Battery condition indicator?

[raymondh]

This is being pushed on a motorhome furum 

https://www.amazon.co.uk/dp/B07C5P5QQL?ref_=pe_3187911_248764861_302_E_DDE_dt_1

Has anyone fitted one ?

Ray

[BruceinSanity]

It’s basically a fancy amp-hours counter, isn’t it, with all the pluses and minuses of those that we’ve discussed so many times before. Presumably the measuring module contains a shunt.

[WotEver]

Yeah, there are dozens of these on eBay. Some are wired, some are wireless, some only have 100A shunts, some more, etc etc. 

[Tony Brooks]

and some, I understand, are shuntless and use Hall effect to assess the current. If it is Hall effect I would not want to trust low amp readings and as it is certainly of Far Eastern origin I would not be too happy with the likely quality and performance unless it had been quality controlled by a larger UK firm.

[peterboat]

2 minutes ago, Tony Brooks said:

and some, I understand, are shuntless and use Hall effect to assess the current. If it is Hall effect I would not want to trust low amp readings and as it is certainly of Far Eastern origin I would not be too happy with the likely quality and performance unless it had been quality controlled by a larger UK firm.

You are right Tony ,I have a midnite solar controller, internal shunt I would think, a BMV external shunt and a cheap far east meter for my electric motor, all three give similar but different readings. The midnight seems to be closest Checked using a calibrated meter the other two are a couple of percent out, its the same for volt readings or amps in. The Midnite cant measure amps out so the other two are again a couple of percent out to the calibrated meter.

The reason I know all this is you have to correct the midnite controller when you fit it, so I borrowed the meter from a local panel builder I know

[Tony Brooks]

I know because I fitted a Far Eastern 50mm round digital voltmeter that consistently indicates 0.2 to 0.3 volt low and there is no calibration device. Not so good for assessing battery state of charge. The there is the cigarette lighter socket voltmeter I looked at on a lady's boat at Rickmansworth, it was hunting up and down by a similar amount - toys for boy racers, nothing more and nothing less.

 

The boat is going to be sold soon but I am sorry I did not shell out for a BVM type gauge from a reputable supplier when I bought the boat.

[ronnietucker]

You could try one of these gadgets:

http://smile.amazon.co.uk/gp/product/B00157KANE

 

You hook it to the battery, hold the button down for a few seconds, the element inside heats up, and it'll tell you whether the battery is in good condition or not.

[Boater Sam]

1 minute ago, ronnietucker said:

You could try one of these gadgets:

http://smile.amazon.co.uk/gp/product/B00157KANE

 

You hook it to the battery, hold the button down for a few seconds, the element inside heats up, and it'll tell you whether the battery is in good condition or not.

Not a lot of use I found.

[Tony Brooks]

5 minutes ago, ronnietucker said:

You could try one of these gadgets:

http://smile.amazon.co.uk/gp/product/B00157KANE

 

You hook it to the battery, hold the button down for a few seconds, the element inside heats up, and it'll tell you whether the battery is in good condition or not.

 

Please no, by all means you use it but do not advise others to do the same.

 

They are just a cheap high rate discharge tester than can be manipulated to show almost anything depending upon the batteries state of charge. They also need their loading matching to the CCA (start battery) under test. If the battery is smaller or larger the result will be invalid.

 

In the days of many failures of car starts in frosty weather those instruments were an easy way for the unscrupulous to sell  a new battery to a customer because the meter showed "dead" and then recharge the discharged battery to pass or sell on.

 

For an ordinary boater monitoring voltage and charging current a few times a day throughout the time on the boat will give a far quicker indication of incipient faults developing.

 

 

[Bee]

They do have their uses and I have been charging my engine start battery at home all winter, every few weeks bung it on charge and its been behaving like a good battery, apparently taking and holding a charge. In fact the thing is totally, completely dead. That little device would have told me that a high rate of discharge would have lasted a couple of seconds at most. Stupid battery. Stupid battery charger. Maybe stupid owner too.

[Tony Brooks]

14 minutes ago, Bee said:

They do have their uses and I have been charging my engine start battery at home all winter, every few weeks bung it on charge and its been behaving like a good battery, apparently taking and holding a charge. In fact the thing is totally, completely dead. That little device would have told me that a high rate of discharge would have lasted a couple of seconds at most. Stupid battery. Stupid battery charger. Maybe stupid owner too.

Only if it is matched to the CCA/Ah of the battery under test. Using one for a car battery of maybe roughly 30Ah on a faulty/sulphated 110Ah battery may very well show no fault, especially when it has just come off charge. It sounds like your battery is totally sulphated s it charges fast and then discharges fast. Comparing a hydrometer test and rested voltage test would give that information without needing to match the equipment to the battery. Actually putting a voltmeter across it and operating the starter/heavy load on an inverter would also tell you that.

[WotEver]

2 hours ago, ronnietucker said:

You could try one of these gadgets:

http://smile.amazon.co.uk/gp/product/B00157KANE

It’s not even heavy enough to make it a decent doorstop. 

[peterboat]

4 hours ago, Tony Brooks said:

Only if it is matched to the CCA/Ah of the battery under test. Using one for a car battery of maybe roughly 30Ah on a faulty/sulphated 110Ah battery may very well show no fault, especially when it has just come off charge. It sounds like your battery is totally sulphated s it charges fast and then discharges fast. Comparing a hydrometer test and rested voltage test would give that information without needing to match the equipment to the battery. Actually putting a voltmeter across it and operating the starter/heavy load on an inverter would also tell you that.

They normally do have CCA bands on them to help out, and they should be used on a fully charged battery