Wiring Two Machines Up to Same Battery

HighTide

HighTide

New member
I have 2 questions regarding battery hookups:

1) Can you use the same deep cycle marine battery to to hook up both a hot water and a cold water unit? Both units are Vangaurd 18 hp with 20-amp recharging systems. For now, only one of the units will be running at a time but that may change soon should I get some of these larger jobs I am bidding on.

2) Can you use the same deep cycle marine battery to hook up a cold water unit and a 12-volt roof pump? Will the 20-amp recharging system be able to recharge the battery after a long day (or two) of roof cleaning? If I ever run the battery to low to start the engine, I can always pull start it. If the battery is too low to start engine, how many hours would you have to run the PW to fully recharge the battery?

Just thinking of any options as I rebuild my hot water skid trailer to add a cold water unit and a likely future 12-volt roof system and I have two new batteries. Having 3 batteries is fine, one for each setup, but if I can save a little space and money by just using two for now... Thanks!
 
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Interesting questions! We've run 3 machines, work lights, 12v exhaust fans, chargers (18v battery packs for cordless tools), and radios off of a 4 battery bank. We used the set up for about 4 months w/ no problems. I think the batteries all still work (around 3 years of medium use). Our heaters were all 110v. I never really considered how the multiple chargers would effect the batteries. We had them set up parallel circuit, but I don't know why or if it matters. Honestly, I can install new windows in a home or car, throw an egg off a 5 story building and land it safely, even file your taxes in 3 different countries and 3 different languages (but except English, languages don't match the countries), but I can't tell you why ac makes me piss myself and dc just tickles my tongue... Electricity is one of few things I'm just about entirely ignorant about!
 
BlueBliss said:
.. I can install new windows in a home or car, throw an egg off a 5 story building and land it safely, even file your taxes in 3 different countries and 3 different languages (but except English, languages don't match the countries), but I can't tell you why ac makes me piss myself and dc just tickles my tongue... Electricity is one of few things I'm just about entirely ignorant about!
Click to expand...

LOL !!!!!!!!!!!!!!
Come to my troubleshooting class,
and be careful to check battery condition weekly,
especially connections and fuses..
everything is fused, right ?

HighTide David..
3 times the battery is better than 3 cheap batteries..
go with a gel-cell, fuse everything,
and stainless steel hardware and the greasy-spray are the next steps in bulletproofing.

All of you..
avoid using the truck's battery to run your systems.
And.. don't go over 25 amp fuses on 20 amp charging systems,
unless you want to call me about upgrading connections from standard.
 
On the truck units we run one or two pressure washers off the truck battery. I never even thought about the charging rate with two machines running, but we've been doing it for about three years with no problems and still on the same battery in the one truck.
 
if I remember right.. the fuse between the truck's battery and the pressure washer starter..
should be 40 amp rated, but..
add a manual cut-off switch isolating the truck's system when driving..
I stock'em.
affordable insurance is good :{)
 
Good question David, had the same questions with my dual motors charging a single battery , I just had them put two batteries, but Jerry's the man he is an electrical engineer.


Kyle I remember my cousin telling me he had to demonstare that 5 story building and egg stunt at his second interview for an oil drilling company, years ago.
 
We have been running two systems per battery for years. We use large batteries 8d's. They are for tractor trailers, busses and heavy equipment. We also run our 12vt roof pumps from that as well. Yes all fused and never had a problem. We have 3 rigs set up this way. works out well. Just my 2 cents.
 
Sirocco Jerry said:
LOL !!!!!!!!!!!!!!
Come to my troubleshooting class,
and be careful to check battery condition weekly,
especially connections and fuses..
everything is fused, right ?
Click to expand...

I'm trying to get to one of your troubleshooting classes! You giving one in Tampa (any idea when Tampa happens, yet)? Our battery bank setup was only temporary while we were rebuilding 2 transmissions. Everything had a fuse except the exhaust fans. Luckily we never had any problems. We use all interstate batteries, or the brand they sell for smaller batteries. We've considered gel cell. We also considered lithium. They were expensive, put apparently charge a lot quicker and are MUCH LIGHTER!!
 
innovativewash said:
We have been running two systems per battery for years. We use large batteries 8d's. They are for tractor trailers, busses and heavy equipment. We also run our 12vt roof pumps from that as well. Yes all fused and never had a problem. We have 3 rigs set up this way. works out well. Just my 2 cents.
Click to expand...


That reminds me... I used to have a battery like that in my ski boat, so I didn't have to worry about running down the battery with the stereo system. I wound up blowing up the bass tube, so the big battery isnt needed anymore. Plus, I think those days are over anyways!

On our trailer we have two machines running off of the same big trolling motor battery. We've also got a machine and a 12 volt heater sharing another.

At one time I had a 12 volt pump wired into one of them and the machines kept it charged fine.
 
I have always heard from mechanics that the Interstate batteries are the best out there.

In my Hotsy 12 volt hot water pressure washer, the rig is over 8 years old and the same Interstate battery still going strong.
 
The cold water unit will have no draw except at startup, the hot water unit will have a draw at startup and when the burner is running. as long as the overall draw is less than the charging rate you will be fine. I would not run the 12V pump and the burner at the same time though without a relay installed to protect the burner from the surges. As a general rule it should work fine but be sure to fuse the connections.
 
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