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Plays_with_Toys
11-21-2005, 07:59 PM
Ok, if I want to mount several things, and run off of one signal wire, what do I have to do to make sure amperage stays the same across all the accessories? I know they will all have 12-14volts. Is this the job relays do? Thanks!

Wiscon_Mark
11-21-2005, 09:17 PM
I would also like to know...

gil_ong81
11-21-2005, 09:22 PM
you can't. unless wire them in series, but then you lose voltage.

Plays_with_Toys
11-21-2005, 09:25 PM
So how are people wiring the hella supertone horns? There's two of them, but one signal wire???

gil_ong81
11-21-2005, 09:28 PM
So how are people wiring the hella supertone horns? There's two of them, but one signal wire???

with a relay.

Plays_with_Toys
11-21-2005, 09:28 PM
Hmmm... seek and ye shall find:

relay

n 1: the act of relaying something 2: electrical device such that current flowing through it in one circuit can switch on and off a current in a second circuit [syn: electrical relay] v 1: pass along; "Please relay the news to the villagers" 2: control or operate by relay


So to wire up a couple things, you'd run off the battery, and grounded to the frame. But, run this circuit from a relay. So one signal wire to several relays can connect the signal to all the accessories. Thats how I understand it.... for the moment...

gator gt
11-21-2005, 09:34 PM
My goodness sir, how many accessories you looking to latch onto your car??

GGT

shazapple
11-21-2005, 10:08 PM
a relay is basically a 'electric switch'. your 'signal wire' will tell the relay to close the switch.

You can probably use one relay (the signal wire being your original horn wiring, and the other side of the relay is hooked to the battery and horns).

What voltage or power are they supposed to get? Im assuming you would hook them up in Parallel, so each horn gets 12V (but half the current). Hooking them up in series would give each horn 6V (and full current)

If you use two relays youd get 12V and full current to each horn. Whats the power on the horns? Power(Watts) = Voltage (V) x Current (A)

gil_ong81
11-21-2005, 10:14 PM
......hook them up in Parallel, so each horn gets 12V (but half the current). Hooking them up in series would give each horn 6V (and full current)


see what happens when you don't use it for 5 years? :oops:

Wiscon_Mark
11-21-2005, 10:15 PM
wouldn't less voltage mean a lower tone?

shazapple
11-21-2005, 10:26 PM
Yup.

BTW, put some fuses in the circuit, probably right before the horns (so you have two small fuses instead of one massive fuse)

jdmconnected
11-21-2005, 10:51 PM
Ok, if I want to mount several things, and run off of one signal wire, what do I have to do to make sure amperage stays the same across all the accessories? I know they will all have 12-14volts. Is this the job relays do? Thanks!

Actually, you've got it backwards.

The voltage will drop based on the total current (amperage) load of the devices and the gauge (diameter) of the wire. This is all governed by the value of the fuse on the circuit of course, if you pull too much current it will blow.
When you add devices (or turn them on) each device will "take" what current it needs based on the voltage its seeing, total current will be the sum of all the devices. As you draw more current the voltage goes down proportionally because of the resistance in the supply wire. (this is based on a regulated DC supply)
The voltage drop isn't significant unless you're using tiny wires to run dc motors or similar high draw devices, or you do something else wrong. ;)

In the case of horns (and most other automotive devices), ground is taken from the chassis so the single wire is still considered parallel wiring. (this was already mentioned)

Just check the rating of the horn relay (if equipped) if this rating is greater than what the horns use (very likely) then just hook the horns up to the existing wiring and there should be no problems. No need to mess with fuses is this case either.


What voltage or power are they supposed to get? Im assuming you would hook them up in Parallel, so each horn gets 12V (but half the current). Hooking them up in series would give each horn 6V (and full current)

If you use two relays youd get 12V and full current to each horn. Whats the power on the horns? Power(Watts) = Voltage (V) x Current (A)

Hooking up the horns in parallel would not result in half the current, because the supply (battery and alternator) will provide the current necessary.

shazapple
11-21-2005, 11:15 PM
Yeah, youre right. I thought about that after I wrote it

Plays_with_Toys
11-21-2005, 11:57 PM
I'm prepping for my cadillac horn install. Cadillacs use 3 tone horns. So I am going from one horn to three. Hence the need for keeping the current up. I guess I'll just try to splice all three on one line and see what happens. If it doesn't work, I'll ask more. :lol:

Unless I can find a wrecked late 90's caddy, which uses a single megaphone style horn.

pdawg
11-22-2005, 08:54 AM
Here's a write up by Pat Olsen over on Nasioc that might help
http://forums.nasioc.com/forums/showthread.php?t=882409

Plays_with_Toys
11-22-2005, 07:07 PM
Yep, I've got a subscription to that thread. But again, thats two horns, and I will be using three. Maybe I'll try with the lowest and highest and see how it sounds.

gil_ong81
11-22-2005, 09:10 PM
my car is black. the hood is new, ~1.5 years old.

Wiscon_Mark
11-22-2005, 09:13 PM
my car is black. the hood is new, ~1.5 years old.

huh?

PWT- good luck, I want to see video clips when you're done :D

Plays_with_Toys
11-22-2005, 09:19 PM
I'm doing a video this weekend. Both with horn and intake sound clips. Plus fun. :twisted:

gil_ong81
11-22-2005, 09:31 PM
huh?



:-D

i was just screwing around