[dish]

Which is the best type of battery for DIY waterfed pole?

Car battery or Leisure battery?

[Tim Morton]

Either a leisure battery or get a sealed lead acid battery. If you go for a sealed lead acid, make sure that it's a deep discarge type. The good thing about the sealed lead acid batteries is that they can be put in any position, upside down or on their side. The down side is that their capacity are generally smaller than leisure batteries and that they cost a lot more.
You also need a special charger for the sealed type.
If you want a sealed lead acid battery, here's where I got mine from, www.golftrolleybatteries.co.uk
Tim

[Sarah Sarill]

I have been told to use a Gel sealed leisure Battery.  Quoted £39.95 + Vat by Bristol Batteries.  Tel : 0117 9550 535.

I understand from him that the battery type is governed by the amount of daily usage.

Hes a really great guy and will fit a battery to your needs.

Sarah

[Mike George]

An ordinary car battery is a 'cranking' or 'starter' battery, and is designed to deliver a few hundred amps for a few seconds at a time, then to be re-charged quickly and kept fully charged most of the time.

A 'leisure' battery is a deep-cycle battery, designed to deliver low-ish currents (usually 5-10 amps or so) for hours at a time, and then to be re-charged over several hours to bring them back up to full charge again. If a leisure battery is used to supply a 230v inverter it might have to supply a couple of hundred amps for several minutes at a time, which really hammers the battery and the 12v cables and connections.

I don't know anything about wfp equipment but I would guess it needs a fairly low current at 12v for extended periods, so the deep-cycle battery would be best for it.

A lead battery shouldn't be discharged below about 50% of its capacity, so you need to work out the amp-hours it will have to deliver in a day, and get one or more batteries with a combined amp-hour rating of at least twice that figure.

I recommend you look up the battery specs on manufacturers' web sites to decide what you want, then shop around for the best prices for your chosen battery from specialist battery suppliers. The leisure batteries sold at caravan shops and boat chandlers are usually (in my experience) not up to the task of daily deep cycling. The ones from Halfords last well.

I think both types are available as sealed lead-acid and as gel, but I've only ever used ordinary lead-acid with removable stoppers for maintenance.

[gaza]

85amp leisure battery is a must piece of kit,most pumps are 7amp per hr,so divide 7 into the amp rate of the battery thats how many hrs life you should get out it [working hrs]

 gaza

[Tim Morton]

I have a 22Ah sealed lead acid battery, and can get a whole day's wfp'ing with it and still got power left. But i have a varistream as well so the pump is never working at full power, usually it's working at quarter power, ie a little over 1A. So if you're going to have a varistream, which I'd really recomend, you wont need quite such a big battery capacity unless you want to work for days without recharging.
Tim

[gaza]

TIM:IF THE PUMP IS 7 AMPS DRAW HOW CAN IT RUN ON 1AMP? NOT TRYING TO BE FUNNY BUT I DONT UNDERSTAND THE WORKINGS

 GAZA

[Tim Morton]

Hi Gaza, Basically when you run the pump on the full 12Volts then it will take the full amperage, ie the full 7amps. However, if you use a varistream pump controller it reduces the voltage so that the pump runs slower, pumping less water and also using less amps. That's why if you use a varisteam your battery will last whaay longer. Thats why having a varistream is so great, if you dont need 6 liters per min @ 100psi, then why make the pump work at full power using the full amps. The varistream reduces the voltage going to the pump so that it only pumps whatever water you actually want and need.
Hope this explains it, I used to be big into electronics as a hobby, now i'm into wfp!!
Tim

[gaza]

SO NOW I KNOW ;DTHAT TOLD MEEEEE, DIDNT IT, SEE WHAT A LITTLE KNOWLEDGE DOES FOR YOU. THOSE VARISTREAMS SEEM THE BEES KNEES. I HAVE SEEN THEM WORKING BUT DIDNT KNOW THEY SAVED YOUR BATTERY POWER AS WELL.
THANYOU FOR PUTTING ME STRAIT

 GAZA