Foretravel Owners' Forum For owners and Fans of Foretravel Motorcoaches September 10, 2025 ...

Load test setup

September 19, 2019, 08:42:58 pm

Picked up a set of parts to test a set of portable "power generators" we acquired. 

Can put a precision load on a battery. 

20 amps max.  Requires a separate 12 volt plus or minus .5 volt power supply.

250W DC 12V Discharge Battery Capacity Tester Module With DC Electronic Load...

From China through a us distributor

I added an in-line from battery source powerwerks gauge to verify the load banks gauge and the total power consumed.

I would think this would be a accurate way to test any batteries actual capacity.

The powerwerks gauge in line could be used for various tests and monitoring.

Powerwerx Watt Meter, DC Inline Power Analyzer, 45A Continuous, 12 Gauge,...

Quote Selected

Re: Load test setup

Reply #1 – September 20, 2019, 10:54:40 am

That thing doesn't look to safe... looks like it is a fire waiting to happen.. no way I'd use that in my garage let alone my house.. might be a sure way for an insurance claim or worse

Quote Selected

Re: Load test setup

Reply #2 – September 20, 2019, 12:05:01 pm

Scientific branch grade product.  Has a fuse in its circuit board.  Used it  multiple times yesterday to draw down my set of power generators internal li-ion prismatic power cells.  .  The cooling fan visible on the front of the heat sink are separately powered from the board mounted 12 volt 2.5mm input plug.  .7amps for the fan to cool the heatsink.

The powerwerks power useage gauge matches the units indicated amp loading and the voltages very closely.

At a steady 10 amps the heat sink is warm to the touch,  at 20 amps it gets fairly hot.

After I am done with my testing of my 4Patriots power generators I want to put this on my coach batteries individually to verify their actual capacities.  First the house,  second the engine start set of optimas.

Versus using a light bulb? Or some other load.

My power generators were rated at 50 amp hours of 12  volt output and the 10 amp loading showed the generators put out 55 amp hours in 5.5 hours.

We are wiring the coach and house to be able to plug the house into the coaches 83 amp generator if needed.

The power generators can be daisy chained to double the capacity and I have 2 Lion energy 100 watt solar panels that can charge each generator separately or be run in series to charge either or both units at 100/200 watts.

It's an amazing device for the use. One tenth the price of similar equipment my buddy has seen.

With the powerwerks in line gauge on the output side of the solar into the generators I can verify the panels output at the power generators input end to quantify any power loss in the wiring.

If a emergency occurs the systems other pieces can put water pressure to our home from bladders with pumps powered indirectly by the generators.  Or transfer water to the moveable bladders from any source then into the house.

Or fill or run the coach itself off the same systems parts.

The lion solar panel set can be clamped directly to the coaches batteries for additional charging options if needed,

As we live in shaky town and looking around here there is no way to leave so cal after an emergency.  Total grid lock.

We have another town house in Las Vegas that's empty on purpose for our uses.

Just wanted to test everything in the system and the coach prior to any real need and to be able to retest over time to verify these generators output and the coaches batteries for a baseline.

$70 for a bench grade adjustable load bank is inexpensive.  I have 2 of the testers.  Both show exactly the same readouts,

I assume these are test equipment for the Chinese battery makers?

As usual if you think these are unsafe do not buy one.

I ran both of mine at 20 amps for 2 1/2 hours each to test them outdoors.

Versus drive your coach somewhere and  disconnect the battery cabling to test the batteries individually?

This would work well to test your li-ion batteries with a calibrated load and with the powerwerks gauge you can see all the needed info live.

$150 system with the various cables needed to attach the load and gauge and hook up them to any battery.

Plus it's pfun. 

Automotive carbon pile load banks are ineffective at these low amps.  Plus low precision.

I assume the Chinese companies would use the powerwerks gauge and the adjustable load bank just like I have.

They make a 10 amp unit if wanted also.

Versus a remote load?  Like a light  bulb?

Way more accurate and with the gauge it shows all the data.

Not for everyone it seems.  Versus measure  voltages?  This would seem a more accurate way to measure any batteries actual condition

Quote Selected

Re: Load test setup

Reply #3 – September 20, 2019, 01:09:39 pm

Ok if you say they are safe I suppose.. it's the curious Cat in me that will wonder?

Is there a UL sticker on this or is it ok to overlook it on this contraption because of certain needs at the moment and the cost associated with it?

Or did I miss something?

Quote Selected

Re: Load test setup

Reply #4 – September 20, 2019, 04:33:46 pm

does not seem to be an appliance?  No  input power cord.  You furnish your own wiring  and external 12volt UL power source.  No output.

Quote Selected

Re: Load test setup

Reply #5 – September 20, 2019, 05:38:37 pm

I thought the boards and whatever transferred the current had to have the spark protection? No? Just the power source should be UL listed? Thought they tested the package not the plug.. thanks for clarifying

Quote Selected

Re: Load test setup

Reply #6 – September 20, 2019, 06:47:40 pm

Good points.  As the tester has no actual use other than to run down a battery a controlled amount and it's operation requires a separate power supply to run its board and its fan with less than 1amp it seems fairly low key.  If I disconnect the listed power supply the unit shuts off totally.  If it's power was from the battery to be run down maybe that might be different.  It only uses .7 amps of 12volt. 

Pretty safe idea that if the power is shut off or the circuit board blows the fuse everything stops.  Not powered from the batteries it's testing unlike a carbon pile load tester. 

Quote Selected

Re: Load test setup

Reply #7 – September 20, 2019, 08:16:35 pm

What if it was to back load or reverse polarize ? What would keep it from happening? Think there are certain criteria's that are followed by reputable companies .. wouldn't know about what you bought but those protections regardless of amps I thought would be important..

From what I understand .. those inspections and testing is pretty important to most .. not sure I would chance it.. short a battery out and what what happens .. you have no recourse when the product comes from outside the USA ..

Depends on what's important to you and your safety

Quote Selected

Re: Load test setup

Reply #8 – September 20, 2019, 09:13:53 pm

Terminals on the back edge are clearly labeled plus and minus and volts and amps. Plus a wire diagram was included pointing out exactly where to wire this.

Am I mistaken in the idea that most inverters will fail if hooked up backwards?  Big warnings?  That they are not polarity protected?

I have used my units repeatedly to totally discharge my two power generators.  695 watt hours, 55 amp hours each exactly.
Li ion p batteries in the units.


Interrupt the .7 amp 12 volt in and everything stops. 

Coach next.  Easy to do if you have a 12 volt plus or minus .5 volt power source to run the unit. 

Two batteries at once.  Need them to run down to 50% side by side just to see how close they are to each other and original specs.  Ran down both my power generators with the two testers then recharged both of them and swapped the gauges and the load cells and they both showed identical results.  Did it again both ways just to verify things.  Charged both units side by side and both were identical in charge times from 12 volt at 10,0 amp draws. Started out at 13.42 volts no load each.

Will do the coach batteries the same way.  Full charge.  50% discharge.  Full charge. Switch load cells 50% again.

Anderson powerwall connectors silver internal contacts should lessen any circuit differences.

Solar is in float at 13.6 volts now.  Lock out the engine batteries then pull the cables and plug in the already mounted connectors and set for desired load. 

Sounds easy..,

Need two sets of flag terminals to mount the Anderson connectors to to put on the batteries after cleaning the bare posts.

Quote Selected

Re: Load test setup

Reply #9 – September 20, 2019, 11:32:25 pm

Sounds to me you have put this thing to use and so far it has done its job?

How are the reviews? Good ? Bad?

How is the company with regards to communication and warranty if you have a problem?

Do you speak Chinese (whatever form they have in that part of the country)?

Do they have local people that can look it over if there is an issue and it starts acting up?

What would be protocol if it stops working? Do they have a 1-800 number or customer support?

Can this be used in the coach or are you using it in the house only? Garage?

Did it come with an operators manual ?

What does the safety pamphlet say in general ? Is it in English? Can you actually decipher what it says?

Sorry for all the questions.. wondering what you actually got for the money and it didn't come with any type of safety stamp/seal/label/sticker

Not sure I would use it without some sort of STANDARD.. in regards to build quality and safety measures where it has at least been tested by someone with a phd ..ADHD or whatever to know it is just a little safer than something I had put together with parts bought off the internet..

What Protections are provided? Seems a little sketchy looking at the pics.. and from China to boot.

Quote Selected

Re: Load test setup

Reply #10 – September 21, 2019, 12:32:51 am

Funny enough the first one was partially  broken in shipping.  They asked a Lot of polite questions then sent a replacement unit at no charge and told me to keep the original one.

The 4Patriots power generator  I was using the unit to test has an issue that they would not run a 5 gallon per minute rv water pump. The power generator states it will put out 20 amps from its Anderson Powerpole plug.

Pump pictured would not start with no water in it. 

Rated at 18 amps start up and 9 amps run.  No go.

So 4Patriots sent me a second $2k unit on my word.  No charge.

Ordered 2 powerwerks 25 amp power supplies to run the 2 pumps I bought to move water around and pressurize the house or coach.  Nice stuff.  Ham radio stuff.  Anderson connectors or rear panel wire connections.

Ordered the load bank after days of calls and searching to be able to test the 4Patriots actual outputs by a precision machine.

My guru buddy and I tested the two power gens together and at 20.5 amps they shut off the outlets power instantly.

The cigarette power shut off at 10.5 amps instantly also.

Seems the unit will power a resistive load but not a locked rotor motor close to its setting limit.

So using a unit to test the load cell seems like a no brainer.  If it shorts or fails the power gen shuts the load off nearly instantly per our testing of two units switching the parts between the two systems 4 times.

Of course I had two halon extinguishers and a flame blanket handy and mounted the small load cell on a fireproof surface and monitored them continuously from a safe distance where I could see both units readouts and the power gens panels at the same time.

As I spill more money than this at times a $70 purchase that turned out to be $35 due to the distributors courtesy is not a personal problem if it did not work out and I tossed it.

The power generator has a 1800 watt inverter built in that indicates its actual 110 volt consumption that we could use with a heater and calculate the batteries capacity by timing the 90% efficient(alledgedly) inverter side.

But running the load cells on a self limiting circuit in a safe area with close monitoring and with all Anderson Powerpole silver plated connectors rated for 45 amps with 8 gauge multi strand wire connections seems at least partially safe.

Tested them at a full 20 amp load twice each. 

Tested them twice a 10amp loads twice.  Then switched the load cells and tested them again twice each.

As I am an a#&l tentative, left handed Virgo, Mensa member  There is almost no detail I do not enjoy figuring out.

Remember this is prepper serious stuff to us.

The load cell distributor offered any help I needed including arranging questions answered from the  Chinese manufacturer but alas they have no English manuals nor are they needed.

Small box you hook up a approved power source to and use correct color coded connectors to the very largely labeled attach points and if you get lost you could look at the enclosed large picture showing the place to attach the wires to.

Seems pretty safe using a load limiting battery bank into a load cell that is separately powered by an approved power supply but what do I know.

If they or anyone ever releases  a UL listed small load cell I would, of course,  dispose of these units and replace them with a safer unit as anyone should.

Hope this helps anyone with a good cheap way to accurately test their own batteries.

I especially like the powerwerks made up plug and play wiring.  As I am not color blind the bright colors lessen the idea of cross wiring. 

Of course I verify every connection with my Fluke meter just to have belt and suspenders.

You never know maybe inside the connector the wires are reversed.  As both sides are separate it would be hard but....

Quote Selected

Re: Load test setup

Reply #11 – September 21, 2019, 02:40:36 am

Bob, thanks for finding these low cost battery test components and detailing your setup.  As expensive as batteries are, no need to replace them unnecessarily or trust a battery without knowing it's condition.

Something I learned along time ago: in order to improve, we must measure.

Congratulations on being able to ignore others that try to make themselves feel better about themselves with their "superior " knowledge at another's expense.  I believe sarcasm is not funny to the receivers of sarcastic comments.

And thank you to those with superior education and knowledge for sharing with us less formally trained in expertise, we need you to keep us informed and safe.  Also never not value field experience as all will not happen in the field as it does in the lab.

To end with a little humor:  This will be my last post, that is till the next one.

Quote Selected

Re: Load test setup

Reply #12 – September 21, 2019, 10:53:16 am

So Bob .. sounds like you don't trust it as much as I don't if you have a fire suppression system and a fire blanket next to it.. kinda my point..

Thanks for the replies and answering most of my questions.. think we left a lot on the table to discuss in regards to the safety and the part of the world this product came from..

Jack I also find it great for discussion that he is testing and trying new or even old products..

Call it what you want .. but superior knowledge isn't a word I would ever use to explain any parts of my post.. I was lucky to graduate high school ... believe it or not I use auto correct sometimes for the words bigger than 5 words..

This questions make for discussion .. sometimes the discussion Others will not totally understand even though I think you at least picked up on part of it..

These are merely questions that have already been asked for the most part in one fashion or the other in our continued quest for information ..

We talk up some very very good quality products on this forum.. it always goes to safety and the accompanies stickers or stamps or whatever..

This isn't one of those product a witha brand name that can be trusted as much as those we have discussed before.. If you think it to be unfair to speak of these Chinese product off the bat as some wonderful all purpose safe and reliable product without a little consideration in the area of safety .. well that's another conversation I guess..

For a guy (bob) who has been in the burn unit I am fascinated on this product and how he would actually use it not outside but inside the house. Knowing from what I have seen from China .. some things I would trust and if you looked around the house I am ire you would find a lot of things ..

Again... since I am the only one up to this point that has asked questions ... just trying to get to the bottom of the story .. like others do when we peak their interest..

I have seen a battery blow up first hand and I have had to remove batteries that were swelled and breathing harder than my wife after doing dishes.. NOT SAFE!! This situation can cause a real problem if all the planets  align ...

So I feel like bob does about safety ..

Thinking about ordering one before the tariffs kick in so I don't have to pay any extra.

Seeings how these do not come with any type of safety inspection stickers or stamps or labels is what kinda throws me off in regards to OP..

Maybe it's safe.. maybe it's not but he made a choice based on certain conditions that he feels have been met.. whether it was cheap to purchase.. he liked the company... he couldn't buy this in the states? Or whatever.. If it came from China I can put money on a couple things ..1 -the best parts are not used.. 2- it probably does not have any safety mechanisms built in...3- is not fire rated and probably wasn't built with any type of special fire rated components .. it's a safety thing.. some people get it and others don't..

As they say better safe than sorry.. no way would I have that in my house 1- my wife would have a fit 2- once the battery hits critical mass it might mess up my carpet, then I will be mad 3- if it hurts my dog then my son will be mad and last but not least if I was to n the house down 3- my grand daughter won't have a place to stay when they visit!!! Then I will really be upset..

Anyways call it what you want Jack but please if your going to refer to me as anything (again I am the only poster to thesis topic) please don't paint me as smart or educated.. we haven't met so to put a label on me like that will cause a serious problem down the road if we ever meet.. I am not smart nor educated .. live-in the big city and have a 9-5 job.. ok sometimes it's 7-6 or so but I digress.. I DO NOT want you to be disappointed in me on my lack of education.. I do not typically read unless the book has a lot of pictures. I need somethings to be visual to keep my interest .. that's why I love my Fortravel .. she is a beauty to look at and work on.. when I get bored or just flustered I grabs chair and a cold water and sit on the concrete next to her in the shade and just look at her.. she makes me happy even when I am frustrated .. she is my mistress!!

I agree with Jack.. this will Be my last post on this subject or more .. until later..

Btw I have seen some great products based out of the Netherlands that have proper store for this dance.. also have seen quality products from other areas of the world USA included.. they all seem to work one way or the other.. some longer and better than others .. some not so much.. but I give quality to them that are able to obtain that little RIVA sticker or such .. quality is not just in a sticker as I used to get those in 3rd grade and they didn't mean much at this age now..

Thanks for reading

Quote Selected

Re: Load test setup

Reply #13 – September 21, 2019, 12:07:48 pm

Do not read anything extra into the extinguisher mention,  keep a lot of things as far as fire stuff around always. The extinguishers and blankets are always in that area,  that was more of a joke,  sorry to not label it as such.  In 1986 I was in the burn ward for 16 days from a home propane fire accident.  We keep two halons and the same fire blankets to allow our exits in the coach. 

I take after Mr,  Fore as to most foreign produced stuff.  When I asked him he said "bob my customers are American, so I buy American where I can."

Quote Selected