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Amps Relays and things...
Willie - 3/4/03 at 12:04 PM

Hello,

Ok, I can weld wee bits of things together, beat/form sheet etc...but wiring - errrrrr.

After studying the wiring diagram in the book, it seems that it should work ok, except for the right side repeater being connected to the main beam or something.

Now the thing I'm wanting to know is, what Amps does main beam, dip, horn and teh fan require? If I'm for running each through a relay, I'd need a relay that says something like "12V 40amp" or whatever the amperage is...right? I'm afraid this is my first attempt at wiring anything...hopefully my last too.

Also, a 4 pin relay is a normal one that I could use a switch to activate? Why don't they just make big brute ignorant switches anymore?

Sorry for my ignorance, hope someone can help.

Thanks in advance,

Willie


stephen_gusterson - 3/4/03 at 01:20 PM

Hi

Im the opposite from you - im a hardware / software / electronics guy that has to struggle with mech engineering work!.


A good pointer is to get a haynes manual on your donor car. look at the fuse ratings they have in there.

Basically, every 12 watts of consumption at 12 v is one amp. (In reality a battery goes to about 13.5 volts in use).

So, a 55w main beam will be a tad over 4 1/2 amps.

A Horn is likely to be fused at 10 amps.


For relays, I suggest that you DONT buy them....use the ones from your donor or from a scrappy.


I just looked for info on connections, and found this site - looks to me that its gonna help you a lot


http://freespace.virgin.net/tommy.sandham/relays.htm


DONT use relays with different terminal numbering - they are not the same inside.

Good luck. If I can help further let me know!


atb

steve


David Jenkins - 3/4/03 at 01:20 PM

P = V x I
where P is power in watts, V is volts, I is amps.

Swap this around according to what you need to know, e.g. if you have a 60 watt bulb on 12 volts, it will take 5 amps. ( I = P/V)

This is good enough for most auto needs, e.g. selecting the best rating for the connecting cables, fuse sizes, etc.

DJ

P.S. Steve sneaked his reply in while I was composing my post!!!



[Edited on 3/4/03 by David Jenkins]


eddymcclements - 3/4/03 at 02:43 PM

Get Vehicle Wiring Products to send you a free catalogue. As well as all the parts you'll need, there's a lot of useful info about what pin-outs different types of relays use.

Cheers,

Eddy


Willie - 3/4/03 at 05:34 PM

Guys,

Thanks a million for the help, helps alot. I'll stick a few more photos up when I have the wiring done to let you see how your help was put to work. I've just spent a fair bit of money getting bits, so I'm not spending anymore buying looms...I'm wiring this thing.

I've got everything, except a hazard switch/unit. I take it you can use a hazard swtich and a flasher unit, or is there a difference between flasher and hazard units?

I've got the important bit...big red starter button

Thanks again.

Willie


stephen_gusterson - 3/4/03 at 10:45 PM

the flasher bit does both.

its the way the lamps are switched.

if you are using a ford sieera or granada column then the swithcings all done for you.

If not you have a bit more wiring to do......let me know if you need more help

atb

steve


David Jenkins - 4/4/03 at 07:41 AM

Just to be different, I use a flasher relay with a separate hazard switch!

It's an electronic flasher relay from Premier Wiring, which is rated for running all the flasher lights together.

I am using a Hella hazard switch, which has about 10 connections! Fortunately it comes with good, clear instructions...

DJ


stephen_gusterson - 4/4/03 at 09:04 AM

its the switch thats the important bit.

Most flasher units will support the use of four bulbs - ie do the hazard function. Its connecting the two sets of lights together AND stopping them from all flashing in normal use thats the bit the switch does. Plus hazards need power when the ignition is off.


I think my pics section has a drawing.

atb

steve


David Jenkins - 4/4/03 at 09:59 AM

4 bulbs?!

You mean 9 bulbs! (2 left + side repeater, 2 right + side repeater, 2 dash lights, and the one in the flasher switch itself)

If I remember correctly, the flasher relay is rated at 46W/92W (46W in regular use, 92W with hazards working)

The hazard switch is quite complex - it caught me out, in fact, with a real 'doh!' moment. Connected it all up, but it refused to work - spent quite a while fiddling with wires - until I realised that 'button in' was off, 'button out' was on. Worked fine when I worked that one out.



DJ

[Edited on 4/4/03 by David Jenkins]


paulbeyer - 4/4/03 at 10:01 AM

quote:

I've got the important bit...big red starter button



Where from, how much? I want one.


eddymcclements - 4/4/03 at 10:15 AM

Farnell - product code 109282
or
RS Components - product code 320-815

About 8 quid plus the VAT. Nice switch - definitely has that "I want one" factor.

Cheers,

Eddy


stephen_gusterson - 4/4/03 at 10:44 AM

quote:
Originally posted by David Jenkins
4 bulbs?!

You mean 9 bulbs! (2 left + side repeater, 2 right + side repeater, 2 dash lights, and the one in the flasher switch itself)

If I remember correctly, the flasher relay is rated at 46W/92W (46W in regular use, 92W with hazards working)

The hazard switch is quite complex - it caught me out, in fact, with a real 'doh!' moment. Connected it all up, but it refused to work - spent quite a while fiddling with wires - until I realised that 'button in' was off, 'button out' was on. Worked fine when I worked that one out.



DJ

[Edited on 4/4/03 by David Jenkins]



I will be a bit more specific for David




The four bulbs are a total of 84 watts.

(21w x 4)

The extra ones are :

2 side repeaters - (5 w I think?) = 10w

2 dash lamps (or 1 if you are like me - usually 1 w) = 2w

1 in the switch = another watt.


Thats 13w total for the extras - not even another bulb - and the flasher copes with that.

Its included in the mfr spec for a 2 or 4 bulb unit

Being really picky, I could say that the total wattage will depend on the engine rpm - and hence charge from alternator making the battery go from 12v to around 13.8v, and the drop due to the wiring which will cause about 15 w load variance anyway.

Buy I wouldnt,

Im not that kinda guy





atb

steve


btw

I dont think a start switch is that special - it just needs to carry the starter solenoid current - a few amps - and be wired from 12v to the starter solenoid terminal.

Any push to make switch of the right rating will do.




[Edited on 4/4/03 by stephen_gusterson]


David Jenkins - 4/4/03 at 11:18 AM

quote:


Buy I wouldnt,

Im not that kinda guy





Never stopped you before, Steve!

David


Willie - 4/4/03 at 11:38 PM

I got the starter button from Radio Spares, RS Catalouge. Ordered it off the 'net about 4pm on wednesday and it was on teh door step 8am the next morning...and that was the standard delivery specified. Usually you need to have an account, being a vat registered company, but order it over the net and it's ok. Part number is 320-815.

With the postage included it ended up about £15. Steep enough in my opnion, but an essential item for pose factor. After hacking at my dash etc I now have the starter button, indicator switch, horn button, lights switch, and several warning lights all in...definetly worth the pose factor.

Soon going to be starting the actual real wiring rather than mounting the bits.

Willie

p.s.An indicator switch is far more racey than a wimpish column stalk.