\What voltage diodes
Peter Bell | 14/08/2017 17:15:38 |
399 forum posts 167 photos | Am I right in thinking that 600piv diodes will be suitable for use with this voltage doubler circuit with 250v output from the transformer? Thanks Peter
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Muzzer | 14/08/2017 17:25:08 |
![]() 2904 forum posts 448 photos | Each cap will become charged to about 350Vdc. The diodes will then see about 700Vdc peak reverse voltage. You need a sensible margin on top of that, so consider 1000V a sensible minimum. Short answer - no. Murray |
Peter Bell | 15/08/2017 07:04:16 |
399 forum posts 167 photos | Many thanks Murray Peter |
Howi | 15/08/2017 08:55:26 |
![]() 442 forum posts 19 photos | 1N4007 diodes are rated at 1000v if memory serves me correctly. |
Nicholas Farr | 15/08/2017 19:10:07 |
![]() 3988 forum posts 1799 photos | Hi Howi. you are correct, and all seven of the 1N400# series have a max rectifying current of 1 amp. Regards Nick. Edited By Nicholas Farr on 15/08/2017 19:10:53 |
Brian Oldford | 15/08/2017 21:52:13 |
![]() 686 forum posts 18 photos | If you need a higher current 1N5408 is rated at 1Kv 3A |
Peter Bell | 15/08/2017 21:58:17 |
399 forum posts 167 photos | Thanks for all the input, I seem to have quite a lot of 600v diodes with a suitable current rating in stock so intend using two in series. Seem to have so much stuff in stock better try and use some up! Peter |
Muzzer | 15/08/2017 22:18:21 |
![]() 2904 forum posts 448 photos | Best to use proper bridge rectifier diodes if at all possible. They are generally quite slow, which isn't a problem at 50Hz, but also tend to be relatively large lumps of silicon. That's necessary in order to withstand the surge currents typically encountered with large bus caps and mains transients. Bear in mind that you can expect some pretty large surge currents depending on the instantaneous voltage when you connect the mains via the power switch.So although you may only expect an average current of an amp or so, your diodes should be rated for non-repetitive surge currents of perhaps 10-20 times that. If you are in doubt or don't have suitable diodes, it may be worth getting a 1000V bridge diode. They only cost a few quid from CPC. Murray |
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