A question for u electronics guys

**paintballgod** · 05-18-2005, 05:03 PM

This is kinda off topic with carputers but i have been reading this forum for a while and have built my own carputer and learned alot so i think u guys can help me out

. OK, i have a viper 771 XV remote start/key less entry alarm, i want to use the negative accessory output (the one used to pop trunk) to activeate a latching relay and then it will turn on neon underbody lights. With it all hooked up in the car WITHOUT the alarm as a signal it works. but if i hook the channel output from the alarm to the relay it cuts on for a second and back off. I have a guess that the alarm is sending 2 pulses instead of 1 and cutting the relay off. Any ideas? I appreciate any help you can provide me.

**scott_fx** · 05-18-2005, 05:12 PM

sounds like it's just a momentary pulse, the relay you have most likely needs constant power to stay switched. I think you need a latching relay

http://zone.ni.com/devzone/conceptd....256F1C006B7124

**paintballgod** · 05-18-2005, 06:36 PM

I do have a latching relay, thats what i think is wrong the alarm is sending 2 pulses instead on 1 to turn it on. So it turns on but another pulse turns it back off.

**paintballgod** · 05-18-2005, 07:38 PM

just tested the output of the alarm and its -.3 V the LATCHING relay requires .8 v....so its not enough to fully latch the relay, just pop it on then off.

**paintballgod** · 05-21-2005, 08:35 PM

Anyone know how to increase the voltage or know another way to set the relay off?

**BAF** · 05-21-2005, 08:49 PM

hook it to another momentary relay that can trip on/off to pulse the latching relay on.

**numbers** · 05-21-2005, 10:30 PM

It measured .3v? What was that in reference to?

**SickVette** · 05-21-2005, 11:02 PM

Which wire are you hooking it to on the alarm...what color? If I know the color I can look up that wires function and should be able to tell you what to change. I have never had a problem with latching relays on a neg out from a Viper alarm...something is odd.

**albysure** · 05-21-2005, 11:04 PM

in my viper alarm i have 2 channels to play with . one is a momentary output. the other is a user switchabe. you can choose between on as long as you hold the button, click on and click off-which is what you need and 2 others.

i'm sure a viper installer can help you out

**dmcdlrn** · 05-22-2005, 10:14 AM

use another relay... have your negative trigger close a bigger relay which has a direct line to ground. Then connect your latching relay to that bigger relay. That should be enough to trigger your latching relay.

hey albysure, I see you have a laser... I looked at one of those once, it was a really sweet car... yours have the turbo II? I had a lebaron with a turbo II and it was fast, but it blew itself up like three times.