Page 17 of 141

Re: Powerstar W7 Inverter modification

PostPosted: Sun Oct 13, 2013 7:09 am
by brucedownunder
Primary winding 25mm cable.JPG
Primary winding 25mm cable.JPG (38.23 KiB) Viewed 4583 times


Hello friends,,

I've sourced the heavy thick cable ,25mm earth cable , that Oztules has used for his W7 mod.

I've wound about 9 turns, and it's driving me crazy.. It's so stiff and springy.. the next apparent problem looks like it's too thick and bulky to get 30 turns ,side by side in the core..

So, questions.

does it really matter if a few of the turns cross or lay on another in the core ,the outside will be fine ,plenty of room there.

The reason for the earth cable is it's insulation is thin. Other 25mm cable has thicker insulation .

any suggestions would be appreciated, thanks

Bruce
Primary winding 25mm cable.JPG
Primary winding 25mm cable.JPG (38.23 KiB) Viewed 4583 times

Re: Powerstar W7 Inverter modification

PostPosted: Sun Oct 13, 2013 7:31 am
by brucedownunder
Opps, I just had a look at Oztules mod pictures .. Yep, there are a few turns on top of other turns ,so it must be OK .. Sorry for that ,should have looked yesterday ,instead of thowing rocks at the cat ..just joking ,we don't have a cat ...lol.

next time I do this sort of thing ,I'd buy welding cable and strip off the second (outer) insulation .. would be so much easier,very flexable.

Thanks

Bruce

Re: Powerstar W7 Inverter modification

PostPosted: Sun Oct 13, 2013 7:54 am
by Garyho
If you go to a motor rewinder they will be able to supply the proper wire that has a much thinner insulation.

Re: Powerstar W7 Inverter modification

PostPosted: Sun Oct 13, 2013 8:05 am
by Gordon-Loomberah
Normally lacquered wire is used in transformers, which has very thin insulation. The insulation on that earth wire may well cause a bit of inefficiency, and if it gets hot, you'll have a big mess.
You really want some soft-drawn copper strapping for that job, it is easy to bend, stays put, and you could laquer it yourself if you cant find any already laquered.

Re: Powerstar W7 Inverter modification

PostPosted: Sun Oct 13, 2013 11:20 am
by Tracker
.
Could you have got "Proper" transformer wire..
Yes - RARE - Stiff - but thin insulation..

You could wind it with string, to get the length and then just buy THAT length from someone who makes transformers (Rather than a massive roll..

I would use a rubber mallet to tap each turn into shape as it goes on..
Then when complete , a few coats of ISONEL (do I remember it right) to improve the insulation..

( Sorry - just noticed the other posts - Same-Same )

PS - Now here is a go..
Look for OLD microwaves that are LIGHT - INVERTERS - They have a special transformer for the HV (2000V), made of DOZENS of fine wires twisted like a steel cable would be - MASSIVELY Flexible.. and thus easy to use.. They are normally powering about 1000W, so the power could be in the right ballpark and you could double up in parallel.. :idea:

Inverter Wire.jpg
Inverter Wire.jpg (33.23 KiB) Viewed 4566 times


What it looks like..
..
.

Re: Powerstar W7 Inverter modification

PostPosted: Sun Oct 13, 2013 11:26 am
by davidg
brucedownunder wrote: I've sourced the heavy thick cable ,25mm earth cable ........... I've wound about 9 turns, and it's driving me crazy.. It's so stiff and springy.. the next apparent problem looks like it's too thick and bulky to get 30 turns ,side by side in the core..

That's a really hard way to go. There is another way, you use thinner wire and wind several lots of it on, then parallel the outputs together to ramp-up the current output, make sure you use the correct lacquered wire, and get it even around the toroid BTW there are different temp ratings for the wire use a higher temperature version.

brucedownunder wrote: does it really matter if a few of the turns cross or lay on another in the core ,the outside will be fine ,plenty of room there.

No, but like Gordon said heat is an issue and the transformer will almost certainly exceed the rating of PVC insulation pretty easily.

brucedownunder wrote:The reason for the earth cable is it's insulation is thin. Other 25mm cable has thicker insulation.

Not true all "building wire" for the mm2 size has the same insulation thickness, "earth wire" is more common at those sizes because it's used from the switchboard to the main earth stake regularly.

Re: Powerstar W7 Inverter modification

PostPosted: Sun Oct 13, 2013 1:19 pm
by brucedownunder
Gee, it's nice to hear the experience you guys have .

I'm perservering with the Oztules earth wire method ,she's getting better. I'm using a soft hammer very effectivally around the bends and flats,the inside will just have to cope with a bendy curve,it's not too bad.

13 turns so ,there will be "inner" turns piggybacking and laying side by side in a few turns. This will be sorted out evenly after all the 30 turns are completed and secured.

Thanks for all your thinking ..

Bruce

Re: Powerstar W7 Inverter modification

PostPosted: Sun Oct 13, 2013 1:26 pm
by Tracker
.
Just don't forget the temperature rating of the wire -- Likely v75..

I have felt running inverter trannies and they may have got close to that 75..
So don't be adding tape insulation over the top and that will concentrate the heat..

The Selectronic type devices incorporate temperature sensing to ensure ratings are not exceeded..
..
.

Re: Powerstar W7 Inverter modification

PostPosted: Sun Oct 13, 2013 1:49 pm
by brucedownunder
Thanks for the temp. advice.

Do any of you know if I can place this transformer in an adjacent steel container,only a half mtr or so away ,with ,say,very heavy battery cable for the fly-leads ?? just a thought.. and a fan , temp sensor ,etc.?

Bruce

Re: Powerstar W7 Inverter modification

PostPosted: Sat Oct 19, 2013 6:40 am
by ShaneG
Hi all, first post, new member - problem:
Powerstar W7, PS2024E 3000W 24VDC.
The unit is miss reading the input voltage coming from the generator and therefore not engaging the charger circuit. Example - Honda generator is outputting a constant 230VAC (Checked with 2 meters) - PS W7 detects this as 286 VAC and therefore out of range.
My question is this, is there ant way to adjust or trim the input voltage reading that the W7 is sensing.

If you guys can't help me then it's an anchor!

Thanks

Shane