Mastervolt 100A Chargemaster PLUS (12v/100A - 3)

FREE DELIVERY* - A 100 amp battery charger with three outputs - that can also use your alternator output to charge your batteries

£1,059.99 (inc. VAT)
VAT Content: £176.67


Mastervolt Chargemaster PLUS 12/100-3

Chargemaster plus is the next generation of battery chargers that integrates multiple functions into one single device. Replacing auxiliary chargers, battery isolators and VSR (voltage sensitive relay), Chargemaster plus reduces system complexity and cost. Designed for versatility, it charges virtually any combination of three batteries in a fast and safe way anywhere in the world.


  • It can handle worldwide AC voltages and frequencies, so if you are lucky enough to be using your boat in multiple countries then this unit takes the worry out of shore hook-up.
  • The charging output is split as needed across up-to three separate batteries or battery banks.
  • When underway the output from the alternator can be put back through the Chargemaster and distributed to all three battery banks........hence turning your alternator into a three-step-plus smart battery charger.
  • With one unit to take care of both shore power charging and alternator charging distribution then you have one capable unit rather than multiple units


  • Multicharger with two outputs, one input/output, DC-DC converter, current limiter and VSR
  • Combine Lithium Ion, Gel, AGM or Wet lead-acid, and large or small battery banks all with one charger
  • 80-275V AC input at 35-70HZ
  • Compact, easy to connect and install
  • Battery temperature sensor included
  • Revival mode: automatically revives even fully depleted batteries
  • Priority Charge: sends available power to the lowest battery for faster charging
  • Smart input: charge all three batteries from one single alternator for continuous charging on the go 

The common sense bit.... 

So aside from all the jargon, what does this thing actually do?. We firstly it is a battery charger, so it takes a mains input from a shoreline or generator, converts it to 12v and can then use that to charge up to three separate batteries (or battery banks). The new part is that the third output is called the smart-output, this can also act as an input from an alternator. Basically the smart-output is connected to the starter battery, then when the mains power is disconnected and the engine is running it will recognise that the starter is being charged by the alternator; then it will accept the alternator charge current (limited to a maximum of 40A allowed through) and use it to charge the other batteries (or battery banks). So in effect it takes the relatively unsophisticated output from your alternator and then splits it and uses is to charge your batteries using its sophisticated three-stage-plus charge cycle.

Technical Specifications

General specifications
Nominal output voltage 12 V
Max. charge current per output 100 A
Smart In-/Output output voltage 12 V
Smart In-/Output output current 5-40 A (adjustable)
Smart In-/Output input current max. 40 A
Max. AC current (230 V / 120 V) 8.5 A / 17 A
Total charge current 100 A at 14.4 V
Number of battery outlets 3 (max.)
Battery capacity range 400-1000 Ah
Nominal input voltage 120/230 V (80-275 V) 50/60 Hz
AC connection screw terminals, suitable up to up to 6 mm²
Power supply mode yes
Display/read-out LED display
Dimensions, hxwxd 384 x 250 x 127 mm
15.1 x 9.8 x 5.0 inch
Weight 5.9 kg
13.0 lb
Approvals CE, ABYC, UL1236, SAE J1171, ISO 8846, CEC, RCM/C-Tick
Technical specifications
Charge characteristic IUoUo, automatic / 3-step+ for Gel/AGM/Lithium Ion/traction/spiral
Temperature compensation -30 mV/°C / -17 mV/°F; temperature sensor included
DC voltage compensation through MasterShunt
Power consumption (DC side) < 2 mA (MasterBus off)
Current Control function yes, through MasterBus
Power factor control > 0.98
Temperature range (ambient temp.) -25 °C to 80 °C, derating < 0 °C and > 40 °C
-13 °F to 176 °F
Cooling vario fan
Protection degree IP23, vertical mounting
Protections over-temperature, overload, short circuit, high/low battery voltage, ignition protection
MasterBus compatible yes
Charger Status Interface (alarm contact) yes, using a Multipurpose Contact Output (product code 77030500)

Additional pictures




21 Waterside, Ely, Cambridge, CB7 4AU


01353 663 095
01353 640 008

Opening Hours:
Monday  9am-5pm (web only)
Tues - Fri  9am-5pm
Saturday  10am - 2pm
Closed on a Sunday


We are a real walk in the door shop, staffed by real boaters, if you want to talk to us about any of the products on this site (or any other of your chandlery needs) then please feel free to give us a call

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