12 volt battery tester?

[Rebotco]

Does anyone have any experience of these types of battery tester?

They claim to give the SOC and remaining capacity etc, but are they reliable or accurate?Battery analyser

[dor]

Looks like the kind of thing battery sellers use to try and convince you the battery they’ve had on the shelf for two years is in excellent condition.

[Tony Brooks]

As usual on such sites not enough info to form an informed oppinon.

 

It looks like a glorified high rate discharge tester and as there is no direct conversion between CCA and Ah mainly designed for start batteries and even then with a typical 100Ah inland start battery it is likely to pass our huge, in comparison to a car, batteries as serviceable when they have problems.

 

HRD testes need matching to the battery capacity. I doubt this one is any good for much over 50 ah

[Richard10002]

59 minutes ago, Rebotco said:

Does anyone have any experience of these types of battery tester?

They claim to give the SOC and remaining capacity etc, but are they reliable or accurate?Battery analyser

Snake Oil!

[Sea Dog]

I connect my batteries to loads closely representative of my boating lifestyle. You know, Fridge, water pump, lighting, etc on the 12v distribution and 230v stuff via my inverter. I then do a long test, monitoring their charge and discharge until I see them charging a lot quicker than they used to and holding charge for a shorter time than I am happy with under those realistic load conditions. When that happens (7 years last time) I take them out and evaluate another set in a similar way. There are battery testers which work differently, but this method works for me.

 

[Rebotco]

1 hour ago, Tony Brooks said:

As usual on such sites not enough info to form an informed oppinon.

 

It looks like a glorified high rate discharge tester and as there is no direct conversion between CCA and Ah mainly designed for start batteries and even then with a typical 100Ah inland start battery it is likely to pass our huge, in comparison to a car, batteries as serviceable when they have problems.

 

HRD testes need matching to the battery capacity. I doubt this one is any good for much over 50 ah

Yes I appreciate what you say.

They are surely aimed at the car starter battery market.

But even so, if used for individual batteries on a boat, would they not give a good indication?

They do require you to enter the rated CCA before they will operate.

[Richard10002]

35 minutes ago, Rebotco said:

Yes I appreciate what you say.

They are surely aimed at the car starter battery market.

But even so, if used for individual batteries on a boat, would they not give a good indication?

They do require you to enter the rated CCA before they will operate.

No! ?

[Tony Brooks]

16 minutes ago, Rebotco said:

Yes I appreciate what you say.

They are surely aimed at the car starter battery market.

But even so, if used for individual batteries on a boat, would they not give a good indication?

They do require you to enter the rated CCA before they will operate.

To the best of my knowledge all testers based on HRD testing need to be matched to battery capacity. I thin this one does it by altering the discharge time acording to the battery's CCA.

 

Its basically an electric fire so it puts a known but high load on a battery for a specific time. I think the linked one does the timing on its own based on the CCA you enter. the basic HRD then shows the voltage over that period and from memory the minimum voltage shown must be 10V or above. If the battery can't maintain that voltage it shows as faulty. Obviously this meter processes the information and probably has  a guess at other parameters. Again probably based on the voltage level and speed of fall against the CCA you entered.

 

If my guess that its designed for a 50Ah equivalent battery and you put a100Ah battery on it that battery will maintain its voltage for twice as long as a 50 Ah one. Likewise if your 100 Ah battery is 50% sulphated it could still show as good on that tester where as in general the rule of thumb is that when a battery has lost 50% of its capacity it should be considered as requiring replacement. Its even possible that a minor short between plates in a 100Ah battery could be hidden by the extra capacity

 

This is before you think about how genuine deep cycle batteries with thick plates will stand up to the high currents involved in HRD testing.

 

You would do far better to put the money towards a decent ammeter and voltmeter/battery monitor so you can note is reading at various times over the day and get to know what is normal for your bat and use. then when its abnormal either explain it or find out why.

 

Fast charge and fast discharge = loss of capacity (sulphated).

Slow charge and fast discharge = shorting cell (if no abnormal external load).

Bulging case ends indicates excess sulphation.

Hot areas on charging batteries, gassing individual cells, dry individual cells = internal shorts

 

Specific gravity indication of charge being less than that implied by rested voltage = sulpahtion.

[Rebotco]

4 minutes ago, Richard10002 said:

No! ?

Is that opinion based on experience or prejudice??

[Tony Brooks]

Another thing, even assuming the thing is matched to the battery's CCA a serviceable but discharged battery is likely to show up as faulty. this is because it won't be able to maintain the voltage for the required time.

[ditchcrawler]

41 minutes ago, Richard10002 said:

No! ?

Select Standard, set Battery Rating

[blackrose]

Looks like crapola to me. Why don't you get yourself a proper battery monitor? 

[Dr Bob]

1 hour ago, Rebotco said:

Is that opinion based on experience or prejudice??

When we got our new boat, it was delivered with a set of LA's that were on their last legs. We suspect at the factory they left the power to the boat on for a week or so with the fridge running etc after turning off the shore power. I measured the capacity by discharging at a known load and checking rested voltage - then checking individual battery voltages by monitoring voltage drop in a short time frame with a 20A discharge. The data showed all 4 batteries were 'crap' and about 50% of original capacity.

The manufacturers sent someone out with an HRD meter - thinking it was likely one battery at fault as 4 would never fail in the same way -which showed all 4 were similar and were borderline charged. Not really very useful to indicate the status. They were replaced!

The meter you posted will be a load of cr&p in telling you the state of your batteries. Buy a decent battery monitor. You cant go wrong with a BMV or a Nasa. The BMV will be ideal when you get the stage where you know about boat 12v batteries and decide to get Lithiums.

[Tony Brooks]

Agree a decent battery monitor and regular monitoring together with a little knowledge is the best way for ordinary boaters to diagnose battery faults a song as they ignore any % charged and associated readings.

 

I suspect the HRD tester the factory used was not matched to the battery capacity (it was too "small").

[Murflynn]

a cheap version of what the AA man uses before he tells you you need a new car battery.

 

 

I regularly test my leisure (actually traction in my case - leccy boat) batteries by the good old-fashioned headlamp bulb discharge test, applied to each battery in turn after disconnecting from each other.  Just make sure the bulb is not close to anything flammable - it gets damn hot.

[Richard10002]

14 hours ago, Rebotco said:

Is that opinion based on experience or prejudice??

Part experience, part judgement, part logic  

[Rebotco]

OK, it seems this is universally rubbished on here.

So I'm looking at "proper" battery monitors.

I'm down to a choice of the Victron BMV 700 or the NASA BM1.

I don't have (or want) a smart phone, so the bluetooth versions are of little interest.

The NASA one seems about £30 cheaper than the Victron, doing much the same job.

Any comparisons I should watch out for? Is one better than the other?

[Glynn]

Ive had both the NASA BM2 and now the Victron BMV712. I prefer the Victron, however the NASA has a good large display so is easy to read.

But the Victron has bluetooth to your phone so thats better I think.

[Tony Brooks]

21 minutes ago, Rebotco said:

OK, it seems this is universally rubbished on here.

So I'm looking at "proper" battery monitors.

I'm down to a choice of the Victron BMV 700 or the NASA BM1.

I don't have (or want) a smart phone, so the bluetooth versions are of little interest.

The NASA one seems about £30 cheaper than the Victron, doing much the same job.

Any comparisons I should watch out for? Is one better than the other?

 

I am sure either will do the job providing you follow certain procedures.

 

1. Unless you completely understand the instructions, reprogram the instrument and then  ensure it is very regularly synchronised on to account use the percentage charged readout or anything that purports to tell you how much time or charge is left in the batteries.

 

2. Learn how to infer state of charge from rested voltage (and what rested voltage means).

 

3. Fully charge at least once a week by reference to tail current (and what tail current means).

 

4. Try to stick to the 50% discharge "rule" as much as possible. 50% discharged = around 12.2 to 12.3 rested voltage.

 

 

[Sea Dog]

1 hour ago, Rebotco said:

Any comparisons I should watch out for? Is one better than the other?

I plumbed for the Victron because it has a 500amp shunt. The NASA was either 100 or 200, so insufficient for the maximum current draw of my inverter.

[Col_T]

I went for the BM1 - nice, large, easy to read display - which is currently placed so I can see it whilst cruising, to keep an eye on amps and voltage being generated into the batteries. It has a 100A shunt (the BM2 has a 200A), which is fine for our use - we don't have energy hungry 240v appliances on board. I know that it has SoC and hours of charge remaining displays, I just don't bother ever looking at them as they are so likely to be wrong.

[ditchcrawler]

My Stirling performed well for about 14 years before it let its smoke out, nut and bolt came lose on the heat sink of the voltage regulator

[Dr Bob]

2 hours ago, Rebotco said:

The NASA one seems about £30 cheaper than the Victron, doing much the same job.

Any comparisons I should watch out for? Is one better than the other?

Whilst you may not be interested in bluetooth now, in the future you may be.

Also if you become more interested in 12V stuff, and you start thinking about Lithiums or more advanced monitoring of power, the Victron monitor allows you to integrate with other bits of kit. I have mine connected to a Rasp pi so I can collect data on the Victron connect site. The attached chart is the sort of output you can get. Once again you may not be interested in that now....but you may be in future. Accessing boat power data remotely is an advantage.

I prefer the low profile of the BMV display.

 

 

[Tony Brooks]

I find that interesting. Especially a sit must show how your BMS shuts the charging down, and how    quickly the lithiums got to what is considered a safe full charge. Lead acids would only be about 80% charged in that time.

 

Would it be an electric coffee maker at about 09.15 and again at about 10.15? If not what was it?

 

Thanks

[mrsmelly]

I've had several and prefer the nasa bm2. Main reason is that for grown ups no glasses needed to read it and waterproof so can be mounted outside.