adding a battery, isolator, Relay.

[OtisBlkR1]

Unfortunately this is the best forum for the question I would think and the second battery will power after market lighting.. and a winch. so, Mod's if there is a better place for my question please feel free to move this thread.

Im going to add a second battery, isolator/relay to my new UTV Kawasaki Teryx. It does operate on a 12v platform. that said, how large of a isolator/relay should I be using ? no clue what he power output of the stator on a UTV is. Cleary wont be as high as a car's alternator. #2 should both batterys be the same size ? I was intending on mounting a oversized marine grade battery under the seat of my machine for all the extra's I will be running. My Polaris Ranger had a "Polaris kit" that ran a second atv sized battery (same size as the starting battery) however when using offroad lights or pretty much anything that isolator was constantly "clicking" moving power to the second battery.

I have a plenty of experience in this subject when installing lights, winches, stereos, etc and of course and running wires.. but making sure the components are compatable is my concern if im not going to buy a pre fab kit and I am going to buy the parts separately.
Help.

 

[4wheeldog]

Originally Posted By: OtisBlkR1
Unfortunately this is the best forum for the question I would think and the second battery will power after market lighting.. and a winch. so, Mod's if there is a better place for my question please feel free to move this thread.

Im going to add a second battery, isolator/relay to my new UTV Kawasaki Teryx. It does operate on a 12v platform. that said, how large of a isolator/relay should I be using ? no clue what he power output of the stator on a UTV is. Cleary wont be as high as a car's alternator. #2 should both batterys be the same size ? I was intending on mounting a oversized marine grade battery under the seat of my machine for all the extra's I will be running. My Polaris Ranger had a "Polaris kit" that ran a second atv sized battery (same size as the starting battery) however when using offroad lights or pretty much anything that isolator was constantly "clicking" moving power to the second battery.

I have a plenty of experience in this subject when installing lights, winches, stereos, etc and of course and running wires.. but making sure the components are compatable is my concern if im not going to buy a pre fab kit and I am going to buy the parts separately.
Help.


Your buggy has a output wattage of about 450 watts. For normal use, I would figure about half that, unless you operate it near redline all the time. About 100 watts should keep the normal requirements satisfied, leaving about 125 available for sustained use. Shorter interval use (ie, winch) of the full 450 watts should not be an issue. You should size the isolator and relay for 30 amps (420watts), to my reckoning.

I see no reason for not using a marine starting battery, or even a Optima yellow top. Since the battery is isolated when not running, there is no issue with self drain down from "Battling batteries". Good luck.

 

[eljefino]

Do you have a PTO in a place where you could rig up a pulley and alternator?

I'd think pretty seriously about LED lighting just to cut the load.

You can use a ford starter relay and I'm sure RV stores would have what you want.

 

[JimPghPA]

Originally Posted By: eljefino
Do you have a PTO in a place where you could rig up a pulley and alternator?

I'd think pretty seriously about LED lighting just to cut the load.

You can use a ford starter relay and I'm sure RV stores would have what you want.


+1 on what eljefino said "I'd think pretty seriously about LED lighting just to cut the load."

If you place enough steady load on the alternator you will burn it out regardless of how big the second battery is, the alternator has to carry the steady load. And you are not going to want to use the lights for only a few minutes.

For brief large loads like the winch, you can rely on the second battery.

But for constant loads like lights being on continuously the alternator has to carry the load, so it would be very wise to minimize that load by using LED lights. And even with the LED lights don't go wild and put on so many that even with the lower load per light the total exceeds the capacity of the alternator.

If you add too much constant load you have to add a second alternator, hence the PTO question.

 

[4wheeldog]

Just to clarify, Kawasaki gives the spec of 450 watts @ 8000 RPM, which is why I suggested only using half that for a reasonable estimate of actual output.

Why Kawasaki gives alternator output figures beyond the redline of the engine, I will never understand......But they do the same thing on all their motorcycles.

 

[OtisBlkR1]

Thanks guys, No PTO, and the factory headlights are the upgraded aftermarket LED's and im going to install a stereo (no amp) and a LED light bar, the winch will of course not be of constant use, but we love to night ride so the aftermarket lights are BIG Bonus. I already have a 12inch LED bar and its amazing, I intend to buy a much larger (across the windshield) 52 inch sized lightbar next.

 

[OtisBlkR1]

I went to my local RV shop this weekend, they seemed clueless and didn't understand why I wouldn't just hook up tow battery's inline with no isolator.

 

[sciphi]

Would there be any advantages to running a marine deep-cycle battery? I'm thinking of situations where the engine would be idling but the electrical demands would be high such as winching out the machine when it gets really stuck in the mud or lighting an area for an extended period of time. The deep-cycle battery would put up with getting drawn down from a winch or extended run time of the stereo/lights far better than a starting battery.

 

[OtisBlkR1]

this a option in my plan. I ordered a battery relay/isolator today ($79.00) and am considering a deep cycle marine grade battery as my auxiliary #2 battery. the issue there is weight, were not talking about a full sized truck, its a 4 passenger UTV and weight matters. Even a 10 pound difference matters, sticking with a more leightweight 12v atv/utv lawnmower sized auxiliary #2 battery shaves a Ton of Weight.

the auxiliary battery will be used for winching (my snow plow) in the winter, and yes, sure if I get stuck while driving it in the summer. Also, I use a 20 inch LED lightbar all the time while our riding, and I will likely be adding a stereo (un-amplified) for some cruising tunes. that's pretty much it, however I don't want even the stereo and extra lights draining down on the starting battery. better safe than sorry.

 

[wrcsixeight]

What type of isolator/relay?

The diode based isolators, that have large finned heat sinks waste power and drop charging voltages.

What voltages does your kawasaki allow?

Starting batteries really degrade badly when discharged below 80% regularly. A marine battery is a dual purpose battery, and while it says deep cycle on it, a true deep cycle battery is constructed much differently.

I assume you will be running the engine when running the winch, so while true deep cycle flooded batteries have Low CCA ratings, they are not so low as to not turn the winch fast enough, and the alternator likely will take up a good portion of the load.

Some AGMs like Odyssey and Northstar have Very high CCA ratings and deep cycle ability, but when deep cycled absolutely need high recharge currents applied for long enough or battery life will suffer.
Rectangular AGMs have 25% more capacity than the Six pack spiral AGM's of the same footprint.

AGMs tend to weigh more for the same capacity as flooded/ wet batteries.

There are multitudes of ways to allow battery charging voltages to reach a secondary battery and have the batteries isolated with engine off.

If there is no need to power anything with the engine off, then I would recommend just putting a larger battery in place of the original rather than parallelling two through a relay.

Ideally, batteries which are paralleled should be the same make/size and age and condition. When they are different, they charge at different rates and discharge at different rates and the weaker of the two batteries will rapidly degrade the better of the two batteries.

If you have no need for powering anything with the engine off, I'd look into getting a larger AGM battery in place of the original instead. Odyssey and Northstar batteries have extremely low resistance and high CCA ratings, meaning they are good at holding their voltage higher under higher loads than other batteries, and when discharged they can accept huge recharging currents too. So they can be recharged quicker, if the charging source is capable of doing so.

If weight is a consideration, one larger battery will weigh less than 2 smaller batteries and the copper to join them together.

The voltages your Kawasaki allows are likely not ideal for recharging batteries. Few vehicles approach Ideal in this regard. The voltages allowed will change at different battery states of charge and alternator rpm, so one cannot just put a voltmeter on it at idle and say definitively it is 14.2 always.

You should get a clamp on Ammeter. Voltage is not really a very good tool regarding battery state of charge, but seeing the amp flow at a certain voltage is quite telling.

The LED lightbars are impressive. I've got a pair of fog light sized LED spot lights with 6 LED's each, that are as bright as my halogen 65 watt high beams getting 14.5v, and only draw ~12.5 watts.
However they are obnoxious glare machines. Anybody on the wrong side of the light is blinded.

 

[OtisBlkR1]

Im adding a "battery doctor" as the relay/isolator. the starting battery will feed off to the Battery doctor then to the aux battery, when the starting battery is full the doctor reads that and sends the charge to the aux battery. When winching or using the aux battery (short burst of power) the aux battery will handle those needs and not effect the starting battery. I stopped at a trusted electric shop last night (they rebuild alternators, starters, make cables.. you name it.. the listened to my plan and other than saying the 150amp battery doctor I ordered was overkill they said the plan was solid.

I should also not that I always hook up my trickle charger to my aux batterybefore a long day of use and after. this is the second setup ive added to a side by side UTV however the first one was pre-fabricated from Polaris. the first worked like a charm but was expensive. Im piecing this system together on my own to save some coin.

 

[OtisBlkR1]

Right now the only real question left is what battery for the aux. I like the optima red tops, however am investigating to see if they make a smaller one.

 

[meep]

1. this may be over-complex. isolators have a voltage drop--- unless you can re-route the "sense" wire for alternator output to the battery side of the isolator, you are not going to see a full charge

2. are two batts really needed? One large marine deep cycle or combo battery would probably work.

3. isolation may help to avoid really harsh loads to the alternator, but it will still have to charge the larger battery after it's been used. I might say to run the accessories off the aux batt and use a relay to join batts under normal conditions but separate during high load periods. Just let the relay latch whenever the key is on with a second switch to unlatch the battery if needed.

4. 100 watt nominal output is 8.5A or so for normal cruise-around use. Even with LED lighting, you have very low margin for headroom.

5. btw the plan sounds FUN and I totally get why you are doing it..... good stereo with a class D amp won't pull more than 2-3 amps for reasonable play. LED lamps tend to run what... 9w per 9-element unit.... so .75A per ever 9LEDs.... so make sure you don't go over-crazy. switchable levels of lighting would help....

 

[meep]

btw--- considering winch duty and all that--- I'd want to see a 50amp relay. I think at some point, especially at that size, they are called contactors or solenoids, and you'd want to make sure it was rated for continuous duty.

ANOTHER option might be to use a marine battery isolation switch! handles gobs of amps, weatherproof. you could use it to join two batts, or use an A/Both/B to choose starting and runtime duties. probably the easiest, most reliable, and electrically efficient way to go.

 

[wrcsixeight]

These automatic battery isolator devices are jokes.

Most Diode type isolators drop voltages by 0.7v.

The smart solenoid types which sense voltage are also jokes. I can have my engine battery down 50AH from full start the engine and battery voltage in seconds is above 13.3v, at which point these voltage sensing combiners would parallel the batteries. So the engine battery gets a few seconds of alternator juice alone before the batteries are paralleled.

The ones which parallel after a time delay once a certain voltage is met are a bit better, but the whole idea of topping off the starting battery, before allowing the secondary battery to see alternator charging voltages sounds great, but does not work in practice.

I happen to live on Battery power. I've observed the life cycles of many sets of batteries, watching not just voltage but amp flow at those voltages. Lots of observations, with an anmp hour counter, various loads and various charging sources. Experimentation, and verification with a hydrometer.

There is so much wrong with common perception of what Lead Acid batteries and charging systems do and how they work together and against each other, I should just quit trying to inform others.

Best thing anybody can do, is not believe any product's marketing.

"red top" says it all. Best of luck to you

 

[asand1]

Just use a golf cart or winch relay (looks like an old FORD starter relay, but is 100% duty cycle) and wire it to acc. Then as long as you are running the battery is charging.