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Topic: Speaking Of Harbor Freight...
Posted By: MEXICOWANDERER on 11/03/18 01:54pm

[image]

This load tester costs fifty dollars. I own one. It will CORRECTLY load test a tiny garden tractor battery all the way up to a 160 lb 8-D battery.

CORRECTLY

The cheese grater type testers auto parts stores use are a joke. Like a heart stress test done in a Chaise Lounge.

"It tested good. Why did it die?"

Immortal words of victims who were deceived into believing cheese grater 80 or 100 amp fixed load testers are worth the time and trouble. Like comparing a $4.95 socket set to the real thing.

"Look! The voltage went to above twelve. Your alternator is fine!"

With the adjustable load tester you can also load your battery down to 13 volts and check the LOAD TEST validity of an alternator.

Load test between battery negative and the chassis. See smoke?

A carbon pile test is FAR MORE ACCURATE and reliable than a battery impedance test.

Check your campground neighbor's batteries. Get invited over for drinks and dinner. Just joking.

Posted By: theoldwizard1 on 11/03/18 02:19pm

MEXICOWANDERER wrote:


A carbon pile test is FAR MORE ACCURATE and reliable than a battery impedance test.

The old Sun VAT 26, 28, 32 and 40 tester had a big ol' carbon pile in them. Because of the way the test cables were you could put a load on the running engine charging system an see if it was still putting out adequate voltage. The only way to truly do a diode test.

Posted By: MrWizard on 11/03/18 02:32pm

i have one, and it sees use
last use was testing the 200ampHr 154# 8A4D battery, i bought (2)? months ago

as the saying goes "don't leave home with out it"

I can explain it to you.
But I Can Not understand it for you !
....

Connected using T-Mobile Home internet and Visible Phone service
1997 F53 Bounder 36s


Posted By: MEXICOWANDERER on 11/03/18 03:17pm

Thirty years ago the Sun VAT tester cost in excess of six hundred dollars. In 1982 My Autometer 800 amp carbon pile was 300+ dollars. Fifty dollars -- twelve gallons of California people's gasoline. Gambling Hall aficionados who insist at eating at the casino chow hall buffet after waiting in line for an hour, will consider this carbon pile load tester a waste of money.

Posted By: pnichols on 11/03/18 03:40pm

David .... in that photo the unit looks "too small" to contain the loads inside it that can dissipate the heat from the high currents that should result from serioulsy load testing RV batteries.

Shouldn't the high current loads be left on a battery-under-test long enough such that whatever is dissipating the current in the test bed would heat up?

[emoticon]

2005 E450 Itasca 24V Class C

Posted By: MEXICOWANDERER on 11/03/18 05:02pm

That is a home unit and it must be allowed to cool.

I have tested three or four group 31's then let it rest.

  • Find out or best guess a battery's CCA. Golf car batteries use different numbers and time
  • Regular batteries use 50% of CCA rating
  • 500 CCA battery test at 250 amps. Charge battery and twist dial to get 250 amps
  • Watch voltmeter
  • Maintain 250 amp load by twisting dial for more load
  • Keep it at 250 amps for FIFTEEN SECONDS
  • If the voltage sags to below NINE POINT SIX VOLTS the battery is defective
  • Most bad batteries voltages collapse under a very modest load.
Posted By: pnichols on 11/03/18 07:12pm

MEXICOWANDERER wrote:

That is a home unit and it must be allowed to cool.

I have tested three or four group 31's then let it rest.

  • Find out or best guess a battery's CCA. Golf car batteries use different numbers and time
  • Regular batteries use 50% of CCA rating
  • 500 CCA battery test at 250 amps. Charge battery and twist dial to get 250 amps
  • Watch voltmeter
  • Maintain 250 amp load by twisting dial for more load
  • Keep it at 250 amps for FIFTEEN SECONDS
  • If the voltage sags to below NINE POINT SIX VOLTS the battery is defective
  • Most bad batteries voltages collapse under a very modest load.


Thanks for the details on that unit.

Those load application times are so short that probably there's not a lot of heat to deal with if the user lets it cool long enough between those short load application times.

Posted By: joshuajim on 11/04/18 07:25am

MEXICOWANDERER wrote:

[image]

Like a heart stress test done in a Chaise Lounge.


The last heart stress test I had was done lying down (like in a chaise lounge). It was a chemical stress test. They inject a chemical into your blood stream and suddenly you feel like your running a marathon up a mountain. It goes away in a couple of minutes.

Better living through chemistry [emoticon]

RVing since 1995.

Posted By: folivier on 11/04/18 07:55am

What would be the best procedure with this tester for house batteries? Especially 8D sizes?
Thanks!

Posted By: 3 tons on 11/04/18 08:23am

Will this device provide an accurate test on a deep cycle GC battery?

Posted By: MEXICOWANDERER on 11/04/18 10:14am

8-D batteries can have as little as 800 CCA or as much as 1,400 CCA. This tester has to be cranked up to maximum 500 amperes to test the 29 plate premium 8-D battery but it's enough to test the battery.

Make SURE the battery is "over charged" before testing then let it sit for a few hours before testing.

A battery that ALMOST passes may be merely sulfated. These batteries will sag voltage a little below 9.6 volts at the end of the test but stay steady. This is where the HYDROMETER comes into play. Usually giving an 8-D a vigorous overcharge with a manual charger (see equalization) will improve the results of the CCA test allowing the battery to pass muster.

Most bad batteries just fall on their butt when the CORRECT amperage is used for the test. Applying 100-amp "Cheese Grater" tester amperage to a larger than 200 CCA rated battery is a ridiculous "Tickle Me Elmo" exercise in futility.

[image]

This is a "load tester" good for tiny garden tractor batteries. It is utterly useless for anything else. Stores that use this tester do so because it requires no thinking for pimple faced employees who have to unzip their pants in order to count past "10". Ridiculous.

Posted By: MEXICOWANDERER on 11/04/18 10:22am

It cannot reliably test a single three cell battery. Connect two batteries in series. If the series battery shows bad, use a voltmeter on each battery and determine which one is the sick-puppy by doing test # 2 then test # 3

I use TWO HUNDRED AMPS draw for THIRTY SECONDS on a series pair of GC220 golf car batteries.

Posted By: MEXICOWANDERER on 11/04/18 11:22am

The last heart stress test I had was done lying down (like in a chaise lounge). It was a chemical stress test. They inject a chemical into your blood stream and suddenly you feel like your running a marathon up a mountain. It goes away in a couple of minutes.

Hah! Got me! [emoticon]

Yeah the chemical stress test is a real hum-dinger. I felt like I had the flu after the junk was injected. But after the test they injected a second time. An antidote. I guess 17 cups of coffee would do the same thing. The @#$%^&! had me seated in a hospital grade chair -- one padded with 1/4" rags beneath the Naugahyde. The real antidote was learning my heart was healthy. I underwent the radio neuclide test. Supposedly the chemical stress test is far more accurate than the treadmill.

Like testing correctly with batteries and charging. It may be a pain but it's worth every cent.

Posted By: wa8yxm on 11/04/18 03:44pm

I have that dual meter carbon pile. though IT WILL test an 8D or 4D or pair of GC-2.. those are actually a touch beyond what mine can do... THough rated 500 amps (And wear gloves if you are goign that hight) It only hits about 450

YOu need 660 to properly test the batteries listed.

BUT.. Still. Crank it up to the max and if 15 seconds later (When it beeps) You are NOT in the green... That's when I pulled up in front of aq DEKA store and they helped me lift new ones onto the tray.

Home was where I park it. but alas the.
2005 Damon Intruder 377 Alas declared a total loss
after a semi "nicked" it. Still have the radios
Kenwood TS-2000, ICOM ID-5100, ID-51A+2, ID-880 REF030C most times


Posted By: maillemaker on 11/05/18 07:27am

Sounds like a pile of...carbon to me. [emoticon]

When they first built the first nuclear reactor they called it an atomic pile. One of the physicists was impressed, thinking "pile" was "volt" in some language or other (I can't remember the details anymore). Instead it was called a "pile" because it was constructed out of a pile of carbon bricks. [emoticon]

Steve

1990 Winnebago Warrior. "She may not look like much but she's got it where it counts!"
Posted By: MEXICOWANDERER on 11/05/18 07:46am

I devised the GC 220 formula because of the higher capacity lower amperage of the DUT. Nice to have had pallets of new T105 batteries, Ramcar 3 cells, and various good, fair, and failed batteries.

The extra 15 seconds does build up heat but the watt seconds = a battery tested at 400 amps drawn for the standard 15 seconds.

Slap an intake fan on this gizmo and there you go.

Posted By: MEXICOWANDERER on 11/05/18 07:54am

Chop a hole in the case and fit

a 3 VOLT full scale AC voltmeter and there's your SUN VAT 28-40 STATOR/DIODE tester. Alternating Current VOLTmeter

Connect your inductive DC ammeter to the large alternator wire, twist the handle and read alternator amperes charging capacity.

Mother Fletcher's Do It Myself VAT tester.

Posted By: CA Traveler on 11/22/18 09:36am

MEXICOWANDERER wrote:

I use TWO HUNDRED AMPS draw for THIRTY SECONDS on a series pair of GC220 golf car batteries.
I have a different brand 500A tester and they recommend a 15 minute wait between 15 second tests.

Question. Does a 250A 15 second test then 15 minute wait then a second 250A 15 second test accomplish the same thing as a 30 second test?

2009 Holiday Rambler 42' Scepter with ISL 400 Cummins
750 Watts Solar Morningstar MPPT 60 Controller
2014 Grand Cherokee Overland

Bob


Posted By: ktmrfs on 11/22/18 09:52am

3 tons wrote:

Will this device provide an accurate test on a deep cycle GC battery?


yup if you connect two in series. I have one and have tested a GC2 pair and if you do as Mex says it works fine.

2011 Keystone Outback 295RE
2004 14' bikehauler with full living quarters
2015.5 Denali 4x4 CC/SB Duramax/Allison
2004.5 Silverado 4x4 CC/SB Duramax/Allison passed on to our Son!


Posted By: MEXICOWANDERER on 11/22/18 10:34am

CA Traveler
That would be better than nothing. Pay attention to the volt scale when load is turned off. If the return to 12 volts is a -lot- more sluggish after the 2nd load test then that is not a good sign.

Have the batteries connected in series and after the test if the series cable is hot, the test is void. The cable must not heat up.

Posted By: CA Traveler on 11/22/18 12:40pm

Mfg says 1/2 of CCA, 15 seconds and use this chart.

[image]
[image]Click For Full-Size Image.

Posted By: MEXICOWANDERER on 11/22/18 01:13pm

...and for automotive style batteries you should follow the chart...

What is the CCA of a GC220 battery?
Not advertised. Irrelevant format.

I developed the GC220 test protocol. It took about a week to profile the values. That was in the 1980's

It's accuracy is very close to that of the BCI test.

It is based on 200x2 amperes hours, and compensation for lots of less reactive plate area.

L16's require an 800 ampere adjustable load carbon pile tester and different 3-step test.

Professionals use Auto Meter carbon pile load testers

Auto Meter Products 800A Carbon Pile Load Tester - SB-5/2
Brand New
$560.21
Top Rated Seller
Buy It Now

Posted By: MEXICOWANDERER on 11/22/18 01:23pm

Use a variable carbon pile load tester

In conjunction with a DC inductive ammeter

Place inductive loop around battery wire coming from the alternator.

Increase engine speed to 2,000 RPM

Slowly crank up the load. Observe inductive ammeter amperage it will climb.

At a certain point near 12 volts the inductive ammeter will start showing less and less amps as the carbon pile load keeps increasing

This is because the carbon pile load has reduced alternator voltage so low the rotor (field) current is insufficient to develop maximum excitation of the rotor field strength.

Posted By: CA Traveler on 11/22/18 09:43pm

Mex Oops my bad as a post is missing.

1. I have the 2x GC2 220AH house batteries to test and appreciate your input. The tester manual says 160AH max for deep cycle batteries.

2. I also want to test group 31 950 CCA starting battery. Mfg says to use 1/2 of CCA as the amp setting for the tester and use the chart I posted. Hence 475A and check the voltage after 15 seconds. I'll try that but am doubtful that the el cheapo home type 500A carbon pile tester will really handle that amount of amps.

So learning how to interpret the results and record them so that I have a baseline for the batteries to compare in the future for changes.

Others may have L16 or 8D batteries and need a 800A+ tester but I'd like to have a reasonable expectation of a good test with my batteries and the 500A tester.

Posted By: MEXICOWANDERER on 11/22/18 10:06pm

Open your case and then saw and drill holes to fit a 120 mm 12 volt fan -- don't cheapen out here -- get one that blows some air.

"But there's no room inside!"

Who said anything about inside?

Get a wire screen fan guard.

Don't worry bout control or switches, when you snap the battery clamps off the fan stops. The fan will cool the unit down in a tenth the time.

Do the fan thing and you can test thirty batteries per hour if that's your wish.

Even a 1100 CCA 8-D isn't going to fall on it's ass when 500 amps is sucked out of it. A bit of common sense will reinforce the notion that at the 15 second mark the voltage isn't going down like disconnected elevator.

Bad batteries always dump volts rapidly when amperage draw is maintained. Very common is so see amps slump to 30 and volts at 4 volts and dropping.

Your 500 amp machine will work just fine. The manufacturer knows where he saved money and so he does not want to see it get very hot. Stick a fan on it and be done with it.

Garbage Reman Alternator ID
"Warranty Void If Battery Is Not Recharged Prior To Starting Engine"

Posted By: wa8yxm on 11/23/18 07:58am

CA Traveler wrote:

Mex Oops my bad as a post is missing.

1. I have the 2x GC2 220AH house batteries to test and appreciate your input. The tester manual says 160AH max for deep cycle batteries.

2. I also want to test group 31 950 CCA starting battery. Mfg says to use 1/2 of CCA as the amp setting for the tester and use the chart I posted. Hence 475A and check the voltage after 15 seconds. I'll try that but am doubtful that the el cheapo home type 500A carbon pile tester will really handle that amount of amps. .


My Harbor Freight carbon pile dual meter job hitx 450 amps with good batterie. Never gotten it up to 150.. I test my pair of 220 amp hour GC-2 at 450. THey pass till they don't then the new ones pass again.

Posted By: Cummins12V98 on 11/23/18 08:13am

Harbor Freight, NO THANKS!!!

2015 RAM LongHorn 3500 Dually CrewCab 4X4 CUMMINS/AISIN RearAir 385HP/865TQ 4:10's
37,800# GCVWR "Towing Beast"

"HeavyWeight" B&W RVK3600

2016 MobileSuites 39TKSB3 highly "Elited" In the stable

2007.5 Mobile Suites 36 SB3 29,000# Combined SOLD

Posted By: ktmrfs on 11/23/18 09:57am

Cummins12V98 wrote:

Harbor Freight, NO THANKS!!!


in lots of cases I stay away from Harbor Freight. However in this case the harbor freight load tester is actually a good device and worth more than what they charge for it.

Posted By: CA Traveler on 11/23/18 10:17am

ktmrfs wrote:

in lots of cases I stay away from Harbor Freight. However in this case the harbor freight load tester is actually a good device and worth more than what they charge for it.
Occasionally I'll buy from HF. The 800A load tester Mex referenced is very nice but $500+ is hard to swallow.

Posted By: MrWizard on 11/23/18 10:30am

I have one I used it to test surplus batteries before buying
And I use it to test batters after installed
I used it to test the (5)*135ampHr = 675 ampHrs AGM bank I installed in the Safari
And the 200 ampHr 4d AGM, I put here in the Bounder

I've been very happy with it, good value
Your GC are not a problem

Posted By: T18skyguy on 11/23/18 10:31am

ktmrfs wrote:

Cummins12V98 wrote:

Harbor Freight, NO THANKS!!!


in lots of cases I stay away from Harbor Freight. However in this case the harbor freight load tester is actually a good device and worth more than what they charge for it.


A lot of Harbor freight stuff is fine for the job, but if its a mission critical job, I buy quality. I once bought a Harbor Freight air conditioning manifold gauge set. I had it hooked up to the AC connectors correctly, and it blew up in my face. Lesson learned.

Retired Anesthetist. LTP. Pilot with mechanic/inspection ratings. Between rigs right now.. Wife and daughter. Four cats which we must obey.

Posted By: MEXICOWANDERER on 11/23/18 12:08pm

Building a very high quality adjustable carbon pile load tester is expensive.

High quality means a precise linear load action of the carbon wafer stack.

The only thing the HF unit is weak in is the smoothness of the applied load.


And the lack of a fan.

AMAZON AMAZON AMAZON


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