Shore alternator and solar charging question?

[ON3ZTT]

Hi until now I had a Mastervolt 4 stage intelligent shore power charger and a Balmar anternator with intelligent 3 stage external charging regulator. They were never working at thesame time.
Now I will add 2 solar panels with eacht their own Mastervolt MPPT solar chargemaster regulators.
What happens when I'm on engine and the solar panels supply voltage at the same time? Any precautions to take?
What happens when I'm on shore power and solar at the same time?

Thanks

Jan
SY GOUDURIX
Belgium

[goboatingnow]

Nothing, both will contribute charge not equally but both will still contribute

[manitu]

This is a tough one..

First. When the engine is running, all other chargers will turn off , as they think the batteries are full.

The problem is shorepower/solar/wind. When two or more chargers run at the same time, none of them know that others are charging, and all of them will think that the battery is fuller than it is.

What you want normally:

Boat at home port: A shorepower charger that shuts off when the solar or wind is charging, and either a combined wind/solar controller , or priority to the one who delivers highest amps.

Out cruising: Shorepower charges at max when connected.

Using different brands you will struggle to make it work correctly, and you risk things like 70 amps of shorepower turned off because of 2 amps of solar charging.

You can, with some battery/electrical knowledge adjust float/bulk/absorb voltages for the different chargers , and try to predict how the system will behave, but it wont be perfect , far from it.

The only ways to get the most out of your charging system with multiple sources is to go for same brand with communication, or go for a all in one solution.

I'm not sure how the Mastervolt Masterbus system works in this regard , Victron also uses a bus-system.

I would go for a Victron system if I had the cash. A multiplus charger/inverter plus solar and wind controllers.

I think I'll go for a all in one solution like This one.

.manitu

[ON3ZTT]

Hi thanks for both replies.
Manitu, I don't understand why, in the case of the engine running, the solar power controller would see 'a full battery' (andcutback charging) and not inother situations eg shore power charger plus solar.
All chargers are intelligent,also the engine (Balmar alternator with external regulator).

What happens if I operate a double breaker in the solar panel leads to the controller, hence open circuit the solar array?

Another practical solution when moored in a berth would beto connect shore power but keep the dock charger off, only plug it in at night.

But those "switch off" solutions don't seem ideal, prone to error orforgetting toswitchback on when really necessary?

Jan

[noelex 77]

There are a great many misconceptions around this topic.

Batteries can only accept a certain charge rate depending on their SOC etc, so when presented with multiple charge sources if one charge source can provide the maximum current the batteries will accept, the other charge sources may effectively shut down. This does not indicate a fault.

With multiple charge sources there can be occasional real conflicts. These are can usually be resolved by adjusting the charge parameters, but at most they represent minor deviations from the ideal charge profile. Shutting off charge sources is rarely a good idea.

Geeks, such as myself who want the ultimate charge profile can adjust the advanced parameters to minimise the conflicts, but most users are better to not unduly worry.

If a charge source reduces its current, the most important question is whether the battery voltage is still maintained by the other charge sources. If the answer is yes, no practical conflict exists.

[goboatingnow]

Sheesh

When a battery is discharged the terminal voltage will be low.

All charge sources will contribute charge. The most powerful ( lowest output resistance ) will contribute the most. The charge into the battery will be at the acceptance level of the battery.

As the terminal voltage rises depending on exact cutoff points charge sources will decline or drop out. Again this doesn’t matter as the battery will accept the maximum it can from the sources supplying.

Eventually all charging will taper off.

So the answer is parallel sources just charge according to ohms law. There’s no issue during bulk phase , charge sources drop out during absorption according to various features but it doesn’t matter.

It only matters if you wish to give certain charge sources priority.

[ON3ZTT]

OK guys,

thanks for the answers.

I'll go forward with the installation of the solar panels.

Fair winds!

Jan
SY GOUDURIX
ON3ZTT