and high-quality aluminium housing to ensure superior protection against dust and water ingress. The power efficient design also allows the Mac Plus to operate silently and without a fan.

Total Power Flexibility

With a wide DC input range, the Mac Plus allows all DC sources and can charge two batteries from a single alternator or charger. It supports a full range of chemistries and battery types, including lithium. And it also functions seamlessly with modern alternators such as Euro 5 and 6, ensuring proper charging by providing constant power, even when the alternator is inactive.

Parallel configuration of up to ten units will provide over 100 amperes. And advanced high-frequency technology with modern microprocessors ensures minimal power loss when switching from 36/48V to 12/24V and vice versa.

Analog voltage sense ports are also available to compensate for voltage drop and maintain proper charging.

Superior Monitoring & Control

Compatibility with CZone®, NMEA 2000® and MasterBus delivers truly superior monitoring and control, and ensures Mac Plus integrates easily into complete systems. Achieve the best performance possible via various controllers and high quality MOSFETs. And configure the Mac Plus with ease via MasterAdjust, the CZone configuration tool, or even via the on-board DIP switches.


  • Bi-directional technology
  • Get either 48V or 36V power from a single unit
  • Fast and safe charging, even during short trips
  • Fanless design for silent operation
  • Suitable for flooded, Gel, AGM and Li-Ion batteries (incl. LiFePO4)
  • Even charges fully depleted batteries
  • Engine run detection protects starter battery
  • Adjustable current limits to meet Euro 5/6 requirements
  • Voltage stabilization protects sensitive equipment, lights and loads
  • Parallel operation to obtain charging capacities well over 100 Amps
  • MasterBus, CZone and NMEA 2000 compatible, for intelligent system monitoring and automation
  • Temperature compensation and voltage sense for an optimal charging result
  • E-Mark/R10 certification for mobile applications
  • Power supply mode offers stable power for sensitive loads
  • Heavy duty connections for easy installation and quick set up via DIP switches

Product code: 81203105
download pdf


Specifications battery charger
Battery voltage sense Yes
General specifications
Status indicator Yes, 3 color double LED
Communication protocol MasterBus, CZone & NMEA 2000
Output voltage 10-15 V DC
Nominal output voltage 12 V
Output voltage stabilisation 2 % at extremes of temps, load and input
Output voltage ripple (peak peak) max. 1 %
Max. output power 750 W
Max. output current 50 A
Nominal input voltage 36/48 V DC
Input voltage range 32-64 V
Max. input current 25 A
Galvanic isolation No
Efficiency > 95 % (at nom. input voltage, full load); 97 % peak
Parallel configuration Yes, up to 4
Alarm contact Yes, through MasterBus, CZone, DIP Switch or remote switch
Engine run signal input Yes (active high/active low)
DIP switches Yes, for basic set up
Dimensions, hxwxd 255x165x66 mm
10.0 x 6.5 x 2.6 inch
Weight 1 kg
2.2 lb
Compliance CE, E-Mark, SAE J1171, ISO 8846 ignition protected, ABYC & UKCA
Technical specifications
Battery types Gel, AGM, Lithium Ion, user defined
Power consumption < 5 mA, < 10 mA in CZone, < 1 mA in MasterBus
Temperature range (ambient temp.) - 25 °C to 60 °C; derating > 40 °C/104 °F
Cooling Natural cooling
Protection degree IP23
Protections Overload, over-temperature, DC short circuit, reversed polarity (fuse)



Mac Plus 48/12-50

Brochure Mac Plus Series



Mac Plus 48/12-50


User manuals

Mac Plus 48/12-50

User manual Mac Plus 48V


Product image

Mac Plus 48/12-50 Small »
Medium »
Large »


Mac Plus Installation Video

Mac Plus 36_48V Launch Video

Mac Plus Product Explainer


Temperature sensor 6m

This temperature sensor is included with ChargeMaster (Plus), Mass Charger, CombiMaster, Mass Combi... View product

Temperature sensor 15m

Can be ordered separately. View product

EasyView 5

Waterproof System Monitor with 'daylight readable' display and intuitive touchscreenControlling... View product