My alarm panel has both +ve and -ve output for the strobe. I have brought a new bell box, but only requires the -ve to operate the strobe. I have put just the -ve from the alarm panel to the strobe terminal in the bell box but the strobe does not work. Any ideas anyone please

suke, January 2008

Just like every other electrical component, the strobe needs a + and - supply. No way will it work with only one.

John, January 2008