Mastervolt Lithium Ion System Problems

The boat has been retrofitted with a 30 kW Mastervolt Lithium Ion system (a 103.000 EUR option). All of the inverter units have been installed in the lazarette area where the generator is located. Princess was fitting this system for the first time in their history whereas we had years of experience with it. We have warned them about certain potential issues which they chose to ignore. Unfortunately, these lead to consequences shortly after installation.

Lazarette area where all of Mastervolt components have been fitted. Before even summer hit, we started experiencing extreme ambient temps and related overheating problems in the area despite our numerous warnings during installation.

Picture of the area annotated with component descriptions. 2x Mastervolt Combi units paralleled seen side by side on the right of the image.

Mastervolt Ultra Combi Unit Failed

The system included 2x paralleled Mastervolt Ultra Combi inverters capable of sypplying 7kW continuous (14kW peak) power to hotel appliances. During one of our outings, the system failed for no apparent reason.

Top and bottom LED indicators red lit meant system failure 

Mastervolt Easyview screen confirmed the failure with an alarm message

All other inverters went offline following failure of one of the inverter/chargers

Although one of the Mastervolt inverter/chargers had failed, the other one went offline as well leaving us without inverter power onboard. We informed Princess about the issue in detail and sent them some pictures and asked them to arrange attendance of a Mastervolt technician asap to at least reprogram the system to run on single inverter until the faulty one is replaced. We obviously had to go back to our home port as we did not want to keep the genset running to charge our phones or ipads.

Once at the home port, a Princess technician came onboard to check the problem and reported back. The issue was clear, the Mastervolt Combi unit had failed and needed replacing.

After 6 days of waiting time, a Mastervolt tech came onboard to reprogram the unit to work on single inverter.

It took another 4 days at the marina until a new Mastervolt Combi unit has been finally sourced and brought onboard to be replaced with the faulty one. A technician from Mastervolt attended and replaced the unit, which took about 3 hours. The system needed to be reprogrammed properly but for some reason the technician had to rush out to another project after installing our unit. The inverter/charger was operational but features such as turning chargers on/off or setting current limits for load management could not be done. We had to wait another 6 days for them to come back and reprogram the system properly.
Status: Fixed in 16 days

Reprogramming could have been done remotely, but...

Our order included a Masterbus USB interface and an Amperian unit which have been fitted to the tech area underneath main helm exactly for these reasons. The system could be programmed in 2 ways:

(1) Via connecting a laptop to the Masterbus USB interface
(2) Via Amperian unit by giving online access to Mastervolt technicians

Days of waiting time at the marina could have been avoided altogether if a Princess technician (Princess dealer retrofitted this 103.000 EUR system) came onboard and connected to the system with their laptop to let Mastervolt engineers access and work on the system remotely.

Masterbus USB interface (left) and Amperian module (right) installed under main helm dashboard

Little Roof for Genset Battery Charger

We have also ordered a genset battery charger, or rather a DC/DC converter, to be able to charge our generator battery with our lithium battery bank. We have been charged 1400 EUR for this installation (640 EUR material, 760 EUR installation). We noticed that this electronic device has been installed in the lazarette area, right underneath the engine room access hatch, quite exposed to water/dust/debris that might fall into the lazarette when you open the engine hatch. This was obviously the easiest location for the installation (Should 760 EUR have done better?!). We have asked Princess to relocate the charger to another spot less exposed. They said it was a big job and put up a "roof" on top of the charger instead. 

Status: "Fixed" in 6 days

Before

After

M/Y Guinea Pig 

We have asked Princess to arrange a Mastervolt technician to be onboard during handover trials to explain the system and answer our specific questions, but they persistently avoided to bring them in. Instead, a 22 year old junior Princess electrician from Plymouth factory was put in charge of the system. He was the one who installed the devices as per an electrical engineers' instructions. It was his first time dealing with a Mastervolt system and he had no idea how the system parameters worked. He could not answer any of our questions neither brief us about how the system worked. We understand that profit margins might be higher if the system is installed inhouse, but evidence shows that they struggled with hit and misses. We do not know how these devices were initially connected and under which conditions they were operated without the supervision of an authorized Mastervolt engineer. We have reason to believe that the chain of events might have resulted in the failure of the device, which happened for no apparent reason.

Word of advice: If you intend on fitting a complex system that require a high level of engineering skills, make sure that the installation is handled by the capable hands and under the supervision of an authorized installer.