Battery management: Blue Sea ACR vs Pro Split R zero voltage drop isolator

[bruceb58]

Re: Battery management: Blue Sea ACR vs Pro Split R zero voltage drop isolator

You should do that and let us know how it turns out.

I would have designed it differently. No reason not to have it default connect solid to the start battery and then control when the others connect.

 

[sam am I]

Re: Battery management: Blue Sea ACR vs Pro Split R zero voltage drop isolator

For you Bruce..the world!!

 

[sam am I]

Re: Battery management: Blue Sea ACR vs Pro Split R zero voltage drop isolator

Following up here FWIW........Got it in the boat finally.



It appears they use relay/s as well(I can hear it/them clicking) where I believe a NC contact when not powered(and powered of course), is connecting "alt" input directly to "start batt" output.....zero ohms between the two. Upon power up, it does just what they claim..........routes charge currents where needed.

Seems the hierarchy if all thing are equal'ish is to make sure start batt. is up to snuff first while not having either #2 batt or #3 batt in the charge circuit. Then it will parallel #2 batt. with start batt. once start batt. is up to snuff, then it will parallel #3 batt with start batt. and #2 batt once #2 batt is up to snuff.

As a "back feed" test, I shut the motor off and I discharged #3 batt for about 1/2hr. with a live well pump and all the lights on the boat. Upon start up, it did as described above BUT, once it knew start batt and #2 batt where good to go, It routed all the charge current to only #3 batt by switching start batt and #2 batt totally out of circuit. I like this,.......not paralleling your charged batt/s w the dis-charged batt/s idea, pretty slick I must say. Just route charge current/s where needed.

I repeated this test but with discharging #2 batt this time and it did basically the same except it switched out(took it offline) start batt, and never got to #3 batt. and just routed the charge current to #2 batt. Then it paralleled #3 batt. with #2 batt, waited till the those two were up to snuff, then brought start batt back online....cool eh?

It appears to be looking at the depth of discharge in each batt to determine if it will need to take any charged batt/s offline as soon as it can so as limit/not to be dumping/discharging your good batt/s into the discharged batt/s.......slick!!

So far so good.....except, The Honda!!! Seems I over looked a small detail here. When I start the Honda and run it just by itself, there is no "ig" on signal to turn on the unit unless I turn the key on........doh!!!

Might have to "OR" the ig on signal w the honda's b+ out..........hmmmmm.(5/1, Edited above(again 5/8, Rev B, relay 1) drawing to accommodate this, added D1 and D2)

Added 5/12 Rev C, a single wire from "alt in" to run to helm voltmeter so when unit switches to just charging Batt #2 or #3("backfeed" mode) this will now be reflected at helm's Voltmeter, otherwise I was only able to monitor start batts and/or the normal parallel'd w start batt. voltages.

Initial tests w relay and diodes for Honda to turn on unit and charge batts with Ig switch/Merc off works well. Have to use relay in this schema due to "alt in and "start batt" terminals being tied together w unit off...........Charging methods appeared fine/normal, it even back feed for a bit on batt #2....Honda took unit through each battery in turn and had them all paralleled.

I'll try to get a data logger on it in the next week or so and plot a few graphs.........

 

[bruceb58]

Re: Battery management: Blue Sea ACR vs Pro Split R zero voltage drop isolator

Can't believe they use relays! LOL...after all the talk!!!!!

 

[sam am I]

Re: Battery management: Blue Sea ACR vs Pro Split R zero voltage drop isolator

They claim "FET based Isolator" :noidea: ........

I haven't opened it yet so not sure if all the switching is all relays thou, but I do hear a few in there...........It's all in the pitch I suppose. I'd say it's more a hybrid at this point.

But thinking about it and now having a bit better understanding of the way they have designed it(wrong or right) through use, not all speculations and guess work, I re-guess in the start-up they sorta had too I reckon based the algorithm taking the start batt offline to route current to the other batts at times.

Given this, I suppose to ensure that if the thing took a major dump and attempting to build in some sorts of a fail safe when and if, a relay would always (unless the relay pukes) ensure the alt. was hard wired'ish to the start batt.

My alt is only 40 Amps max so any drop at that current and the low Ron(Relay or FET) will be way small but I'll measure it and post it anyway. They claim 0.1V at 160 Amps thou. 0.000625Ω's. Hmmmmm, that's mighty mighty low for either I'd say. Not so sure, we'll see eh?

I had hooked this thing up in the garage this winter to one of my 2AMP battery maintainers to all three of my boat batts, two being deeps and one start, it worked pretty cool current steering with only having 2 amps of current to work with between this hefty'ish load of three batts but, it eventually had brought them all up one at a time and then had put them all in parallel and was at the float charge.

 

[bruceb58]

Re: Battery management: Blue Sea ACR vs Pro Split R zero voltage drop isolator

Given this, I suppose to ensure that if the thing took a major dump and attempting to build in some sorts of a fail safe when and if, a relay would always (unless the relay pukes) ensure the alt. was hard wired'ish to the start batt.

LOL...you mean like I said way back in post #15?

It's very funny how this thread went. What happened to your solid state relays and passive load resistor?

 

[bruceb58]

Re: Battery management: Blue Sea ACR vs Pro Split R zero voltage drop isolator

I hope one of the inputs to that box forces any combining of batteries off because those cables going to that box are pretty light gauge.

 

[sam am I]

Re: Battery management: Blue Sea ACR vs Pro Split R zero voltage drop isolator

LOL...you mean like I said way back in post #15?

It's very funny how this thread went. What happened to your solid state relays and passive load resistor?

Very funny? I'm curious, how so?

 

[jhebert]

Re: Battery management: Blue Sea ACR vs Pro Split R zero voltage drop isolator

I hope one of the inputs to that box forces any combining of batteries off because those cables going to that box are pretty light gauge.

The same thought occurred to me. Some of the wiring looks like low-voltage speaker wire. The translucent red insulation on the battery cables is quite interesting.

But whether the installation practices will pass Bruce's muster--or conform to ABYC recommendations--I still found the mention of the Pro Split R zero-voltage drop isolator to be interesting, and I look forward to hearing more reports about its operation from someone who has actually installed it and is using it. Reports such as those are generally more valuable than speculation from people who have not even seen the device in person, let alone used it or tested it. I hope Sam gives us more comments on it.

 

[sam am I]

Re: Battery management: Blue Sea ACR vs Pro Split R zero voltage drop isolator

speculation from people who have not even seen the device in person, let alone used it or tested it.

That tends to happen with some here more than others I've noticed.........Some, I've noticed, tend to also follow a blog mantra that others just highly value their opinions(and should just go with) on matters as these folks tend to just seem to overly value their own opinions ........Strange that to live in such a little world as that. Perhaps its just a post counter thing, demographics and certain personality types?

The same thought occurred to me. Some of the wiring looks like low-voltage speaker wire. The translucent red insulation on the battery cables is quite interesting.

But whether the installation practices will pass Bruce's muster--or conform to ABYC recommendations--I still found the mention of the Pro Split R zero-voltage drop isolator to be interesting, and I look forward to hearing more reports about its operation from someone who has actually installed it and is using it. Reports such as those are generally more valuable than speculation from people who have not even seen the device in person, let alone used it or tested it. I hope Sam gives us more comments on it.

At any rate.....The red stuff is actually some spare oxygen free 8AWG tinned 105C, oil/water resistant yada yada power wire I just sub'd in for two of the short run batts. I ran out of the 6AWG black "$marine$ grade" stuff, had to order/get a loan for more and will pop some ends on it later. The low current(sense, ig and gnd) is also oxygen free tinned type as well, that probably being the more speaker'ish, yes......

I had a date with some fish this AM, got in a bit of a hurry yesterday with it but, wanted it up and running for a prelim run and testing when I went out this morn.....

The crux here is it ran very well and did its job, no complaints yet...each time I fired up after trolling or whatever and using various levels of batt power with misc loads on each ISO'd batt, it just cycles through all the batts(I could see it sequencing through all the batts on the dash analog volt meter). and had them put in parallel like clock work. It's not quite buttoned up as you might have noticed....But, at this point, I'm very pleased with its performance......It even caught fish

As stated earlier, I plan to put a data logger on it and plot some graphs hopefully in the next week or so.......Fishing always comes first eh?

 

[sam am I]

Re: Battery management: Blue Sea ACR vs Pro Split R zero voltage drop isolator

Was able to pull some data off this thing today, turned on 750 Watt inverter powering laptop on batt #2 and constant type loads I had including a live well pump, all lights on the boat, fan, radio etc on batt #3

0-750'ish = Dock down lake to the fishing hole,

750'ish to 1400'ish = quick bit of fishing stopping and starting motor,

1400'ish to 2200'ish = run back to dock.












Seems lacking a wee bit of hysteresis.......hmmmm.

 

[jhebert]

Re: Battery management: Blue Sea ACR vs Pro Split R zero voltage drop isolator

...The red stuff is actually some spare oxygen free 8-AWG tinned 105-C, oil-water resistant ...wire...

It sounds expensive, but it looks cool. I have never bought in with the Hi-Fi clique that insists oxygen-free copper wire can make an audible difference.

 

[sam am I]

Re: Battery management: Blue Sea ACR vs Pro Split R zero voltage drop isolator

Yes, it is waaaay too pricey for me, HI-Fi or not. My kid acquired it somehow and just left it in the garage a few yrs back............I'm cheap, save everything and it fit the need.

Besides, I just like my old AM/FM stock "marine" stereo tuned to classic rock with lots of oxygen, works well enough for me and every once in a while, my AM band comes in handy as a lightning detector too

 

[sam am I]

Re: Battery management: Blue Sea ACR vs Pro Split R zero voltage drop isolator

Went out for about 2 hours, wanted to see if I could track down the oscillations, seem gone now, IDK..........Loads again were just the inverter on batt #2 powering the lap top and misc light'ish house loads(fan, fish finder, radio) on batt #3 until it got dark'ish(4000'ish) then I had turned on all the lights(running, deck, cabin) and had turned on a pump on(5500'ish) with few smallies in the live well.




Had a bit of a struggle getting motor started 5325-5375

 

[Auger01]

Re: Battery management: Blue Sea ACR vs Pro Split R zero voltage drop isolator

Looks like in the graph in post 31 that the oscillations were caused by it trying to parallel batt2 and the voltage would drop below 13 and it would unparallel batt2. When it finally got battery 2 paralleld up and it held 13ish volts, then it started working on battery 3.

 

[sam am I]

Re: Battery management: Blue Sea ACR vs Pro Split R zero voltage drop isolator

Looks like in the graph in post 31 that the oscillations were caused by it trying to parallel batt2 and the voltage would drop below 13 and it would unparallel batt2. When it finally got battery 2 paralleld up and it held 13ish volts, then it started working on battery 3.

Yup, the alt was dropping out'ish.

I didn't have a RPM channel recording(doh!!) to confirm this theory but, I was idling(casting/fishing, stopping and starting the motor as I recall and by the looks of the ignition signal) which makes sense. The alt was able to source just enough current to pull it up and switch it over and held it just for a tad but then was dropping out allowing the voltage to drop back below the upper thresholds voltage(Vut) until I booked it at 1670'ish which brought the alt source current up.

Tried to re-create but no luck in #34 but I might not have taken the batt as low and idled enough.....I'll try to dis-charge it further and idle more perhaps in a few days,

The fix I'm thinking thou?...More hysteresis(not gonna happen unless I can get in and edit their code as I believe their running microchip, so assembly or C ) and/or less idling(#34 plots implies this)for a 40 AMP at 5K alt...good eye balling btw ty.

 

[sam am I]

Re: Battery management: Blue Sea ACR vs Pro Split R zero voltage drop isolator

...

 

[UncleWillie]

Re: Battery management: Blue Sea ACR vs Pro Split R zero voltage drop isolator

I am thinking that Batt#2 is either a little weak or undersized for the Load.
It goes from 12.6 down to 12.2 in ~15 minutes(1500-2500). It will be in the 11's and nearly dead in about 30 minutes.
When it starts charging it really strains the alternator.

What Data Logger are you using?

 

[sam am I]

Re: Battery management: Blue Sea ACR vs Pro Split R zero voltage drop isolator

I am thinking that Batt#2 is either a little weak or undersized for the Load.
It goes from 12.6 down to 12.2 in ~15 minutes(1500-2500). It will be in the 11's and nearly dead in about 30 minutes.
When it starts charging it really strains the alternator.

What Data Logger are you using?

Noooooooo........don't say that, I just bought it(two actually) last year. Both #2 and #3 are new last year and are Costco Marine Deep Cycles......hmmmm, good catch thou.

But I agree, it was going pretty fast. I was actually watching/noting that between beers errrr, fish during #34's recording and was thinking sorta the same. You know, in the linear world anyway!! BUT, looks sorta to flatten out(12.25V, 50%?) at 3400'ish in #34 thou eh? dv/dt definitely changed there abouts...... Not sure how much the load current backed off there if at all thou.........The inverter was still on but, the laptop's batt. might have topped/backed off by then.......hmmm, certainly could be a bit weak loosing it's fisrt 50% at the rate it did thou.

#2 was switched out(switches on positions #1 and #3 respectively, see schematic) BUT, it has the load tied directly to the batt(not shown) and is that cheapy'ish (maybe 80% efficient +/- 100% :smash750 watt inverter running this laptop and it's power adapter with the USB DAQ. I have a 50 AMP inline breaker(12V side of inverter of course) there, so it wasn't drawing more than that but, I should measure it and do a little figuring. If it's weak, Costco will replace it for free, they're real good about that, and I like free!!!

#2 batt however(in the nearer future I hope) in theory is actually intended for my "pivot spare" to only be used in either system should I need it and isn't suppose to be being used...........lol. If its sorta toasty already, good to know now eh?

If it turns out this is the nature of the beasty and I end up needing more inverting, although not too likely thou, but maybe one of the on-demand coffee makers for fall fishing, using batt. #3(same type batt as #2), I'll just pop #2 in parallel w #3


I need to test the Ig. signal "OR'ing" with the Honda still and I might just get waaaaaaaaaaay too much time on my hands and grab a RPM channel and setup 3 additional channels with differential inputs and log current In/out of each batt. across a foot or two of wire.:facepalm:

I suppose then with this test and knowing battery condition[weak(I will replace it) or not] and instantaneous current draws, it might show that during idling and a higher demand for current w my wimpy 40 AMPs @5K, It's just my alt. and I will know what too expect....and when.

USB-Based, 22-Bit Data Acquisition Module - Measurement Computing

It's no HP or National and not a speed/res demon but, it works nice for a portable USB jobby and my home'ish type needs.

It automagically dumps the data into a excel spreadsheet(comes as a plug-in), I then import the data into Matlab(just my personal pref for editing/plotting) for plots and to do a tad bit of filtering and/or sensor cal/line equation fitting if needed.

 

[sam am I]

Re: Battery management: Blue Sea ACR vs Pro Split R zero voltage drop isolator

Now you have me paranoid U.W. and short of running down to the boat with my turkey baster, I'm being lazy today, spot me on this "Big.W."



"RC is 140", RC is defined then as 140 Minutes @ a 25 Amp discharge rate.

Also then, 140 min * 60 = 8400 Sec's @ 25 amps

charge(q) in coulombs = current(i) * time(t)

or

q=i*t

and since time(t) = 8400 sec's and current(i) = 25 amps, the charge in the battery = 25 amps * 8400 sec's or 210000 amp sec's(as)

or 210000 coulombs(q)........if you like

To convert sec to hours, divide by 3600 (60 *60)

so amp sec(as) converted to amp hours(ah) = as/3600

therefor, 210000as/3600 = *58.33ah (#1)

*(Gross rule of thumb in the hood is RC/2 is approx. equal to amp hour(ah), so this checks)

My laptop power supply says 1.5 amps(which I'll use since it was running fairly warm and auto temp sensing/proportional cooling fan in the inverter was whirling away), so 120V * 1.5 amps = 180 Watts

My inverter is 80% efficient(on a good day), so 1/.8 = 1.25

It then requires approx 225 Watts(180*1.25) @ 12 Volts

225 Watts/12 Volts = 18.75 Amps (#2)

From #1 and #2,

58.33 ah/18.75 Amps = 3.1

My discharge rate is about C/3.1

Then using.....



which is taking into account the intrinsic losses during discharge of lead acid's using the Peukert Law, and IF(it should be) my battery follows this C/3 curve, based on what we see, I'm thinking the batt. is still okay?

i.e., at my discharge rate of C/3 and when I eventually arrived @ 11.75V(⌂t = ?, hard to use a linear approx. since it behaves non-linear like my ex), I still should have 90%'ish remaining (down to 9.5 volts anyway):der: