Black Widow BW850 Siren

Hey I read the other thread but I am still unsure, is the blue wire a positive signal or a negative signal from the alarm. If that makes sense like my alarm puts out a positive signal so therefore would I need to put a relay in so it changes the polarity? I wired it up and everything then turned the key and it set the siren off when the alarm wasn't triggering. Can someone help me with this problem? Thanks - VnFantasy

negative signal (Blue) sensor trigger  what are u trying to dodragon

I'm trying to connect it up to My Car Alarm which says it sends out a positive signal out to the alarm. Therefore if the blue wire is a neutral signal I need to put a relay which explains why it just blasts when I turn the key on the siren rather then only blasting when needed. So the red is positive which gets connected to a fused active (so to speak), black is earth/negative and blue is also negative and grey is forgotten about?!? Yeah is that about right?

Is that a Black Widow siren?? With red, black, grey and blue? Red=Positive(constant) Black=Negative Grey= Negative Trigger Blue= Positive TriggerWOW Sight and Sound

Maroochydore

Nothing is impossible!

Do it right the first time or don't do it at all.

yeh it is a black widow B850 with the red, black, blue and grey. My alarm's output is Positive so would I use the blue or grey wire? when I used the Blue my siren wouldn't shut up, when I used the grey it wouldn't shut up! I can't work out what is going on.

Are we talking about on the Siren?!? Cos what send the signal to set the siren blasting? Red is constant charge to the battery backup. so blue or grey is the wire to tag with the positive out of my alarm brain.