P1000 Triple Battery?

[StewB]

Alright, after last night's outing, it has been determined:

THE CANNONS STAY!

It was only my third night running them, first one this season, and these lights are just too awesome to give up. They throw way, way out past my current lights.

I was running some tests with different combinations, keeping my eye on both voltmeters, taking some notes. As long as I don't run all of my lights together, it functions in normal range.

Me driving towards Dave at night - after sunscreen, of course. ✌️

 

[Admin]

 

[JMynes]

You may need welding goggles

 

[HBarlow]

When I was young every car and truck had a factory installed amp meter that provided instantaneous indication of what the generator was doing. Drivers relied on the meter.

A simple glance at an ammeter tells the driver immediately and accurately if the electrical system is charging or discharging.

Battery voltages change very slowly and only reveal that the system was being slowly charged or discharged.

 

[bumperm]

When I was young every car and truck had a factory installed amp meter that provided instantaneous indication of what the generator was doing. Drivers relied on the meter.

A simple glance at an ammeter tells the driver immediately and accurately if the electrical system is charging or discharging.

Battery voltages change very slowly and only reveal that the system was being slowly charged or discharged.

The voltmeter will do the very same thing, albeit with a few seconds delay (not "very slowly"). IF the alternator stops charging, voltage will quickly drop below 13 volts and continue to fall as the battery is discharging. If the alternator is charging, the voltage should be above 13.5.

The good old days I grew up in, you're correct, ammeters were common in vehicles. About as common as electrical problems which were far more prevalent back then. Still, there's good reason ammeters have fallen from common use.

 

[HBarlow]

A voltmeter is a compromise at best. Never as good as measuring current but amp meters became "too hard" with advance of automotive electrical accessories and high current draw.

 

[P1K5Dave]

So, the boys and I were drinking beer and talking about this again last night, and I had a moment of clarity that makes me want to revisit this question:

I have a dual battery system that has worked flawlessly until adding the cannons.

If I wanted to add a third, bigger deep cycle battery for just the cannons and the winch, what I would do is...

Isolate the other two from the third, meaning, don't send any current to battery 3 unless both 1 and 2 are over 13.5 volts.

That means battery 3 would probably only get charging from the stator during the day, when there is no light draw on 1 and 2. And when it came night, any cannon draw would hit battery 3, the stator wouldn't work to send it charge unless the rest of the draw was low.

Then I'd basically be running the cannons by deep cycle battery at night, and I'd only draw it so far before I shut them off.

Then I can charge it at night by plugging it in, and the stator can charge it by day when demand is low.

You can buy 3-battery isolators, somehow I have to be able to configure something to do what I outlined here.

 

[P1K5Dave]

If you need to abstract it further, imagine if I put the cannons on a full-sized deep cycle marine battery, and it wasn't tied into my Pioneer's electrical system at all.

It'd be like the battery we ran the spotlight from while spearing carp from the jon boat when I was a kid.

Then I'd be looking at a deep cycle with 11.7 amps of draw on it.

I can charge it from the stator during the day when demand is low, or charge it at home overnight.

 

[bumperm]

If I wanted to add a third, bigger deep cycle battery for just the cannons and the winch, what I would do is...

Isolate the other two from the third, meaning, don't send any current to battery 3 unless both 1 and 2 are over 13.5 volts.

You can buy 3-battery isolators, somehow I have to be able to configure something to do what I outlined here.

You can do most all of that with a another "two battery" True isolator. Just connect the new True between the current Aux battery and the 3rd battery. This system would then give primacy to the main battery, then the current Aux, and finally the 3rd battery would only get charging current from the stator when the other batteries are at an adequate state of charge.

 

[P1K5Dave]

Excellent, good thought bumperm.

Wouldn't you agree that my stator would never really work any harder on that setup?

 

[Smitty335]

Excellent, good thought bumperm.

Wouldn't you agree that my stator would never really work any harder on that setup?

Probably longer?

 

[P1K5Dave]

You mean it would work more where it previously would have rested?

 

[Smitty335]

You mean it would work more where it previously would have rested?

That's my pretzel logic. But Im no electrical genius.

 

[P1K5Dave]

That brings up a question that reveals my limitation in understanding how these systems work...

The stator and its windings are sitting there in a constant state of spin. That creates heat.

The question is whether it's always generating power, or maybe the regulator is determining requirements and is therefore increasing demand (heat) at times and letting off on demand at other times, so the windings run cooler. The latter seems more likely.

 

[bumperm]

With no load on the stator, no current flow (or minimal, such as eddy currents etc) there won't be significant heat caused by resistance in the wiring - only minimal heat from the rotating bearings and minor friction, seals etc. But the answer to your question is yes and no. If you are not running the additional electrical loads (those big A. light cannon etc.), then there would be very little extra loading of the electrical system once the batteries are charged. So my take is it will be "harder" on the charging system, but everything is relative. One nice thing is that the third battery will moderate the electrical demand to a degree, sort of averaging out the electrical load. Depending on usage patterns, you may want to charge the batteries when in storage.

 

[HBarlow]

I'm not clear on your planned use of battery isolators but If all the three batteries are ever connected together in parallel all three will equalize and all three will draw charge current from the buggy's alternator until all reach full charge.

 

[JMynes]

You can have 19 batteries all daisy chained with isolators, and let’s assume they’re all fully charged.
As soon as you turn on your high amp load the stator is supplying that current, up to its maximum capacity.
Once your load exceeds the stator’s max output the stator will continue to put out its maximum current and the ENTIRE battery bank will be depleted equally until voltage falls to kick out the weakest isolator, which may be the last one, or the first one.
At this point your stator might get a break, but when that isolator turns on again it’s right back to max current.
In the end, there is no free lunch. If your load exceeds the stator’s capacity it will be working to capacity almost constantly and your batter(ies) will be depleting.
You’re going to need that Honda generator tied down in the bed.

 

[P1K5Dave]

Im not looking for free lunch, Im looking for capacitance to be used as a buffer, to isolate demand away from the vehicle's charging system when demand is heavy.

If what you are saying here is correct, then I could make battery 3 switchable, to disconnect it from the system altogether when it's being used to run the big lights. Then I could run them until I used 50% of the battery, then shut them down.

I could then bridge the switch again when there is very little demand on the electrical system, driving around during the day. The isolators would then send current to the battery all day long, because there's plenty of available current.

And, I can charge that 3rd battery on a wall outlet at night.

So, would you agree that making it fully switchable would alleviate the load on my stator?

If so, what is the role of the isolator? Should it not look at the demand from battery #3 and deny it current to protect the batteries before it?

 

[bumperm]

You can have 19 batteries all daisy chained with isolators, and let’s assume they’re all fully charged.
As soon as you turn on your high amp load the stator is supplying that current, up to its maximum capacity.

The batteries are each connected together by two isolators; mains to aux, and then aux to 3rd bat. i.e. with engine off, a load on 3rd batt will have no effect to take either of the other batteries below 12.8 volts. If the engine is on and charging, the 3rd batt will still be handling all that load UNTIL the voltage of the Aux battery goes above 13.4 volts or so. If it does not go above 13.4 the 3rd battery gets no help. When and if it does go above 13.4, the 3rd battery will be charging and the stator will be sharing in providing current to that battery's load. The operative word here is "sharing", so the stator won't be providing all the load to the 3rd battery circuitry as the 3rd battery will be helping also. Note too, that unlike lithium batteries, lead acid batteries have a fairly high internal resistance. This is why a charger for them must provide significantly higher voltage than the batteries normal fully charged voltage of roughly 12.8 or 12.9 , often voltage from a charger can be 15 volts or so overcome the batteries interal resistance so as to force adequate charging current through when charging starts.

Once your load exceeds the stator’s max output the stator will continue to put out its maximum current and the ENTIRE battery bank will be depleted equally until voltage falls to kick out the weakest isolator, which may be the last one, or the first one.

Well, that's the right idea, but the order in which isolator will "kick out" is based on the voltage of the connected batteries. When either of an isolator's input drops to 12.8 volts it will no longer take current *from* that battery to pass it to its other connected battery. It works both ways, of course. So, the heavily drained battery will only get help from the True when the True's other battery voltage is at or above about 13.4 volts

At this point your stator might get a break, but when that isolator turns on again it’s right back to max current.
In the end, there is no free lunch. If your load exceeds the stator’s capacity it will be working to capacity almost constantly and your batter(ies) will be depleting.
You’re going to need that Honda generator tied down in the bed.

Not so. When one of the isolator's terminals goes above 13.4, it will then start providing current to its other connected battery, if that battery is low it will still be providing current to its load, so not ALL of the additional current demand is dumped on the stator, rather the load is shared to a degree. Further, the isolator will stop charging through to the low battery when it's "high" battery falls below 12.8 volts, so the large load on the 3rd battery won't cause excessive loading to any of the other batteries. The low battery, as well as its connected load, will have a variable amount of impedance that will dictate how much of current demand is passed to the stator. The stator's maximum output is limited by it's design as well as its RPM. Max output is at 5,000 rpm (IIRC). Operating at max designed and rated output should not cause premature failure.

 

[JMynes]

I would recommend you go with one of these;

But they need 24v. Not good for the Pioneer electrical system. They do put out good light, though.

 

[john790]

Well the nice thing about this post we will see how much a honda stator will take and the wiring.