Wiring Idea

[Cerberus90]

In planning the new wiring for the Taimar, I've had an idea come about to regarding the ignition wiring.

I want to use some mate 'n lock connectors for the ignition and stalks, the ones I'm looking at have a max current of 20A. Which for the main ignition power feeds doesn't sound enough.

The idea is to have a big relay, I've found a 100A one. Power comes into the ignition switch as usual, but can be a smaller gauge wire, the ignition power out goes to the low side of this large relay, which basically acts as a second ignition switch, but removes the large power draw and large cables from the ignition barrel.


Anyone see any problems I've overlooked or reasons not to do this?

Biggest plus for me is using the connectors instead of having to use bullets. I hate bullets, .

[GadgeS3C]

Good practice to use relays to reduce the current carried by the switches wherever possible - also helps the switches last longer.

Alternatively you can double up the connections in the connectors - use 2 cables for the feed to allow double the current - do you need more than 40A?

Don't mind bullets in the right places but they are a nightmare when they're inaccessible.

[Cerberus90]

Don't know for sure if I need more than 40A.

It's got to feed everything that could be on with the ignition.

So :
Headlights - Main 10A
Sidelights
Wipers
Heater
Cooling fans (although as these are relay'd they could be perm live feed with the low side on ign, if I've got room on the fusebox)
One side of Indicators
Maybe a CD player at some point.


I'd imagine that could be getting close to 40A.
It'd reduce some thick cables that I've got to route too.


Got bullets on some connections behind the dash, but it will have a multiplug for all the wires that are leaving the dash so it can be quickly disconnected if the need arises without having to swear at multiple bullets.

Edited by Cerberus90 on Thursday 22 August 18:55

[GadgeS3C]

Relay the headlights and you should be well under.

Our 3000M doesn't have the lights wired through the ignition switch - must take a look at wiring diagram and see if that is standard. Better to have them wired to ignition but side lights should be separate.

With separate relays you don't need one big one.

[New POD]

Years ago I worked for Lucas Automotive Electrical, and when I fitted 100 watt spots to my citroen ax diesel (like you do if you live in the countryside) I used one relay per Spotlight. (Plus 4 fuses) Found them all in a cupboard in the development engineering dept.

[madsvlund]

Best solution is to add a relaybox with 6 relays and drive them with the ignition key and switches. I've used a relay and fuse box from a ford mondeo, but prepare for some hours doing the cable work.



The solution in between... put a normal 30A car relay on the starter solenoid, + a relay for the headlights and you will be fine. The kit car shops have some neat solutions you can mount in the engine bay with the cableing on the backside.
http://www.ebay.co.uk/itm/4-WAY-RELAY-HOLDER-BOX-S...

[Cerberus90]

GadgeS3C said:

Relay the headlights and you should be well under.

Our 3000M doesn't have the lights wired through the ignition switch - must take a look at wiring diagram and see if that is standard. Better to have them wired to ignition but side lights should be separate.

With separate relays you don't need one big one.

So make the large feed to the relay permanent and just have the low side on ign? Makes sense. No wait, Dad suggested that and it won't work. Because the sides are on permanent, the light switch is powered permanently, so when you flick it to headlights, they'll come on.

This is how I've designed it so far. Think I need to look at putting some line fuses in to seperate left and right sidelights.




The M series wiring diagram I've got shows the lights as wired up permanently.

Not putting a relay on the starter as the solenoid is a relay, the ignition switch feed to out starter (high torque) is just a standard 6.3mm spade.

Already got the fuseboxes (1 x 10 way, 2x 4ways) bought along with the relay holders and relays and flasher units. Just need to decide how I'm going to finally put it all togethor.

Edited by Cerberus90 on Thursday 22 August 22:08

[griff 200]

Kit car solutions do a fuse and relay board expensive but makes a very easy and neat job with good fuses etc . I fitted the plugs you quoted behind the dash so you can simply un plug and remove the dash . My advise keep it simple!!! Good luck richard (and use a soldering iron and heat shrink!)

[madsvlund]

An easy solution will be to add an Accessories, relay after the ignition switch, and let this relay feed the fusebox.

I did something else in my setup, inverting the ignition switch from positive to negative, all my relay's grounding is done throu the ignition switch.