Wiring tidying

[dougbgt6]

Head lights on relays means BRIGHTER headlights and minimal load on the light switch. And in response to "A TR7 16V" this kit cost £10 and contains relays, connectors and fuse. How much does his solution cost?

Doug

[A TR7 16V]

2 minutes ago, Iain T said:

Back from a cake break 🍰

Erm, and apart from the obvious word description what is the point of this widget? 

At school I used to run in the relay, those black boxes don't look the same...   

 

My reason is that switching the current to feed the mains is doing the fourtyoddyearold toggle switch up the column no good at all. Whereas, one of these relays does the switching remotely, so the load on the switch in the column is small, possibly just milliamps.

A kit as shown can also take the load off wiring loom, which matters if you want bigger better lights (like what I don't) - the existing wire's a bit thin for very many amps, will heat up because of its resistance, and lose power that should, otherwise, be shining out the front.

Graham

[Iain T]

Thanks Doug, just googled and they are basically an electromagnet on/off switch? 

Graham, so the in my simple terms the low load side is used to activate a higher load application? 

Iain 

[Anglefire]

13 minutes ago, dougbgt6 said:

Head lights on relays means BRIGHTER headlights and minimal load on the light switch. And in response to "A TR7 16V" this kit cost £10 and contains relays, connectors and fuse. How much does his solution cost?

Doug

Must admit, I have gone for a bespoke option - basically two relays and suitable wiring of the correct colours and connectors etc. Went for relays with twin make and break contacts (two terminal 87's) for neater wiring to each headlamp. 

Just got to get around to fitting them! Like the fuse box that has been in stock for 2 years  

[A TR7 16V]

2 minutes ago, dougbgt6 said:

Head lights on relays means BRIGHTER headlights and minimal load on the light switch. And in response to "A TR7 16V" this kit cost £10 and contains relays, connectors and fuse. How much does his solution cost?

Doug

Relays on there own won't do much to make the lights brighter, it's using thicker cable to power the lights and shortening the run lengths that makes the difference. Perhaps as much as 10 percent with 2 x 55 Watt lamps going from 15 foot of 18awg (about 1 volt drop) to 8 foot of 12awg (about 0.13 V drop) . The other big advantage is that you can fit and feed much higher wattage lights, which I wouldn't trust the current (lol) cable to do.

But I don't want brighter lights. On the Sprint, I wanted to stop replacing the flasher switch every 5 minutes, cos its a bitch of a job. 

As to how much does it cost to just insert two relays in the existing feeds: If you have to buy it all, the 12awg wire's like a quid a meter; UI spades are like 10 or 12p each in 10/20s; and 40 Amp relays are a couple each. 

The big cost is probably in the ratchet crimp tool. But I'd argue that's a very worthwhile expense if you're gonna take on much electrical work on the car.

I already have that, and the lucars, relays, and wire, in the box o' bits. So I'd save the whole tenner.

But even if you may not save much money using a kit, where's the challenge and the buzz in doing it right?

Also I think it's a thing best hidden away neatly under the dash. But I know that's personal preference.

Graham

[A TR7 16V]

53 minutes ago, Iain T said:

Graham, so the in my simple terms the low load side is used to activate a higher load application? 

Iain 

Exactly. There a low excitation current through the coil in the electro magnet of a few hundred milliamps max (50 to 100 Ohms at 12 to 14V). And that switches nearly as much load current as you like - 40 Amp relays are cheap enough and could supply power to over 400 Watts of lighting. I'd want a bigger safety margin than that on a road car, but 200 Watts should be fine. Mind you, you'd want some fat cables for that 40 Amps.

Graham

[A TR7 16V]

BTW, in reducing the loss or feeding higher power lamps it makes no difference if the relays are by the battery or by the headlights. It's the resistance between the battery and the bulb that matters, not which side of that you put the switch.

Graham

[Peter Truman]

Remember I'm 10hrs ahead of you so I'm still catching up on the fuse box discussion, I like those blade fused LED indicated fusebox's and might convert my Vitesse to a 10 bladed unit combining the original and my extra accessory 6 blade Hella unit, which has the electric fuel pump, emission solenoid valve (to stop run-on), security system (insurance requirement), electric windscreen washer pump, emergency 4 way flasher battery power, and airhorns (relayed), 3 ignition and 3 battery fused supplies.

Ref the front of bonnet headlight wiring I retained the original system, but replaced with new all the female single and double bullet connectors cleaned the crimped male push ins with a dremmel small rotating wire brush lubed them and the female bullets with di-electric grease, and tidied the wiring up with coloured plastic sheathing to each side of the bonnet, headlights and dipped wiring in red sleeving and the flashers and side lights in blue sleeving.

[DVD3500]

8 hours ago, Peter Truman said:

Remember I'm 10hrs ahead of you

Which is why I never worry about tomorrow coming to pass... as it already has in Oz!

 

[dougbgt6]

11 hours ago, A TR7 16V said:

Relays on there own won't do much to make the lights brighter,

Yes and no, it’s taking the load off the switch that brightens the lights. Over the years the switch innards tarnish and become resistive, you get a voltage drop and dimmer lights. More worryingly the switch gets hot.

Doug

[Pete Lewis]

volt drop is common on my vit6 we measured something like 10.5 volts at the headlamps  

relays  upped that to  12/14v   it turns old filament glow worms  into HEADLights  change the seal beam for halogens and you up the lighting to very illuminating 

i also ran a direct earth replacement from the lamp units the the battery earth bolt .

and we earth bonded all the body and chassis together , to eliminate rusty earths  of front to rear  

Pete

 

[Badwolf]

When I originally read the posts about these cheap oriental relays for the headlights, I thought oh yeah, another gadget I don't need. But, out of interest turned on the headlights and was quite shocked at how warm the switch got. Obviously when driving, you switch them on and then off when you stop with a single push. If wearing gloves you wouldn't notice anyway. After installing, no heat to the switch and yes, brighter lights. I would never have thought it. Money well spent in my view. Not original, but safer and an easy reversal if you want to go back to the original layout for some reason. What's not to like, as they say these days.

[johny]

yes Ive just taken my 3 position main light switch apart because a spring has failed inside and found the contacts are pretty burnt. This damage plus the broken mechanism means Ive had to convert it into a two position switch so the contact that was used just for the instrument lights now does everything. No big loss but to prevent further damage, especially as theres now even more load on the one set of contacts, I need relays...

[Iain T]

Loving this, I really do feel my electrics need sorting and relays do seem a good idea. I like learning and want the know more! 

Iain 

[A TR7 16V]

I don't think it's a difficult mod whatever you choose to do.

The main issue you have to decide on is whether you want the car to look largely the same and just want to get rid of the problems with the load on the switch, or whether you want even more of the lights, like make the very most of the 55 Watt bulbs possible, or go to higher wattage bulbs. Both making the best of the 55s and fitting higher wattage bulbs needs upgraded wires from the relays to the bulb connectors and the earths from the bulbs to the chassis (I've a memory that the earths are a bit thin already).

The former mod, largely hidden under the dash, is what I intend to fit. I can certainly photo-document that as I go, if there's any interest. I guess I can look at putting the relays as near the battery as possible, so that the losses in the runs down to the lights can be minimized either with the existing wires or additional, higher capacity wires. The limit is probably that I don't want to open the loom up. I'm not totally averse to cutting the wires if I must, but I would like to find somewhere I can insert the relays at bullet connectors. I'm guessing that means putting the relays more on the driver's side, which adds a few feet to the run from the supply to the relays and from them to the lights. So I know I need to go look at the options.

Graham

 

[Badwolf]

Graham - There is always interest on this forum and anything you post will help someone. When Aidan posted his project for the fuse box I didn't follow his instructions to the letter but amended them to suit my needs and ideas, however without his original thread I would never have even attempted it. I think that goes for many of us. Colin suggested fibreglassing his gearbox tunnel cover...on my to do list. Old dogs, new tricks??? Definitely.

[DVD3500]

Woof!🐕

[A TR7 16V]

I had a look under the dash and such. For me, the obvious place to insert the connections to the new relays is into the bullet connectors at the bottom ends of the column switch wiring. I know that won't suit all, but it does what I want.

So, Here's the wiring diagram as it should be when the relays are installed (though not all the connections to the Radio/USB player are in). The issues are that both relays have wires of the same colour going to different pins. It also needs the dual bullet connector on the brown and red feed from the master light switch swapping for a triple. It should (other than where I've put fuse 11, which is not relevant) follow the convention of showing where the bullet connectors are as near as possible.

I will be soldering the bullets on the wires to the relays, because I don't have a crimp tool that does them - if anyone has a cost effective solution to crimping them I'm interested - and that's all doable out of the car. 

There's no mods needed to the car wiring, other than breaking the connectors and replacing the aforementioned dual for a triple one, and finding an earth for the relay coils.

Graham

[A TR7 16V]

Needs revising for the flash I think. It wants the relays supplied off the other side of the light switch, from the brown and blue wire off the fuse box.

Graham

[dougbgt6]

The Chinese kit tucks neatly into the bumper using the existing retaining clips and is not visible until you crane your neck. All that is required is a feed from the battery which I took off my new fuse box. 

Doug

[Iain T]

Graham is this diagram for a GT6? Just taken a closer look and it's just the headlamp relays? 

This is why I want to make my electrics more robust and reliable. Being historically correct isn't as important as working properly. The take off from the loom is the engine side of the bulkhead. 

 

[A TR7 16V]

No its not GT6, it's a Herald 13/60 circuit diagram. 

The attached corrects the error for the operation of the relays off the flash switch - I realize why I made that in basing this mod on the one in the Sprint, because that has the master light switch in the column housing as well, so the feed up there is permanently live. It does now also take the load of the master switch, which could be an advantage.

So I need to look closely at the connectors for the feed into the back of the master light switch. But I'm assuming I'll be able to split off there with a piggyback Lucar, putting the female of the new lead on the switch spade and putting the female feed onto the male spade on the piggyback Lucar. I think the piggies I have will take a fat enough wire to feed the lights, i.e. the same weight as the output from the master switch. If not, I may have to lash out on some fatter ones.

Graham

[A TR7 16V]

I've looked at the master light switch, and there's a spare terminal that's permanently live, i.e. in parallel with the brown/blue feed. So that solves the problem of where to run the lights off. I also found a source of 2m of brown/blue, 3mm2 wire for £1.20 inc p&p, which seems remarkable. And I've found the 2.5mm2 blue and white and blue and red wire. But I've only 1 x 40 Amp relay in the box o bits (could have sworn there were 2). So there will be a small delay while I get another.

Graham

 

[Anglefire]

I prefer to use thin wall in my cars. Carries more current for a given size. 

[Peter Truman]

Iain what's your main 4 fuse box make/from looks like a good upgrade from the original 2 glass fuse Lucas box, also is it a glass or blade fuse set up.

Does it have any ref numbers on it

Regards

Peter T