Thought that had a safety system to stop that happening

I like the music in the background, good addition to your videos 👍🏽

What kind of batteries are you charging. If they're not lead acid with internal resistance that list the charge rate, you can over heat the alternator. I saw another video from another guy that had a system on his boat with Lithium phosphate batteries. The batteries had the ability to take charge amperage rtes in excess of what the alternator is normally designed for with lead acid batteries. Effectively the alternator the batteries will take everything and anything that alternator will put out beyond its rating because there's no limiting factors to regulate the amperage flow. You'll have to limit the alternators speed to keep it within its engineered limits of amperage output either by engine RPM or by changing pully size. if your wanting to exceed the alternators normal max amperage rating your going to need some serious cooling or it'll burn up. Change the pulley sizes to give more torque at the alternator and limit the alternators speed to keep its output close to its max output. Get a higher rated output alternator if need be and make efforts to increase the cooling to the internal windings if you want to exceed the ratred output for any alternator. look around for that vise I mentioned. I don't have it off hand at the moment

Dude!! Its going to keep happening until you change the gear ratio. That gear ratio looks to be 8 engine 1 alternator.

Thank you for your comments, much appreciated. Yes I did find I had to remove my earth neutral plug, I just need to remember Thanks Richard

Yes do make sure you remove that plug when you switch back . It would be a N-E fault . Inverters and generators deal with earthing in strange ways . The ups on my desk operates floating (i.t system) as does my portable generator . Some inverters have center tapped earth (50% l-N voltage) . There are lots of youtube vids on this subject (earthing of generators and inverters) please view them and also check the installer/user manual of the inverter . Edit mark the sparkie alison has a resent vid on this .

what kind of fuse is it for a 100/30 :/

15hp- about 11.5KW. no alternator will deliver more than half the power driving it. i saw 5-6KW. jacobs law. once the load resistance falls below the winding resistance of the alternator, thats it. more current flows through the alternator, more POWER dissipated in the alternator than in the load... windings overheat from IR2. its really simple, but its also highly overlooked. a strain gauge and a tacho and you could calculate exactly how much power is being consumed by the alternator... ie, throw a set of scales in the tensioner and calibrate to ft-lbs or something... a battery isnt a resistor. seems obvious, but its worth keeping in mind. lifepo4 charges at 29V. lead acid charges at 25.8... and the alternators regulating at 27, as it should. the low battery resistance wants to pull more current, but the voltage regulator wont let it. you really want 30V at least, "power to spare". being a cheap alternator, i doubt its any different to a 12v other than the regulator. i would be surprised if its wound any differently. rip out the regulator, tickle the rotor (field) with a variable voltage, watch the output climb... and someone mentions a large motor pulley. that actually makes sense, but not at first glance... the alternator spins faster, takes less torque to spin whilst producing the same power as volts is based on how FAST it cuts magnetic lines of force. at low RPM, it takes more exciter (field) current, and produces more lenz reaction or back torque, whilst having less EMF to produce or push that current through a load. sorry, but all YT has done in this "age of information" is give people the idea that all of this is simple, whilst busily ignoring certain critical aspects that you only find out about when you actually attempt to do something "simple". then you do a google, find nothing. getting fed up, you visit the library, and find nothing in all its shiny modern literature. finally you visit a second hand bookshop, a thrift shop... and open all those old yellowing books from a century ago and lightbulbs start going off, as they delve into subjects youve never even considered before. "wave a magnet past a wire and weve created power!" if only they knew just how more complex than that it really is.

That alternator never saw 150 amps during that short event and I think it is working as it should. What I don't know is what you are doing with 150 amps and do you expect those 8 or 10 gauge cables to actually deliver 150 amps continuously to something? They won't. Not for long anyway. The easy way to test the alt output is to put a battery tester on your batteries crank up a 200 amp load and see what your output from the alt is then. I suspect your system is good once you build some 4 gauge bolted cables.

There is no way you can stall that engine with a 150A alternator. You have to be over volting the stator and in effect creating a mechanical brake. If this is a self reg alternator and you are over riding the regulator, you may well over charge the batteries. the charge needs to be tapered down over 80% Charge. If you blow full power into them you will damage them by over gassing which may distort the plates and over heating. Don't try to get the alt to put out all the power all the time. With lead acid batteries of this type you want to limit the max charge to about 40% AH capacity. In other words, 200AH capacity total, 80A max input. when they are above 80% Charge, then that drops down to 10%. Don't over cook the batteries.

Mate I highly doubt you have damaged the alt or if you even connected it backwards long enough to do anything. The alt is not a constant output. It will taper the charge off to the battery voltage as it charges. You would only come near 150A if the batterys were flat or you had something like an inverter drawing power and pulling the batteries down. The rest of the time they will just try to taper the output to what the batteries need. If it's still doing 40A, I'd pretty much guarantee it's fine. Those alternators are tough and it takes a lot to kill them. Discharge the batteries or put a 100A load on them and I'm pretty sure you will find the thing puts out plenty of power.

Hello. I have some solar but I am looking for a way to charge the batteries on sunless days. My question is would it be better to build something like you did, or buy a generator and battery charger?

Hi. Very nice movie. The alternator is probably a poor solution. You can use some BLDC motor. For example, an alternator from a hybrid car. Alternator from Hyundai Kona Phev. You will get much more power. You will need a 3 phase rectifier bridge and an MPPT regulator. You have to be careful as the voltages are much higher.

8 inch pulley for engine

Is this more cost effective and efficient than buying a pre made generator? 🤔

I don't have a victron but I'm about to get one, thanks for sharing. You definitely know your way around soldering.

WHy you use this uneffective fuse ? It is slow so do not protect FETs, It is small, so it is hot. So tell me why use this uneffective solution, if we have much quicker and effective protection of circuits like this ?

Reference other youtubers work, don't take it as your own

The blue shmoo inside is for vibration, these are intended for mobile applications, stops the heavier components from fracturing the solder joints 👍

The blue stuf is just potting epoxy, just to keep large components in place and has no thermal function at all.

Hi, this was set up to test the alternator to make sure it was working. The plan is at some point to modify the alternator to put out a higher voltage, to use for a different purpose.

I already did this, but I used direct coupling to the engine. I have a 2 stroke set up I've not yet finished.

Great setup there mate. That's what I am hoping to build. I have a horizontal shaft lawnmower engine, so the setup would be different to yours. I like the frame you made for it also. That has given me some ideas. I like all this sort of stuff. New follower. 👍👍👍

that works fine but you're putting too much load on it. its a 2.6kw alternator on a 2.6kw engine, its never going to work with a 3kw load tester. what are you even trying to power with it ? you give no info on what its for?

Hi, a suggestion, go to a motorcycle wreakers and get a motorcycle engine. You could get a two or even a four cylinder. Much better than those shonky Chinese pull start engines. Better still get a smashed bike. You will get the engine, exhaust, fuel system, ignition system, starter (beats pulling a rope) and a whole bunch of other bits that may be helpful. Front end and frame might be bent but your going to be pulling it apart not riding it. It will be much more powerful and reliable than a Chinese lawn mower. Sound more pleasant too.

I guess if someone is in a pinch this would make for a great generator build in a couple hours or so. Love it.

This page shows a pinout for what looks like the same alternator: (YT doesn't like my link; search for "alt-b008-bosch" for a pinout) Once you have those wires hooked up, you can check the studs for output...I'd expect B1+ to be 12/14.4v and B2+ to be 24/28.8v That mower engine should be able to put out about 92A @ 14.4v by my math, if it was healthy, assuming it's gross HP rating is over-rated by 15% and the alternator is 60% efficient. (Yes, they're that inefficient). Is that a 100A battery load tester? Theoretically a bit too much for it, though you'd think the battery would make up for what's left. Cabling is rather thin for that kind of amperage, especially with that little alligator clip on the end. Unless it's the magic of video making it look small. Should be 4 gauge or lower. Might not make much difference for short bursts, but it might be making the alternator work extra hard by not having enough voltage on the field coil...but don't quote me on it; I always over-build. Let's blame the clapped out engine for now. ;-) a fresh 15hp should do the trick; my math puts it in at an engine rated at ~11.5HP, wheras if the alternator was,s say 90% efficient, you'd only need an engine rated at 7.5hp. Have a look at Hyundai Altermotors from a ~2013 sonata hybrid, especially if you're able to use higher voltages, should net you atleast 90%. Edit: Your MPPT appears to be good for up to 100v, so the hyundai altermotor should be a good choice. They run at 1350rpm @ 40vdc, so aim for twice that RPM or a bit higher...50A @ 96v should be easy for it, more amps is probably fine...they're liquid cooled, so no big deal if you up the amps a bit more to make 5000w+ output. Have fun!

Ahh, the joys of LiFePO4 and separate batteries to boot! For LiFePO4, I suggest you use an amp-hour meter...no way to judge the SOC by voltage, except when the battery is about to die or just topping off. I've only used hard wired ones, but you can probably get a wireless one these days. Just make sure it monitors both charge and discharge, as the cheap ones only do one or the other. Top charge both batteries to exactly the same voltage and forget about it...at least if they have identical internal resistance. Which they probably don't... They make balancers for 12v batteries in series, but I don't see ones meant for 24v batteries, at least in a quick search...if you want to automate the balancing, on the cheap, I suggest using a voltage-triggered relay circuit that will dump power to a dummy load (light bulb) when one battery or the other gets fully charged. That way it will trickle down the full battery and give the other one a chance to top up without you intervening. Search Ali-X or Flea-bay for "DC 9V 12V 24V Digital Voltage Control Relay Module Relay Switch Control Board Module LED Voltmeter Charging Discharge Monitor" - doesnt have to be that exact one, but that should do the trick. $5 each; you'll need one for each battery. Resitance/top balancing is what cheap BMS's do anyway, rather than active balancing. IF you see both dummy loads going at the same time, you know both batteries are full. If you have a generator running, you can use the same outputs from both modules to activate the kill switch on the engine, using two more relays with the output on them in series with one another and the kill switch ground. Yes, I find work-arounds for being too cheap to buy the fancy stuff! Hope that helps.

Nice, finally a simple video, I'd like to see how your 15hp engine performs.

Will a Bluesolar MPPT 100/30 come to part the same way,It does not have the 4 side screws. Cheers Bob.

Sad it was out of it's 5 year warranty!

Nice job! Ordering a fuse now. Mine is working with temp fix.

Great video. You helped me fix mine. Thank you. I did not open mine all the way just for now soldered a wire to the fuse to test! 😀

Hi , I also had this issue, I bought 4 x 12v 560ah , and I first noticed when my solar watts dropped out but the battery was 83 percent as yours , did you raise a complaint with fogstar and how did you get on? They just ignored our emails at least 5 of ,shocking customer service, however it does seem like the battery's have settled down now but I'm still sceptical on the issue, has this happened since or still happening with yours ???

How did you open it?

Good stuff, I did notice a piece of debris shoot into the cover from when you were trimming a piece of metal ,maybe it was jamming the cover from seating the first attempt ,you can see the debris piece fall out on second fitting 👍

What a butcher! People get themselves in such a mess with this stuff not knowing what they are doing! They have clearly made a fundamental error by either way exceed the 100 volts imput max or the have the solar connected without the battery power to run the controller! The controller must be connected to the battery first! You can send it back?! They have a 5 year replacement warranty with an option of 10 years. Even if it's out of warranty they will often offer you a deal on a replacement. I doubt most people have had them more than that!

Wish I saw this a week ago. I used force and broke the transistors in half. Might see if I can replace them and change the fuse. Worth a try.

The potting in the lid is not there to stop you opening it (it clearly didn't stop you opening it, 🙂) it's there for three reasons: 1) To improve the thermal transfer coefficient between the power electronic components and the ambient air 2) To mechanically restrain the large heavy parts like the inductor and smoothing capacitors from vibration 3) The prevent the switching parts from audibly "Humming" and a lower harmonic of the fundamental switching frequency

Why do it yourself when you have a 6 year warranty...

I would have left the fuse in the unit. Then add two wires to the outside and connect the fuse outside of the unit.

I'm going to see if this works on a 250/85 as well. Thank you for sharing this knowledge :)

Well done!

House burnt down...

Hi, last year I showed how to remove the top with the heat method, and the temperature, cheers kzbin.info/www/bejne/pKvCn4WCjrGcsMU

Hi, I did add a short clip at the end of the video, but it is no longer there for some reason. The answer is yes it's working just fine..

Hi.its been more than 8 days but no update.is it still working?

It's not as dangerous as it may look, and the system isn't finished as yet😊

Unbelievable. I really don’t like to criticise but have you made a Will yet?

Hi Did you just use 22mm copper as your heat exchanger?