How to ground the case of a multiple output power supply?
- The G
- Grease Monkey
I started to make a power multiple outputs, an "eco" one (see pictures). It will feature 4 9V DC outputs and one 15V/18V or ±15V/±18V (not decided yet), using reclaimed transformers and LM317 regulators.
My question is: do I connect the case to the ground? If yes, which one?
Thank you.
P.S. I know I have to reinforce and isolate the case. Will do.
My question is: do I connect the case to the ground? If yes, which one?
Thank you.
P.S. I know I have to reinforce and isolate the case. Will do.
- mysticwhiskey
- Solder Soldier
Assuming you're powering the transformers from the mains supply, then the case should be grounded to the main's earth for safety. Don't forget to add a fuse too. You don't need to ground the regulated DC outputs to the case, and in fact it's desirable not to if you want isolated outputs to prevent hum from any ground loops. Use isolated DC jacks if this is the case.
- The G
- Grease Monkey
Thank you.
I thought this might be the answer, problem is that in my country only mains sockets with earth are in the kitchen (overpopulation control? who knows...). I don't play in the kitchen, which means no shielding. Is there anything I could do in this case?
I thought this might be the answer, problem is that in my country only mains sockets with earth are in the kitchen (overpopulation control? who knows...). I don't play in the kitchen, which means no shielding. Is there anything I could do in this case?
- Hides-His-Eyes
- Tube Twister
Pray for your safety...
I don't think there's much you can do. Leave it ungrounded. Better yet, insulate the inside with some kind of firm material that won't easily be nicked by a wire. Or better yet indeed, build it in a plastic enclosure.
I don't think there's much you can do. Leave it ungrounded. Better yet, insulate the inside with some kind of firm material that won't easily be nicked by a wire. Or better yet indeed, build it in a plastic enclosure.
Testing, testing, won too fwee
- DrNomis
- Old Solderhand
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You could ground the DC side of the supply to the case by connecting a 100 Ohm resistor in parallel with a 100n capacitor from the circuit ground to the casing, something that is done in the current version of the BK Butler Tube Driver, also, as has been stated in one of the other posts in this thread, make sure that you have securely connected the Mains Earth wire to the case, this prevents the case from becoming live if a fault occurs in the mains transformer primary-winding, and also include a suitably rated mains fuse in the Mains active wiring to the transformer primary....
Genius is not all about 99% perspiration, and 1% inspiration - sometimes the solution is staring you right in the face.-Frequencycentral.
- johnnyg
- Resistor Ronker
I know this topic is old hat. But the best would be to try and fashion the unit as approximating 'Class II': http://en.wikipedia.org/wiki/Appliance_classes#Class_II So a solid plastic enclosure like HHE suggests surrouding some kind of metal faraday cage to help reduce any interference perhaps.Hides-His-Eyes wrote:Pray for your safety...
I don't think there's much you can do. Leave it ungrounded. Better yet, insulate the inside with some kind of firm material that won't easily be nicked by a wire. Or better yet indeed, build it in a plastic enclosure.
The household appliances you get in the UK with a plastic pin in place of the metal earth pin on the plug (and just two wire cable) used to perplex me before I learnt something about this kind of thing.
Yet to break through the Space Charge