If you are charging lead acid batteries, you do not need the capacitor...
That is a serious transformer and I would guess that it would be capable of delivering a 10A charge into the three batteries. For the time being assume that figure is correct.2) I am not sure what the amp output of the transformer is, it is 16cm W x 13cm D x 14cm H, and weighs 9.7Kg.
Excellent- that simplifies matters no end.3) I just want to "top" up the batteries during the discharge only.
Good news! As long as you do not leave lead acid batteries in a discharged state they are unlikely to deteriorate, so the best approach is to re charge as soon as possible.4) 10 min is more than enough time for the heater to do it's job so with the transformer top up it should be enough time not to discharge too deeply.
Thanks. The 36V is nominal. The actual voltage will depend on battery charge state, current drain, and temperature5) There are three batteries in series so total of 18aH capacity @ 36V
Thanks- do you have a part number and/or a link to the manufacturers data sheet- not essential6[1]) The batteries are UPS AGM type,
Excellent- providing that the transformer charging is sorted, you would probably only need to do a conditioning charge with your pro charger every ten or so induction heating sessions. Of course, the more often the better6[2])once the heater has done it's job then I can individually charge the batteries to full with my 4 stage battery charger
Don't worry about that- it can all be fixed.6[3]) But I am not sure what the extra voltage will do to the 3 batteries, although I measured the output with no load but I just don't know what the voltage will drop down to once connected to the batteries and or the heater.
Hi Ed,The batteries are Powersonic brand PS-12180 NB 12V 18aH
The induction heater works from 12-40V, here is a direct cut and paste from a sales page on E-Bay.
Features:
The DC power supply voltage is 12V~40V.
Recommended input voltage range DC 24V~36V.
Maximum input current 50A (short), Maximum power 1000W.
Equipped with a fan.
High quality module board for induction heating machine.
Notice:
When used in heating supply power must be large enough!
24V power above the recommended maximum current of 20A.
12V power supply maximum current must be more than 10A.
Specifications:
Power Supply: DC 12V~40V
Max. Current: 50A
Max. Power: 1000W
The only must have spec is that the amperage must be instantly available from the time the module is switched on otherwise it won't be able to resonate the current through the looped copper coil and build up the large magnetic field, which is why I am using the batteries.
It doesn't take long to start heating metal, I managed to heat up a 19mm steel rod till it started to smoke in about 20 seconds before I got distracted and blew out all the modules' mosfets on the circuit board. I ordered 4 replacements and soldered them in, but one of the new ones was faulty so now have to wait a few more weeks for it's replacement to arrive.
Once that is fitted I will find out if there is any more damage to the module. If there is I will have to buy a new module, they are about $52 to $60 dollars delivered. That will teach me for not paying attention!
In the mean time while I am waiting for the part to arrive I would like to sort out the power supply.
No sweat about help.Thanks for all the help. I tried to get those mosfets from RS online, unfortunately they only sold them in in packs of 25 and they wanted about $6 Australian each, hence the reason I got them off ebay. When you pay $8 for 4 of them delivered I expect to get a few duds every now and then. As I wanted to be sure that there no other damaged components, I didn't want an expensive outlay for 25 of them not knowing if they may fix the module or not, and 21 of them would just be wasted.
I suppose I could just connect it up briefly to the 3 batteries and see what the DC voltage ends up. Is a different sized lower voltage capacitor an option?
Hmm, quite tasty NMOSFETs. There are better though.The MOSFETS were IRFP260N
That is good. May I suggest then that you forget about the transformer for the time being and go for a two battery configuration which will give you much more reliability and, hopefully, no more blown MOSFETs.The reason I was hoping to use the 3 batteries was that it was close to the output of the transformer..
That is not necessarily true.If I use just the 2 batteries I won't be able to use the transformer to top the batteries up as I use the heater.
Ah, that indicates that the induction heater is reliable working from about 36V, which is what I imagine the voltage the three batteries would be producing, with a current load of 30A (the current that the induction heater would be taking with a 36v input according to the data your post #11)The blown MOSFETS were the result of me not paying attention and Accidentally contacting the bottom of the circuit board to my steel table which shorted the lot, with lots of big sparks and and a big bang. It was working well up to that point.
We use cookies and similar technologies for the following purposes:
Do you accept cookies and these technologies?
We use cookies and similar technologies for the following purposes:
Do you accept cookies and these technologies?