Reply
 
Thread Tools Search this Thread Display Modes
 
Old 11-04-2018, 12:40 PM   #1
Guru
 
JDCAVE's Avatar
 
City: Lions Bay, BC
Country: Canada
Vessel Name: Phoenix Hunter
Vessel Model: Kadey Krogen 42 (1985)
Join Date: Apr 2011
Posts: 1,933
Battery load tester

Is a cheap analog load tester sufficient for once or twice a year tests or should I consider a digital model? Also, are 6v FLA GCís with their high amp hour rating a special case? There are some models that indicate they can test 6 and 12 volts, but others just indicate they are for 12v batteries and do not specify otherwise.

Suggestions?

Jim
__________________
Advertisement

JDCAVE is offline   Reply With Quote
Old 11-04-2018, 12:48 PM   #2
Enigma
 
RT Firefly's Avatar
 
City: Slicker?
Country: Bumpkin?
Join Date: Oct 2007
Posts: 11,323
Greetings,
Mr. JD. I may not know any better but I use one like this:
https://www.harborfreight.com/100-am...ter-61747.html


__________________

__________________
RTF
RT Firefly is online now   Reply With Quote
Old 11-04-2018, 12:48 PM   #3
Guru
 
psneeld's Avatar
 
City: Avalon, NJ
Country: USA
Vessel Name: Freedom
Vessel Model: Albin 40
Join Date: Oct 2011
Posts: 18,007
Unless you find some miracle digital one, I have had better results with the analog ones as they are simplistic.

None has ever lied, but 2 digital ones, including an expensive one at a place of work did.
psneeld is online now   Reply With Quote
Old 11-04-2018, 01:36 PM   #4
Guru
 
dhays's Avatar
 
City: Gig Harbor
Country: United States
Vessel Name: Kinship
Vessel Model: North Pacific 43
Join Date: May 2015
Posts: 7,159
What are you actually trying to test? It was my understanding that a typical load tester will test a batteries ability to produce cold cranking amps. That would be good for a start battery but how useful is that for testing deep cycle batteries such as used for a house bank?
__________________
Regards,

Dave
SPOT page
dhays is offline   Reply With Quote
Old 11-04-2018, 01:40 PM   #5
Guru
 
psneeld's Avatar
 
City: Avalon, NJ
Country: USA
Vessel Name: Freedom
Vessel Model: Albin 40
Join Date: Oct 2011
Posts: 18,007
Quote:
Originally Posted by dhays View Post
What are you actually trying to test? It was my understanding that a typical load tester will test a batteries ability to produce cold cranking amps. That would be good for a start battery but how useful is that for testing deep cycle batteries such as used for a house bank?
The digital ones may let you check 20 amp hr draw....

But even the stone age ones let you know if your battery has any guts left in it...just no accurate number to associate with deep cycle numbers.

But voltage tells you even less, much less....
psneeld is online now   Reply With Quote
Old 11-04-2018, 03:17 PM   #6
Guru
 
JDCAVE's Avatar
 
City: Lions Bay, BC
Country: Canada
Vessel Name: Phoenix Hunter
Vessel Model: Kadey Krogen 42 (1985)
Join Date: Apr 2011
Posts: 1,933
Quote:
Originally Posted by john61ct View Post
If you are trying to judge the State of Health of a deep cycling House bank, all these are close to useless.

Short of big lab-grade gear costing thousands,

only a 20-hour load test will be accurate for that purpose.

A truncated version, **if** executed exactly the same every time, would be pretty close, providing you executed a benchmark run in the early days after properly commission-charging and breaking in the bank,

if well-coddled, say within the first 50 deep cycles.
Which is why I asked that question.

Jim
JDCAVE is offline   Reply With Quote
Old 11-04-2018, 03:39 PM   #7
Senior Member
 
jungpeter's Avatar
 
City: Everett
Country: US
Vessel Name: SPIRIT BEAR
Vessel Model: PACIFIC TRAWLER 40
Join Date: Mar 2013
Posts: 166
Hi JDCAVE,

Unfortunately, there's no easy way to measure battery "health" accurately for deep-cycle house batteries, unless you wish to resort to laboratory-grade test equipment, and rigorous test procedures, executed immediately after purchase, and executed routinely thereafter. Digital/analog handheld el-chepo battery conductance testers (ESPECIALLY Harbor Freight versions, for instance) are simply a waste of money and time, and I have to agree with john61ct. For reference, you may want to read:

https://marinehowto.com/are-battery-...ters-worth-it/

Regards,

Pete
jungpeter is offline   Reply With Quote
Old 11-04-2018, 04:41 PM   #8
Guru
 
tiltrider1's Avatar
 
City: Seattle
Country: USA
Vessel Name: AZZURRA
Vessel Model: Ocean Alexander 54
Join Date: Aug 2017
Posts: 811
If you are trying to test your start battery, the battery must be full charged first for the resistance style battery testers to work correctly. The new digital ones don’t require a fully charged battery to do their test. The digital battery testers will give you much more data but most just want to know if the battery is good or not and could careless about how good or bad the battery is. Be careful, there are some resistance style testers with digital displays.
tiltrider1 is offline   Reply With Quote
Old 11-04-2018, 04:48 PM   #9
Guru
 
caltexflanc's Avatar
 
City: North Carolina for now
Country: USA
Vessel Name: Small Incentive
Vessel Model: Boston Whaler 130 Sport
Join Date: Aug 2011
Posts: 4,621
For deep cycle batteries, I far prefer a good battery monitor system. For start batteries a decent load tester works fine.
__________________
George

"There's the Right Way, the Wrong Way, and what some guy says he's gotten away with"
caltexflanc is offline   Reply With Quote
Old 11-04-2018, 06:58 PM   #10
DDW
Senior Member
 
City: San Francisco
Country: USA
Join Date: Apr 2018
Posts: 410
But any good AH counter can be used to *determine* the capacity of the battery. The only thing the %SOC number is used for is to display a number for the amusement of the user. All you need to do is observe the voltage at particular points of AH usage, and the capacity will reveal itself. For example, if your 200 AH (advertised) bank drops to 11.5V after 100 AH have been drawn from it, you've got closer to a 100 AH bank now.

This is not true of the resistance type testers discussed above. In fact they reveal very little that can't be seen with a cheap voltmeter and a heavy load.

Western Mountain Radio makes some very nice testers, but for a 400 AH battery bank you really need the 500W version and that's around $1K. If you can break your bank into 200 AH pieces, the $160 one will do it one at a time.
DDW is online now   Reply With Quote
Old 11-04-2018, 09:17 PM   #11
Guru
 
BruceK's Avatar
 
Join Date: Oct 2011
Posts: 8,811
Quote:
Originally Posted by RT Firefly View Post
Greetings,
Mr. JD. I may not know any better but I use one like this:
https://www.harborfreight.com/100-am...ter-61747.html


I bought one of those. The load test is complete when you smell smoke. Despite the criticism, I think it achieves purpose.
__________________
BruceK
Island Gypsy 36 Europa "Doriana"
Sydney Australia
BruceK is offline   Reply With Quote
Old 11-05-2018, 06:51 AM   #12
Guru
 
psneeld's Avatar
 
City: Avalon, NJ
Country: USA
Vessel Name: Freedom
Vessel Model: Albin 40
Join Date: Oct 2011
Posts: 18,007
Quote:
Originally Posted by BruceK View Post
I bought one of those. The load test is complete when you smell smoke. Despite the criticism, I think it achieves purpose.
I agree with the backyard mech evaluation/perspective...just have to have an eye and an ear for that sort of thing. Accuracy? Heck no but does tell you something.

Plus one may have one around FOR starting batteries, etc.

As has been posted, without an involved test, you don't know exactly, so rule of thumb tests that are easy work for me.
psneeld is online now   Reply With Quote
Old 11-05-2018, 07:23 AM   #13
FF
Guru
 
FF's Avatar
 
Join Date: Oct 2007
Posts: 17,931
The golf course folks have an expensive unit that can give a snapshot , charged or discharged , but there pri$y.

Just as you would not use a single oil sample to judge an engine , installing a SOC meter can keep track over time of the battery sets condition.

A long history is better than a snap shot.


On buying a boat , just plan on replacement in time.
FF is offline   Reply With Quote
Old 11-05-2018, 10:02 AM   #14
Guru
 
City: Anacortes
Country: USA
Join Date: Nov 2012
Posts: 523
Iím not sure what the digital ones that form an opinion in a moment are doing. The hf auto shop ones are simply applying a load and watching a volt meter to see if the voltage drops under load. Actually they are pretty effective for a bad battery, good/bad outcome. But donít do squat for measuring the amp hour capacity.

I used to test amp hour loads for a 12 volt 18 amp hour battery set when we absolutely had to know if it was going to last for its intended use. I had a set of large resistors of known value that I would bolt or clamp to my metal bench. Then connect them to the battery. The resistance would pull around 20 amps if I recall. Iíd let the. Go until they hit a specified voltage. You could chart the voltage every 10 minutes or so. Interesting part was the characteristics of the ďbadĒ ones. Some would have the same curve as when new, just a little lower. Others would go along looking just a little lower than normal and then fall off really quickly. Iím leery of any device that samples just a few minutes to form its conclusion.

Oh, and those huge resistors would get hot enough to heat my shop. To do my current 1200 amp-hour house bank would take considerable time and for most, the heat would be dangerous enough to require some thought.

To test amp hour capacity at this scale, typically canít practically be done in place. Itís possible, but very few would pull it off safely. Plus if you did not test and plot when new, you have little to compare to.

My soc meters get reset occasionally, call me skeptical. Maybe if they took the voltage at repeated soc points, but they are all different. Sometimes the batt has been fully charged, other times not. Sometimes there are background loads. Too many variables. Helpful, but Iím skeptical this accurately approximates a real amp hour test.
ghost is offline   Reply With Quote
Old 11-05-2018, 05:16 PM   #15
Guru
 
City: Anacortes
Country: USA
Join Date: Nov 2012
Posts: 523
Pragmatic me would not vary the load. Only reason to do that is if you are the mfg and trying to publish a statistic. The value to an individual would be better served to establish their own baseline with a load that is consistent each test, thus a fixed resistive load answers perfectly. The value is then plotting at a future date and establishing how much capacity has been lost would be the goal. Keeping the test consistent would be the hardest part.
ghost is offline   Reply With Quote
Old 11-05-2018, 05:34 PM   #16
Senior Member
 
Roamer Blue's Avatar
 
City: Toronto ON
Country: Canada
Join Date: Aug 2016
Posts: 111
Quick learning curve with these, use it a bit, on new and old batteries, you'll have a good idea whether there's some "oomph" left, or if it is getting tired. Your car, the neighbor's car, the kid's car, passers by, down by the grocery store on "cheque day" for some rougher examples... One battery at a time please... see what will hold the needle high, and what will get it to degrade over the 10 seconds of test time...And then extrapolate your learning for the deep cycle power houses...


Type A personality, OCD, engineers may now blow their brains out at this completely seat of the pants foolishness that lacks any scientific content whatsoever... but I've still only spent what? $24 on Amazon? and test each battery in 10 seconds...





Quote:
Originally Posted by RT Firefly View Post
Greetings,
Mr. JD. I may not know any better but I use one like this:
https://www.harborfreight.com/100-am...ter-61747.html


Roamer Blue is offline   Reply With Quote
Old 11-05-2018, 05:44 PM   #17
Guru
 
psneeld's Avatar
 
City: Avalon, NJ
Country: USA
Vessel Name: Freedom
Vessel Model: Albin 40
Join Date: Oct 2011
Posts: 18,007
Exactly....
psneeld is online now   Reply With Quote
Old 11-05-2018, 07:00 PM   #18
Senior Member
 
alfamike's Avatar
 
City: Camarillo
Country: USA
Join Date: May 2015
Posts: 261
Battery Testers

I use the newest Midtronics tester.

it does test for reserve capacity.

Alfa Mike
alfamike is offline   Reply With Quote
Old 11-05-2018, 07:41 PM   #19
Enigma
 
RT Firefly's Avatar
 
City: Slicker?
Country: Bumpkin?
Join Date: Oct 2007
Posts: 11,323
Greetings,
Mr. RB. Thanks for that. I was feeling pretty dumb for posting MY test equipment but all I really want is to see, as you put it, the "oomph". Will continue in lieu of UL labs....
__________________
RTF
RT Firefly is online now   Reply With Quote
Old 11-05-2018, 07:59 PM   #20
Guru
 
BruceK's Avatar
 
Join Date: Oct 2011
Posts: 8,811
Quote:
Originally Posted by RT Firefly View Post
Greetings,
Mr. RB. Thanks for that. I was feeling pretty dumb for posting MY test equipment but all I really want is to see, as you put it, the "oomph". Will continue in lieu of UL labs....
Well don`t, several of us own that basic device and it does tell us something that is adequate for many purposes. If you have LAs nothing really takes the place of a hydrometer for testing for battery condition, and hydrometers cost only 3/8 of 5/8 of not very much.
__________________

__________________
BruceK
Island Gypsy 36 Europa "Doriana"
Sydney Australia
BruceK is offline   Reply With Quote
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off





All times are GMT -5. The time now is 12:52 PM.


Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2018, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2006 - 2012