D Vautier 6/2017
When you have to replace a T8 or T12 ballast there is usually an extra wire clip in each of the sockets so you get one chance to replace the ballast without having to splice. Otherwise you have to splice all the wires or get new sockets because once the wires are inserted into those locking holes they do not come out.
However I did discover an fairly easy way to remove the wires. I took the socket out and pealed back the cardboard from the back. I inserted a needle into the back of the clip just beside the wire. By bending the needle slightly I was able to lift the clip enough to remove the wire without damaging the wire clip. I did this for all the sockets. I installed a new ballast without trouble and without unnecessary splices.
Some sites do suggest splicing but this seems primitive especially when there are always extra wire clip-ins on the socket designed specifically for ballast replacement. Or you can have extra sockets around or you can remove the old wires with this technique.
Here is a socket with the back
off showing the wire clips.
Here is a socket with the cardboard bent back exposing the clip.
I inserted a needle and pried up just enough to remove pressure which releases old wire.