Troubleshooting a Mastervolt Lithium System

[donradcliffe]

I just delivered a race boat with a 3 battery Mastervolt lithium system. The install was all Mastervolt with C-zone remote control system to further complicate things.

I delivered the same boat with the same system 2 years ago, and all was great. It only took one hour of charging for every 24 hours of sailing to keep the batteries happy. Then covid hit, and the boat sat at the dock except for a couple of 3 hour trips to the boatyard.

This time I arrived to a dark ship. The it had gone out for a 4 hour test sail 2 weeks ago, and they had some trouble getting the batteries on line, but then everything worked. I had been on shore power for 24 hours prior to my arrival. The C-zone hooked all the boat systems up while on shore power, but went dark when unplugged.

The engine started fine on its own battery and alternator, and the house alternator was putting out enough power to run the boat. When I attempted to manually pull the relays in for the house batteries while the engine was o, they the battery protection system tripped them off after about 60 seconds.

There was no Mastervolt documentation on the boat. The analog multimeter on the boat was not accurate enough to determine SOC from the batteries, but I assumed they were getting a low voltage cutoff which tripped them off --even when there was a charging source available. All of the fancy digital readouts for the house battery voltage and current showed dashes.

I had a tight weather window and an approaching hurricane, and gave up on Mastervolt support after 20 minutes on hold. I did send someone out to buy jumper cables, and left, figuring the boat could last 48 hours if I kept the engine on.

Needless to say at 0300 the first night, the house alternator stopped putting out and things went dark again. I took a jumper cable from the start battery to the back of the distribution panel, and ran on the start battery alternator the rest of the trip.

Had pretty good weather the 360 miles of the delivery, with no more drama. Texted the owner's rep and told him he needed a really good electrician on the boat today if he wanted to race on Thursday. Borrowed a DVM and measured the voltage on the LiFe batteries. One was 5.6 V, one 10.8v, and one was 12.7v. The second alternator is shoehorned into a corner of a hot engine, but my guess is that it and/or its external regulator may need replacing.

When I left the boat, we had the 12.7v battery pulled in and were attempting to charge it with the shore power charger, but I never did figure out how to recover from a low state of charge. The battery at 6v is probably headed for the scrap heap, but they can do day races on even one battery if they fix the alternator.

Lessons learned:

Don't let them install a fancy lithium system in your boat without providing a circuit diagram and detailed WRITTEN instructions for its care. I think that the whole problem could have been avoided or the failure(s) detected earlier.

Don't let anyone install remote relays in place of battery off/on switches in a boat which goes offshore. KISS.

Don't forget to pack your clamp on ammeter in your boat delivery bag.


Does any one with Mastervolt lithium battery system know how to recover from an undervoltage cutoff? Is there a separate BMS inside each battery?

[donradcliffe]

I found the online manual, and discovered that Mastervolt has two low voltage "Safety" events.

The resettable safety event occurs with a voltage below 12v for 10 seconds. You can recover by immediately hooking up a charging source and manually closing the safety relay--once.

The non-resettable safety event occurs with a voltage below 11v. You are instructed to shut off your 12v system and call your Mastervolt Dealer. It's like the message you get from your common rail diesel engine ECU--your boat is now useless.

Buried in page 18 of the manual " it is highly recommended to charge the battery to > 80% of its capacity every 100 days."

[smac999]

I bet all 3 batteries feed a single blue sea swtich. so a bms event for any battery shuts off the whole bank. it could have been built with 3 swtiches one for each battery, as each mastervolt battery has it's own bms. then the battery still over 12v would still be feeding the bank. if one is 12v and some are at 6v then I'd guess 2 battereis failed.

it sounds like you should have layed up at dock when it all died. running the boat like that was compleatly irresponsible. you could have destroyed everything (all nav electronics etc) running the alt with no battery. your lucky if the only thing dead is the alt.

[donradcliffe]

Originally Posted by smac999

I bet all 3 batteries feed a single blue sea swtich. so a bms event for any battery shuts off the whole bank. it could have been built with 3 swtiches one for each battery, as each mastervolt battery has it's own bms. then the battery still over 12v would still be feeding the bank. if one is 12v and some are at 6v then I'd guess 2 battereis failed.

it sounds like you should have layed up at dock when it all died. running the boat like that was compleatly irresponsible. you could have destroyed everything (all nav electronics etc) running the alt with no battery. your lucky if the only thing dead is the alt.

You would lose that bet. While each battery had its own blue sea switch, when one battery hit a safety event the system opened all three switches and took the boat dark.

As of now, all three batteries and the alternator are back on line after Mastervolt used their secret PIN and overrode the system safety protection. It would be irresponsible to tell you what that PIN is.

As far as waiting to fix the electrical system in LA, you have obviously never delivered a race boat up the California coast. The boat is ready to race. If I had waited a day the boat would still be at sea and could be suffering structural damage.

[skipperpete]

Originally Posted by donradcliffe

You would lose that bet. While each battery had its own blue sea switch, when one battery hit a safety event the system opened all three switches and took the boat dark.



As of now, all three batteries and the alternator are back on line after Mastervolt used their secret PIN and overrode the system safety protection. It would be irresponsible to tell you what that PIN is.



As far as waiting to fix the electrical system in LA, you have obviously never delivered a race boat up the California coast. The boat is ready to race. If I had waited a day the boat would still be at sea and could be suffering structural damage.

Was the boat fitted with a common rail engine, I’m a bit puzzled that none of the discussions here ever mention protecting (at all costs) an ECU controlled engine from the type of surges that can apparently occur with emerging technology storage cells.
Pete.

[donradcliffe]

The boat has a 3 year old Yanmar 4JH80 saildrive system, turbo with common rail. AFAIK, the engine electronics are driven by the engine start battery and the engine start battery alternator, which were completely separated from the house electrical system, until I used a jumper cable to power the boat from the start battery alternator.

The boat was not broken during the regatta, so the trip back down was a good one. Dock to dock was 420 miles in 42 hours, and top speed was 18k with a small delivery main and a #3 jib. The house electrical system performed well with the one bad battery out of 3 isolated--batteries were at 80% after 32 hours of sailing with the engine off.

[shimari]

You hit the main gripe I have with Mastervolt. There just isn't much information available online, and you're at the mercy of the dealer's schedule.

We had a similar problem while in the UK. One cell in a battery was tripping the system. Fortunately, it only tripped it's bluesea breaker. The other battery in parallel was able to keep things going.

The tech support number is likely vastly over worked, but I've found them more than helpful.

[Journeyman]

Don,

I interpret the MV spec differently for the Resettable case. I think they are saying between 12V and 11V you can continue to attempt recharging the battery to get the voltage up with an indefinite number of retries.If you are unsucessful every 60 secs it goes off line again.

Only if you drop below 11V does it become un-resettable.

Also, did you ever learn how all 3 Safety Relays tripped rather than just the one for the bad battery(s)?

Eddie