Connecting Charging Sources

[nigel1]

In the process of putting together the shopping list to upgrade the electrical system.
Have a few questions regarding the best way to interconnect the charge sources.

There a 3 battery banks
House: 420Ah
Start: 110Ah
Bow Thruster: 220Ah

Charge sources: 60Amp alternator with Adverc Regulator going to a low loss splitter to charge all three banks

Sterling Pro Digital 60 Amp Charger with 3 outputs, which will be connected to each bank.

Wind Geny D400 connected to the House bank only

270 Watts of solar is planned to be fitted, and only connected to the house bank
For the Solar, will be using a Blue Sky 3024il DUO, which will also be used to control the wind geny using the 3024 divert function.

For the house bank, which will have charge inputs from the alternator, the A/C Charger, and the Blue Sky Controller, is it OK to connect the 3 outputs to a bus bar, and then a single cable from the bus bar to the battery or the battery switch.

What about fuses/circuit breakers, plan to use surface mounted breakers, do I need to install one in each chargers output, or can I get away with using just one between the Bus Bar and the battery, and what rating of breaker?

Was thinking of fitting a circuit breaker to the Blue Sky controllers output so that if needed, I can isolate that charge source. Reason being that at time I may want to use the equalisation function of the A/C charger, and I think that if the solar controller is connected, the charge from the A/C charger will be diverted.

Is it OK to isolate the solar controller output with the panels connected?

Look forward to your good idea's

Cheers

[djmarchand]

All three charging sources will co-exist peacefully. One will probably provide more current than the others depending on its current capacity and its charging algorithm voltage setpoints.

You can tie all three charging sources to a positive terminal and then cable to the battery, but see fuse considerations below.

Remember, fuses/circuit breakers protect wire from a fault to ground that could cause a fire. All of your charging sources should be wired with big enough wire so that the source if accidently grounded couldn't harm the wire.

But the battery is another story. It can supply a huge amout of current. Check the current carrying capacity of the smallest wire among the alternator, solar panels, etc. Your solar controller will block current going to the panels from the battery so you only have to look at the size from the controller to the battery. So lets assume it is 10 gauge or the wire from the wind generator is 10 gauge which is a likely number.

Ten gauge wire can safely carry a maximum of 60 amps. So you need a 50 amp fuse or circuit breaker within a few feet of the battery. But that isn't enough to handle a high output alternator. It will trip quite often. So don't connect the alternator to the common DC+ buss as indicated above. Wire it and fuse it separately.

You probably have at least #6 wire from the alternator. #6 can carry 120 amps. So you would need a 100 amp fuse for that wire located near the battery. And since 100 amps is too much for #10 wire you either need to upgrade all to #6 which is overkill or run a #6 direct from the alternator to the battery. If you have more than a 100 amp alternator you probably need #4 wire and a 150 amp fuse.

Ancor has wire capacity and voltage drop tables. But here is a summary of current carrying capacity for fusing (not voltage drop) considerations:

10 gauge 60 amps
8 gauge 80 amps
6 gauge 120 amps
4 gauge 160 amps

FWIW the Adverc alternator regulator used to be a simple pot controlled adjustable voltage regulator. Maybe they are now modern three step regulators like Balmar's.

David

[nigel1]

Thanks David, I've got a heap of 25mm2 wire (3 AWG) which I plan to use.

Do you know if its OK to isolate the solar controller from batteries with the panels connected to the controller.

Cheers

[djmarchand]

Nigel:

#3 is good for 180 amps.

Yes solar panels will survive without harm if left open circuit. That is exactly what most controllers do when the batteries are full. But you can also do that with a switch.

David

[Target9000]

Originally Posted by nigel1

Thanks David, I've got a heap of 25mm2 wire (3 AWG) which I plan to use.

Do you know if its OK to isolate the solar controller from batteries with the panels connected to the controller.

Cheers

Do you mean to say that you want to disconnect the MPPT controller's battery connections?

If you do that it should turn the controller completely off. It would be the same things as if the battery bank went dead since the unit is actually powered by the batteries.

[nigel1]

Originally Posted by Target9000

Do you mean to say that you want to disconnect the MPPT controller's battery connections?

If you do that it should turn the controller completely off. It would be the same things as if the battery bank went dead since the unit is actually powered by the batteries.

Thats what I had hoped to do. As the solar controller will have a diversion resistors fitted, I assume that if I used the equalisation of the A/C charger, the solar controller would sense the high voltage and divert it to the resistors in the same way it controls the wind geny output.
Thoughts are if I was to use the equalisation cycle on the A/C charger, I would disconnect the solar charger and secure the wind geny blades.

[Sumner]

If you take the charging sources to a buss and then a single wire from the buss to the battery bank I'd feel fine with first putting a fuse of the right size for the wire from the buss to the batteries near the batteries. This fuse would protect the primary wire to the buss.

Then at the buss put fuses in the wires off the buss to say the alternator and the solar charge controller and other sources that match those wires close to the buss and before those sources. These fuses protect the wires to the individual circuits primarily from the high potential output from the battery if the wire or device shorts, but also from the source side. Some people put fuses at both ends in case the wire somehow contacts a ground somewhere along its length since you have a potential current source on both ends of the circuit. I don't, but that is your call.

We are using Blue Sky controllers on both boats (2512 and 3024). Blue Sky did say that it is a good idea to provide a way to isolate both sides of the controller if you want to work or remove it. We have a fuse on the battery side near the common buss as mentioned above that can be removed and then a switch that is rated to 50 amps continuous on the side to the panels.

Good luck and I think the above matches up pretty close to what David said,

Sum

[Dockhead]

Originally Posted by djmarchand

FWIW the Adverc alternator regulator used to be a simple pot controlled adjustable voltage regulator. Maybe they are now modern three step regulators like Balmar's.

David

Maybe in the Stone Age, but ever since I have been seeing them, the Adverc regulator has been an oddball device with a totally different approach to charging and certainly not pot controlled. It cycles back and forth between a quite high voltage -- something like 28.8 volts -- and a lower one, on the theory that you really need the high voltage, higher than the battery would tolerate over a long period of time without boiling, to get charge into the batteries.

If it's so great, why doesn't every do it like that? I don't know the answer to that question. But I can tell you that I get a remarkable charge into my large 420 amp/hours (x24 volts) battery bank with an Adverc regulated 110 amp (x 24v = about 2.5kW) school bus alternator. A state of charge which takes many hours to achieve with my generator and 70 amp Victron charger is done in an hour or two with the main engine and the Adverc.

Nigel, the only comment I have to your setup is why do you not combine bow thruster and house banks? You will get a lot of positive effects from that.

[nigel1]

Originally Posted by Dockhead

Maybe in the Stone Age, but ever since I have been seeing them, the Adverc regulator has been an oddball device with a totally different approach to charging and certainly not pot controlled. It cycles back and forth between a quite high voltage -- something like 28.8 volts -- and a lower one, on the theory that you really need the high voltage, higher than the battery would tolerate over a long period of time without boiling, to get charge into the batteries.

If it's so great, why doesn't every do it like that? I don't know the answer to that question. But I can tell you that I get a remarkable charge into my large 420 amp/hours (x24 volts) battery bank with an Adverc regulated 110 amp (x 24v = about 2.5kW) school bus alternator. A state of charge which takes many hours to achieve with my generator and 70 amp Victron charger is done in an hour or two with the main engine and the Adverc.

Nigel, the only comment I have to your setup is why do you not combine bow thruster and house banks? You will get a lot of positive effects from that.

Thats my view on the Adverc, and its half the price of the Balmar. To my mind, the alternator is not the main charge source.

As regarding combining the house and bow thrust banks, its the distance between them that has put me off combining them. The house bank is aft, the BT bank is in the forward cabin. Not sure of the practicalities of combining them, but if possible, its a good idea, the BT batteries get about 5 minutes of use in a year.

[goboatingnow]

Originally Posted by nigel1

Thats what I had hoped to do. As the solar controller will have a diversion resistors fitted, I assume that if I used the equalisation of the A/C charger, the solar controller would sense the high voltage and divert it to the resistors in the same way it controls the wind geny output.
Thoughts are if I was to use the equalisation cycle on the A/C charger, I would disconnect the solar charger and secure the wind geny blades.

Why diversion resistors. They're of no use with solar.

Dave

[Sumner]

Originally Posted by goboatingnow

Why diversion resistors. They're of no use with solar.

Dave

I have a feeling that the resistors are in a hot water tank and that current is diverted to them if the charge controller senses that the batteries are topped off or possibly in acceptance or float.

Just my guess,

Sum

[nigel1]

Originally Posted by goboatingnow

Why diversion resistors. They're of no use with solar.

Dave

The diversion resistor are used with the solar charger when it is used in combination with a wind geny.'
The Blue Sky 3024 Dil can be set up this way. The wind geny is connected direct to the battery, and the 3024 senses the wind geny voltage and diverts the excess voltage to the resistors.
See this link, they probably explain it better
http://www.shop.solar-wind.co.uk/aca...SB3024_DUO.pdf

Electrics is all a bit of a black art to me

[nigel1]

Originally Posted by Dockhead

Nigel, the only comment I have to your setup is why do you not combine bow thruster and house banks? You will get a lot of positive effects from that.

Is it practical to link two banks in parallel when the banks will need about 10 meters of cable to link them, and that one banks 2 x 220 Ah and the other is 2 x 110Ah.
If the experts say yes, I'll go for it, will make life a lot simpler, and gives me more usable amps

[goboatingnow]

Yeah read through the manual, but why use a diversion controller unless you can use the output.


Dave

[Dockhead]

Originally Posted by nigel1

Is it practical to link two banks in parallel when the banks will need about 10 meters of cable to link them, and that one banks 2 x 220 Ah and the other is 2 x 110Ah.
If the experts say yes, I'll go for it, will make life a lot simpler, and gives me more usable amps

There are conflicting opinions about this. Some say that this will cause a charge/discharge imbalance which will cause the world as we know it end.

Others say it works fine, especially if you use good, fat cables to connect them.

All I can say is that I have two banks which are 10 meters away from each other interconnected this way and they work fine. I regularly monitor charge imbalance and fine no measurable difference (and I'm using good instruments).

You will not only have more usable amps, but the bow thruster will burn less battery power because of reduced Peukert effect. Just make sure that the bow thruster batt is exactly the same make and model and exactly the same age as the rest.