Battery Protector

[Bdog1]

Anyone use on of these devises?

Automated low battery cut-off. Seems I could access a portion of my dual 31C battery's amperage for house use and if things go too far can still be protected from the dreaded no start!

 

[SoulRaven]

Absolutely, been recommending them for years. I have one on both my house battery, and my starting battery, so I can use it for power too if I choose to.

 

[Bdog1]

I would have to find a HD version. That cable looks pretty skinny for a dual bat. set-up on a diesel. Or maybe I could use it on one battery only?

It would be nice to run LEDs and a fantastic fan without being paranoid.

 

[highdesertranger]

what's the parasitic draw on that? I know that there is a parasitic draw on these automatic battery disconnects. highdesertranger

 

[Bdog1]

I was more concerned about resistance under load. If the contacts add resistance it's gonna get hot. Fast.

 

[SoulRaven]

Mine never even get warm.

Don't really know about parasitic draw, but it has to be very minimal or I would have noticed.

Prior to adding them, my house battery got charged once per week, after installing them, my house battery still got charged once per week. No noticeable difference.

Now I charge my house battery while driving and rarely use my generator.

This is my 12th year using them, and my first set of batteries lasted 6 years, and this is my 6th year on this set of $22 batteries. Prior to having these, brand new batteries would only last me 3-4 years, with these, el cheapo recycled batteries last 6 years, and I never have to worry about having a dead battery. I can go a week on my house battery, and a week on my starting battery for boondocking, and still have plenty of power to start the rig. That's about a week longer than my ice will last, so all is good.

 

[MikeRuth]

Off grid says he has used one for years and that's the best type of recommendation. Their website does not go into specifics, but there was a comment that "you may hear the gears".

From that I would conclude they are using a contact driven by a mechanical mechanism to turn the main on and off and using a very low power electronics circuit to monitor the voltage.
That could be a circuit rated in micro amps, therefore negligible to drain on the battery.
They do not post info on dual battery system but ask that you call them. I'd be a we bit concerned then if you were to have for example one protecting 4 T-105's that could offer up a couple hundred amps for several minutes on a large inverter.
It's my thought that they really made this just to protect starting batteries.

Personally I watch my house batteries daily, don't think I'd want this on them.

 

[LeeRevell]

I am hoping to devise a system to use this type of device.......

Any problems using it in conjunction with a 110VAC to 12VDC converter unit?

 

[MikeRuth]

I am hoping to devise a system to use this type of device.......    

Any problems using it in conjunction with a 110VAC to 12VDC converter unit?

Lee I'm not sure what you mean here but I'm guessing you mean to protect just the use of the inverter. If so, other than the terminals will be difficult to work with yes you could put this between the battery and the inverter only. 
Is that what your getting at? 

Mike R

 

[LeeRevell]

No, no inverter at all. But would this unit conflict with the Converter charging the batteries from shore power?

 

[Optimistic Paranoid]

Theoretically, if it breaks the connection because the battery was low, then current from the convertor couldn't reach the battery to recharge it.  UNLESS you bypassed it by running the convertor wires directly to the battery.  But if you did that, the convertor couldn't supply power to anything else until the battery came back up so the switch reset.

On second thought, the higher voltage from the convertor would probably fool the switch into resetting.

I guess you'd have to experiment with it a bit to be sure . . .

Regards
John

 

[highdesertranger]

all I was saying is there is some draw form these. a little here a little there it all adds up. highdesertranger

 

[SoulRaven]

While mine are not the same brand as the one in the picture, but rather a little silver box, mine will reset automatically as soon as a charge is added to the system.

If it cuts off the starting battery, you reset it by tapping the brake pedal then start normally.

For years I charged my house battery via a 12v DC gas generator, and the second I would start it, the protector would reset automatically. Charging by shore power should be no different.

 

[MikeRuth]

No, no inverter at all.  But would this unit conflict with the Converter charging the batteries from shore power?

No it would not interfere. 

 

[SternWake]

Regarding the product in the first post, I was curious to find out the parasitic draw.


Reading the documentation, it becomes obvious that this product is not designed to protect the van dweller.

It is more designed for the person who leaves their lights on.

Read this:

PriorityStart! is an automatic computerized on/off switching system protecting battery voltage and starting power. If battery voltage drains below 11.7 volts when engine is off, it automatically DISCONNECTS the load. The battery voltage immediately recovers.


[font=Verdana, sans-serif]To RECONNECT and START the vehicle: Just step on the brake pedal, activate the headlights, or use another accessory inside the vehicle, and starting power is automatically RECONNECTED! NO DEAD BATTERY![/font]

[font=Verdana, sans-serif]So this particular product will, after voltage has rebounded to some unknown point above 11.7v, reconnect the battery whenever another load is turned on.[/font]


[font=Verdana, sans-serif]"the battery voltage immediately recovers"  ?????  who are they freaking kidding?  Perhaps if the load is huge, the voltage will immediately rebound to some degree, but healthy warm batteries take at least an hour for Voltage to rebound 80% of what it would in 6 hours.[/font]

[font=Verdana, sans-serif]A 15 amp load, like leaving the lights on with the engine off, can take a starting medium size battery to 11.7 in about a half hour, but the voltage would rebound significantly after this significant load is removed.[/font]


[font=Verdana, sans-serif]But a smaller load, taking a battery down to 11.7, over a much longer period of time, will deplete the battery significantly more.  Voltage might only rebound to 11.8v.  If the battery is weak,/old/abused, IF the weather is super cold, then this device MIGHT NOT allow engine starting.[/font]


[font=Verdana, sans-serif]They say the positive cable is 6 awg.[/font]






[font=Verdana, sans-serif]  http://www.prioritystart.com/specs.php [/font]


[font=Verdana, sans-serif]There appears to be a lot of documentation available on this specific product.[/font]


[font=Verdana, sans-serif]But I was not able to find a parasitic load figure with a quick glance.[/font]


[font=Verdana, sans-serif]I would prefer to have a manual switch to reconnect the battery once the 11.7v disconnect is triggered, if I were to go this route regarding using the starting battery for house loads.[/font]


[font=Verdana, sans-serif]  They say all that is needed is a 0.2MV load ( loads are rated in watts or amps, not volts) to reactivate the connection to battery.[/font]


[font=Verdana, sans-serif]I just don't see enough protection for engine restarting with this particular device.  Starting batteries do not handle many cycles below 80%, so this product might be great for the Soccer mom who left her lights on for 2 hours, but for the Van dweller pulling the battery down much slower, might find their lights go out, nothing works, phone can't charge, and the engine still does not start.[/font]



[font=Verdana, sans-serif]At which point they'd need to go disconnect the product, and connect battery directly, just to recharge the phone and call for a jumpstart, In a blizzard  with 65MPH winds with hungry packs of Wolves,  Coyotes and grizzly/polar bear hybrids rocking the car back and forth.[/font]


[font=Verdana, sans-serif]Dont forget the Locusts[/font]
[font=Verdana, sans-serif][/font]

 

[akrvbob]

Oh no, not the locusts again!!!!!!!!!!!!!!!!!  
Bob

 

[karl]

I found another brand, without the pretty colors and promotional propaganda, and with a dash mount manual reset. (I like buttons and knobs'-) )
http://www.amazon.com/Battery-Prog-...bs_auto_1?ie=UTF8&refRID=1YS2F2YAMWW4CPK42Q3Z
Seems most reviewers had purchased the units instead of searching out and repairing a phantom draw that was draining the battery. I could see using one of these on a start battery that sits for days at a time....or for soccer mom's and (ahem)old forgetful carpenters....but not on a mobile abode to use instead of an isolated, dedicated house battery.

I'm with Sternwake on this one, except that I fear my force field going dead, and the Reptilians coming for me more than locusts.

 

[LeeRevell]

Oh no, not the locusts again!!!!!!!!!!!!!!!!!  
Bob

Locusts should be no problem unless you are in a Trabant.  Dang those organic bodies!  

I learned something by reading about this device.  Battery ISOLATOR vs. SEPARATOR.  Different critters.  I think my needs would be met best by the Battery Separator.  Found two I am looking at, first is 100A, second is 200A.  If I go with a couple 120AH 12V house batteries, I am assuming the 200A Separator would be best?

 

[SternWake]

There are multiple methods for allowing alternators to charge house batteries, and protect engine battery with engine off.

If the isolator device has finned heat sinks, avoid it, as it is a diode based device that drops charging voltage( and thus charging current) too much.
Solenoids come in dumb and smart varieties. Smart ones are time delayed, or are voltage controlled or perhaps both.
Some Are called automatic charge relays.

The Blue Seas ACR is a quality unit, but the simple solenoid is the cheapest.

I use 3 manual switches because I want complete control of where current flows to and from.

All methods have some pos and negs.
Generally one wants higher amperage rated models, as the lugs will accept thicker cabling and bigger ring terminals, and thicker cabling is necessary to get adequate amperage to pass from alternator into batteries when they are low. 6awg should be considered the minimum thickness for this task.

Also higher amperage rated models have larger contacts that are less prone to heating voltage drop and early failure.

Even if your alternator will never pass 100 amps to the house batteries, a 200 amp isolation device will last longer and cause less voltage drop than a 100 amp version, and is worth the extra $. Save money elsewhere.

 

[LeeRevell]

SW, thanks! I think this answers my questions adequately.