Q&A Forum
Planning the build of a Hub Dyno with 2 Telma CC160 retarders. And if someone could confirm I have chosen the right components for the power supplies would be appreciated . Trying to keep the budget down so gone the Semikron route. The SKPC 200 240 seems to be 3 times the price of the 115Volt and 440Volt version. Therefore planning to use a step down transformer (240 to 115)
And the SKPC 200 115, with a 240Volt supply to the SKCH28/14 which I believe is rated at 30 amps, the Telma should draw max 16amps when rewired to 192V.
Thanks in advance
Hi,
I assume you planned to rewire the brake to 96V then? That's possible. (You cannot get 192V DC from 110V AC, obviously)
But you should avoid transformers, because the semikrons will turn on and off the power, which causes voltages spikes when you have a transformer. When using a transformer you would need more heavy filtering to suppress these voltage spikes. It is possible to make it work, but you risk breaking something expensive unless you get those filters in good control.
The transformer you link to is too weak, it has a VA of just 100 (i.e. max current = 100VA/110VAC = less than 1A).
Better go the normal route ;-)! Note that most people go with the SportDevices power supply, it is slightly more expensive, but it is a finished product.
Regards,
Jostein
Thanks for the reply, I was only intending to use the transformer to power the SKPC 200 and that has a very small current draw from what I can see. The power for the retarder would be direct from the 240v mains. via the SKCH 28, I have an image from the SKPC 200 data sheet about alternative power supply but can't see how to attach it as the paper clip icon doesn't seem to work
Graham
Just seen the attach file at the bottom, I hadn't scrolled down fully, so here is the image
I see what you mean. You would need to make sure the phase relationship is the same (is there some delay or shift through a transformer?).
You could ask Semikron directly, I got a reply from them when I asked something earlier. Or maybe someone else here on the forum has some advice.
Have not tested this, since i did had loads of stuff on the shelf.
But it should be similar to others!
At that price it has to be worth testing, would prefer to use European manufactured components but I do have a limited budget for this project so can't ignore this option.
Found this Bridge Rectifier on ebay too
Can anyone see a reason why it's not suitable to use
Lars,
That's a nice circuit! It looks similar to the solution from NuWaveProducts, but simpler to use and cheaper. You need a full bridge (passive) rectifier in addition, but that can be had also at a very low cost.
Let me know how this works, if anyone tries it. I will update the website with this info.
Regards,
Jostein