S1ZB60-4072 Rectifier Bridge in series?

[fastesteddy13]

Hey Harald..
Thanks for the drawing, I do get that iron cores give a lot more power, but I did not want to have to deal with any cogging and was aiming for a more axial type.. When I scale up and make the big one, I may consider iron cores if I can keep cogging to a minimum and also find a reasonable source of soft iron. Here in north Scotland there is no shortage of wind..

Weather proofing is not an issue, discs are made from corian, the all-thread (m6) in the centre is covered in an aluminium tube, magnets and coils will be covered in epoxy and the frame it will be mounted on is aluminium angle. There will be a plastic 'skirt' arrangement on the outer part of the discs which will keep the rain out and the vanes are made from 6" rain guttering.. Also stainless nuts and washers..

Just got to rewind all those coils now.. sigh..
Reckon the cost should be around £40-£50 for this little one, objective was to make it cheaply and learn in the process.. So far so good..

 

[ratstar]

Whats the amperage, and then ull get your output watts? but uve tonnes of room for improvement with all those extra coils to add! cool.

 

[fastesteddy13]

Hi ratstar.. Was going to wind a few more coils first, but what is the best way to check amps? Pop a resistor as a load then hook up multimeter in series?

 

[fastesteddy13]

Hey Harald..
Have been looking around the net re shottky rectifiers, have come across these..
https://www.ebay.co.uk/itm/10-x-SS3...726009?hash=item1a906594b9:g:6JkAAOSwcnpdKfLP
would they do the trick?
Am I right in thinking that I could get more power using these rectifiers?

And ratstar, was a serious question about how to check amps, my (poor) understanding is that I have to put a load (resistor?) and then pop my multimeter in series to check amps.. Can you suggest resistor value?

Quickly ran out of copper winding the new coils, about 49g each x 38 so still waiting on delivery, being up a mountain in northern Scotland, I have to wait for a passing eagle to drop the post, + bank hols have got in the way..

 

[Harald Kapp]

would they do the trick?

Yes, but:

• these are surface mount, a tad difficult to use. Better use leaded diodes (cf. this selection).
• these are single diodes, no bridge rectifiers. You'll have to build the rectifier from four f these single diodes.

You can buy full bridge rectifiers made from Schottky diodes as for example this one.

And ratstar, was a serious question about how to check amps, my (poor) understanding is that I have to put a load (resistor?) and then pop my multimeter in series to check amps.. Can you suggest resistor value?

A typical way to characterize a voltage source is by open circuit voltage and short circuit current. Or equivalently open circuit voltage and inner resistance (Wikipedia).
you measure the open circuit voltage with no load attached to the source.
You measure the short circuit current with only an Ammeter (multimeter in A range) short-circuiting the output of the source.
If the short circuit current is very high or you fear to damage the source, you can also use any reasonable resistor in series and measure the current. It is then a matter of a bit of math to calculate the short circuit current or the inner resistance.
What resistor to use? It depends. Set yourself a reasonable current you expect from the source. Your coils are weak so aiming for e.g. 100 mA is imho an ambitious goal. From the open circuit voltage and the expected current calculate R = V_oc / I_expected. Of course, due to the inner resistance of the voltage source the real current you measure will be less than the expected valeu, but that is not relevant as the resistor is only there to bring the current within a reasonable range. The exact value of the current is measured, then used to calculate the parameters of the voltage source.

 

[fastesteddy13]

Thanks Harald..
Have ordered schottky diodes, also took your advice and ordered 1000uf capacitors.. Have re-wound all the coils to around 1000 winds. Just waiting for delivery and will post updates when they arrive..