Hello everyone,
I am considering using a smps for a guitar preamp.
I never did it before I usually use a linear power supply in all my builds.
My question is:
If I feed the smps 12vdc from a laptop power supply I have no ground wire coming in.
How do I ground the whole thing and keep it safe?
Thank you
Glass painter
I am considering using a smps for a guitar preamp.
I never did it before I usually use a linear power supply in all my builds.
My question is:
If I feed the smps 12vdc from a laptop power supply I have no ground wire coming in.
How do I ground the whole thing and keep it safe?
Thank you
Glass painter
Either the 12V supply is floating, or its -ve output will be at earth potential. In the former case you're safe anyway, but just use the 12V ground as ground.
It's preferred to use a SM supply that is earthed rather than floating as SMPS's leak a little current at the switching frequency which can usually be felt if the output isn't earthed, and you don't want to be passing switching frequency through the amp.
It's preferred to use a SM supply that is earthed rather than floating as SMPS's leak a little current at the switching frequency which can usually be felt if the output isn't earthed, and you don't want to be passing switching frequency through the amp.
Hi Mark,
Thanks for the reply.
Only in safety terms, would it be safer to run an earth wire from the input connector to the laptop PS and connect it to the case of the preamp?
This way any problem inside the case will trip the safety.
What do you think?
BR
Glass Painter
Thanks for the reply.
Only in safety terms, would it be safer to run an earth wire from the input connector to the laptop PS and connect it to the case of the preamp?
This way any problem inside the case will trip the safety.
What do you think?
BR
Glass Painter