MST-A600 12V Lead Acid Battery Tester

I'm just wondering whether any of you usenet monkeys have used the above unit and whether you can recommend it?!! I've tried to find some reviews on the internet, but can't find any independent ones. I'm after a battery analyzer that can do AH(amp hours) reading as well(not just Cold Cranking Amps, etc) Apparently the above model can do that.

Reply to
Damian
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How does it claim to do that? All the stuff I've read about requires you to enter the claimed AmpHrs, then do settings as you use it. Okay if you start with a new battery, but chancy if trying to work with old one.

Reply to
news13

CCA is a short term reading, the battery can provide it or not.

With Amp/Ht, the capacitry varies with discharge rates. commonly batteries are listed at the 20 hour discharge capacity C/20, which inflates the value. If your rate is C/5, then you won't get the same output.

You be better reading V(voltage) & s Hg(? specific Gravity) and consulting some of the various chart for that particular brand/model looking for a multi point match on one of the charts.

Most DD batteries give good Open Circuit voltage when they are freshly charged, but allow them to sit for 24 hours and you get a truer reading.

One method is using a volt meter and an ammeter and just take periodic readings as it discharges into a known load.

The other method is for when you can not sit there for hours, is to rig up something like Voltage cut off that provides power to a known load and timer. recharge at the end of each voltage cut off. Not as quick, but it has the benefit that it is doing a more thorough test.

My 2c is that bottom line I want it to do something and the easiest way is to set it to doing as close to that as I can and just observe the result. I've never had much luck mixing various used batteries for heavy loads. I just tend to dig deep and buy new stuff for critical needs like the camp fridge/freezer and use unknowns for lighting, or powering the lap top or old incaandescent flood lights.

Reply to
news13

That doesn't sound like a good brand of battery to me. OTOH, I tend to buy the Trojan brand. Oh, all wet cells.

The advice I was given that max current for SLA & AGM is C/20 and for wet cells, which is what I buy, is C/10 or you are shortening your battery life/cycles/capacity/?

Yes, I know they claim fantastic performance for AGM these days, but the spruiker usually makes money by selling them and is wanting me to chance my money. ........................

I just buy known good brands from a known good sources. My 2c is that if it is too good to be true, then it is.

Then you don't have the correct capacity in batteries. One of the more recent claims for well known brand of AGM was they could be completely recharged from flat in four hours. They could, but a quick look at their model charts and it showed that this reduced the number of cycles from ~1,500 to ~500. Nasty.

In 2006, $2,100 for four x 6V 225 amp hour batteries.

I don't buy from retail shops as such. I looked around the local industrial area and the company I've always purchased from was into industrial batteries for forklifts and such. Usually my batteries are an order in as he doesn't get many demands for them.

Last time I was there I noticed that he was selling the exact same chinese SLAs as does the farting chickens place. No idea of the price comparison to their retail as I get the monthly latest crap flyer from farting chickens and FC "wholesale" are cheaper.

Understandable. My 2c is to evaluate the seller. If you're not sure, don't buy. Also make sure they come with a warranty or your just buying junk.

Reply to
news13

Estimate based on internal resistance? If the internal resistance has grown to 1 ohm, then you can only get

12Amps max from a starter batter. Basic V=IR transformation calc.
Reply to
news13

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