calling all BATTERY EXPERTS

[lovetoreef]

I am planning on using this inverter/charger to provide back up power for my return pump (tunze silence pump - uses 40 watts) ...
http://www.tripplite.com/en/products/model.cfm?txtSeriesID=314&EID=14617&txtModelID=2938


i am planning on using a deep cycle marine battery to power it, should i go with 2 100 AH batteries or one 200 AH battery?? obviously the cost goes up with the higher amperage battery and you lose some redundancy with only one battery, but it saves space - any suggestions?

 

[lovetoreef]

anyone??

 

[MrSandman]

Assuming that the specs' of the 2 batteries are identical (except for capacity) I don't think it makes much of a difference performance-wise.

The cost vs. size benefit is really your call.

 

[stugray]

One thing to caution you about: The spec says "PWM sine wave output voltage of 120 V A"

It doesnt mention "TRUE-SINE" which is an indicator of high quality output.

It might not drive AC pumps well.

You would have to ask the manufacturer.

Stu

 

[lovetoreef]

hmm, good point on the quality of outpu, i thought this was one that would give a true-sine wave ... i will have to contact the manufacturer - thanks.

 

[jcabatu]

this is very nice and a little on the overkill for only a 1/3rd of an amp. Go with 1-100amp hour battery and see what time you get out of it. if it meets your expectations, then you can decide if you should buy a second 100amp/hour battery. FWIW-don't "test" this too many times as you will ruin your battery.

 

[jcabatu]

I believe it is due to the fact that the power is being inverted that you will not have a true sine wave. and when treated like a UPS, it goes AC-DC-AC to motor.

 

[lovetoreef]

so does that mean it is not possible to obtain a ture sine wave to run the pump??

 

[dzhuo]

Have you consider this?

BRS backup battery

Might be easier and cheaper?

 

[lovetoreef]

my concern with that is not being able to add batteries to it to extend the battery life if i need to

 

[Mike31154]

<a href=showthread.php?s=&postid=15507545#post15507545 target=_blank>Originally posted</a> by lovetoreef
so does that mean it is not possible to obtain a ture sine wave to run the pump??

True sine wave inverters are available, they tend to be 3 times the price of modified sine wave inverters. The link you provided for Tripplite didn't work for me, but if the price is less than $300, I suspect the unit uses a modified sine wave inverter.

 

[lovetoreef]

mike -

thanks - you are right - i have found a true sine wave inverter, but, as you said, they run around $1000 for an entry unit ... taking into consideration that this is an emergency type of situation where they will rarely be running on the inverter, will i do damage to the pump running it on a modified sine wave??

also, i found a fleet inverter/charger from an ambulance company - xantrex makes it - it appears to be a superior product to the one tripplite offers

 

[Mike31154]

No idea whether your pump will be damaged with a modified sine wave inverter. Short term it may run ok, it may not. If it does run, it will not do so efficiently and battery capacity will be diminished as well. Is it worth the risk to find out??

Before the day of the solid state inverter, there was an animal called the 'mechanical' rotary inverter, or motor generator if you will. Might be able to find one at your local surplus store. But these won't come with any automatic switching technology to sense a power loss, plus they're noisy and maintenance intensive, bearings, brushes etc. Might as well invest in a normal engine driven generator then, virtually all of these produce a true sine wave AC signal.

For the $1000 plus you're looking at for a modern solid state true sine wave inverter, you could get two VorTech MP40W propeller pumps with battery backups. Your return pump would get a break during power outages and your tank should be safe.

 

[lovetoreef]

hmm, good point ... i will have to re-evaluate this plan as i go - thanks.

 

[Bruno3047]

Here's what you need:

http://www.theinverterstore.com/the-inverter-store-product.php?model=pwric150012s

http://www.sears.com/shc/s/p_10153_...e=Batteries+&+Chargers&sName=Marine+Batteries

Make sure that whatever battery you buy, it's AGM (Absorbed Glass Mat) construction.

 

[Mike31154]

That's a nice looking inverter, with transfer switch, battery charger and all. Still, close to $600, then you need the batteries, fuses, cables. 1500watts isn't bad, but still pricey for that amount of power.

 

[lovetoreef]

well, still not 100% sold yet - i actually was able to purchase an inverter and charger combination that was from an ambulance ... it is everything i want but with a modified sine wave instead of a true sine wave ... it "only" cost me 140 shipped, but of course, i am still going to have to purchase the battery.

the issue at heart with the vortech setup is as follows ... i have owned 3 of them ... 2 of them purchased new - i was able to get them installed and working for a while, then, they would start to slip and get out of alignment ... of course, i went through customer service, and while they are a wonderful product, just not for me... so, i would love to try to find an alternative. i suppose i can try this inverter out on a pump and see how it responds and go from there.

 

[lovetoreef]

why is it so important to use a absorbed gel mat battery?? vs. a sealed lead acid battery??

 

[dvanacker]

The absorbed glass mat will probably mean that instead of the liquid acid being wet and floating around it is aborbed into glass mats (similar to insulation I assume). Means a more rugid battery and if it breaks....no dangerous mess.

 

[lovetoreef]

hmm, i could see how that would be helpful in a boat or rv, but, in this situation, the battery will be not be knocked around or anything along those lines ... any other reasons?? Thanks.