Precautions to take when working with AC mains


Old 03-24-16, 03:49 PM
Thread Starter
Join Date: Mar 2016
Posts: 1
Precautions to take when working with AC mains

Hello, I am relatively new to playing around with circuits, and I have started a circuit build on a small 12V amplifier which naturally requires a plugin from the AC mains of the house. I feel confident with wiring the circuit, it is not very complex; i do want to make sure though that I am not looking over any safety precautions besides the obvious when I am building the circuit (specifically the power supply unit). Also, is there any way I could damage the internal wiring of the house when using an AC/DC power supply? Thanks for any input, I am trying to be as safe as possible
Sponsored Links
Old 03-24-16, 04:24 PM
Join Date: May 2015
Location: USA
Posts: 3,138
One thing you can do to protect yourself a little is to make sure the AC circuit you connect to if protected by a GFCI. You can even buy extension cords equipped with one in case there isn't one handy where you are working. This will protect you from being shocked should you accidently touch one of the live AC wires.

Always have an inline fuse in the AC part of the circuit, and use the smallest fuse you can based on the current the circuit will draw. If there is a metal case involved, make sure it is connected to the ground wire coming from the AC cord.

Not really anything you can do that would permanently damage your house wiring. The house circuit breaker's job is to prevent that. Good luck and have fun!
Old 03-24-16, 04:25 PM
PJmax's Avatar
Group Moderator
Join Date: Oct 2012
Location: Northern NJ - USA
Posts: 46,124
Welcome to the forums.

I started building circuits when I was around 10.
I blew up many 120v electronic items in the interest of learning.

As long as you use a 120v to 12vdc power supply..... your project is on the protected side of the mains service. Today, there are literally hundreds of 12vdc power supplies to choose from. You can select from eBay to amazon as well as a large handful of online retailers.

MCM electronics is a hobbyist friendly easy to use site that has no minimum order and has great customer service. I've been buying from them for over 15 years.

MCM Electronics: Home and Pro Audio/Video, Security and Test Equipment
Old 03-24-16, 05:31 PM
chandler's Avatar
Banned. Rule And/Or Policy Violation
Join Date: Dec 2005
Location: USA
Posts: 39,968
From the terminology used I feel the OP is not based in the US. Voltages and set ups may differ from what we have.
Old 03-24-16, 05:39 PM
PJmax's Avatar
Group Moderator
Join Date: Oct 2012
Location: Northern NJ - USA
Posts: 46,124
The OP is located in the United States.
Old 03-24-16, 07:17 PM
Tolyn Ironhand's Avatar
Group Moderator
Join Date: Nov 2007
Location: Twin Cities, MN
Posts: 12,279
which naturally requires a plugin from the AC mains of the house.
I got the same feeling as Chandler did because of the above statement.

Just to be clear, you are not planning to connect to the main breaker, or the main (large) wires feeding the main breaker correct?
Old 03-24-16, 08:25 PM
ray2047's Avatar
Group Moderator
Join Date: Mar 2006
Location: USA
Posts: 33,047
Back years ago pre solid state it was common practice to plug TVs and radios into isolation transformers for safety when you worked on them.

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Thread Tools
Search this Thread
Display Modes