i have 4 add-on sensors for my new alarm. i have a few quick questions on wiring them properly.

+12v constant is obvious.

i know i need to add a 1amp diode to the alarm (-) trigger input for each sensor as well.

my question is on my (-) 500 mA ground when armed output. it's only 500 mA: is that enough current to supply to all 4 sensors? my guess is not, and that i will have to use a relay, and have the (-)500 mA output trigger the relay, which completes the ground. is this correct?
[edit] after further research, i found this won't work. i would have an energized relay with the car off, and it would likely kill the battery...

according to autotoys, the 500ma ouput from the alarm was enough for all sensors. i hooked them up to the GWA, and all is working fine[/edit]

second question, on my microwave sensor, there is both a hard and prewarn output. my alarm does not have a separate prewarn and hard trigger input. can i simply connect both the prewarn and hard trigger to the (-) trigger input of the alarm? my alarm has the .8sec prewarn and >.8sec hard triggers, but they're not separate inputs.
[edit]also, i did as i described for the microwave sensor, and it's working fine.[/edit]

someone... anyone, please give your input. tia


[Modified by DOHC-DX, 5:40 PM 1/13/2003]

 

You would need to look at the information that came with your sensors to see how much current they require. Or you could hook them up to your battery and use a DMM to measure the current. If it's over then yes you could use a relay, just make sure you read the current requirements for the relay.

I would say yes on your second question just make sure each one has a diode attached. This will only work if the pre warn output is less than .8sec. If your using the Clifford motion sensor I believe its pre warn is more than .8secs. So you could wire the pre warn to a relay then directly to the siren. Using a diode on the output of the pre warn of course.



[Modified by nsxxtreme, 7:40 PM 1/9/2003]

 

unfortunately, none of the sensors include the power requirements.

one is the DEI digital tilt sensor, which i know teken and others have. other ones are: proximity, 2nd dual stage shock and audio/glassbreak.

for the second issue, i will add the diodes and try it. if it doesn't work, i'll get the DMM out and try and time the individual triggers.

thank you for your input!

 

no, it's made by omega, model au94t... if that matters. i got all the sensors from autotoys. i would be asking in their forums, but i'm still haggling with their tech dept trying to get access.

 

well, i was thinking some more. why exactly do the sensors have to be connected to a "ground when armed" and not a constant ground? it seems to me that connecting to a constant ground would operate exactly the same way.

the12volt.com suggests that the sensor should be connected to a solid chassis gound....
http://www.the12volt.com/carsecurity/page5.asp

 

i say connect all to a good constant ground.....and use diodes to isolate all inputs.
now DEI used to have a diagram that would allow you to add warn away to a system that was not set up for it...it would pulse the siren for a few seconds...its an old one. the only wiring issue you would have is not having your car BARK when the alarm was off.

hope this helps..also fuse the items as well...so constant fused 12vts and ground and the triggers going to the instant trigger of your excalibur alarm ( if memory serves me well it may have a setting for warn away.)

 

This is why you would hook it to a switched output. If his pre-warn signal is >.8sec he will have to wire a relay to the output then hook it directly to the siren. If its hooked to the - when armed it will keep it from "barking" when not armed.

 

any suggestions on what rating fuse the sensors should get? i would imagine not higher than 5amps

also, the alarm is avital/DEI

 

That would be a small fuse something your not going to get at a part store. I don't see any reason to fuse the sensors.

If I remeber right I did this on one of my old alarms. Instead of hooking the - when armed to ground I hooked it to a relay. Then ran the pre-warn to the relay then to the siren. This way is still retained power when the alarm was off but didn't "bark". The reason to retain power is I was using a clifford motion sensor if it lost power it lost it's settings.



[Modified by nsxxtreme, 9:44 AM 1/10/2003]

 

well, i'm going to fuse them. last thing i want is to fry my $60 tilt sensor

 

Electricity acts a lot faster than it takes to blow a fuse. Fuses are designed to protect the electrical system not the device. Although if the device can withstand small current spikes a fuse may protect it. Since your sensors use such a small amount of current a 5 A fuse will do nothing to protect them.

I would run my power wires from the alarm, the alarm is already fused so it would protect electrical system.



[Modified by nsxxtreme, 10:31 AM 1/10/2003]

 

ANyone have problems with their tilt sensors? I have the dei 500t tilt sensor. For some reason it always goes off when it gets below freezing. Is this normal I know its a mercury sensor?? Are there any other types of tilt sensors besides mercury type sensors??

 

yes, DEI has a a totally digital tilt sensor that obviously has no mercury. it's $60 tho

 

you know the part number?

 

it's the DEI 507t

 

i also want to add, that i wired all 4 sensors to the (-) 500ma output from the alarm, and it works perfectly. the digital tilt must be connected to GWA, otherwise, it won't re-set itself every time the alarm is activated.

 

Glad it worked out for you. Have you checked to see how much current all of them are using?

I found a pic of how I was talking about wiring them.
http://www.the12volt.com/carsecurity/page5.asp


[Modified by nsxxtreme, 11:28 PM 1/12/2003]

 

no, i never checked the current. the guys at autotoys said the 500ma would be enough, so i just hooked them up.