I'm rewiring the 101 and i'm trying to plan my wiring loom before i start rather than doing it all ad-hoc. I'm hoping that this way i can order enough bits of differently coloured wire such that i can tell what is what later - and not over order too much and spend all my cash!.
Can anybody recommend some software that is free (or very cheap) that i can use to plan my wiring.
I'd basically like it to keep all my lines tidy and sort out the labelling.
I've been googling but i cant seem to find anything good.
The best ive got is a bit of GPL software called 'Dia', which works - but it is really hard to get all the wires tidy and labelled and i seem to be spending ages just reaaranging things to get new bits in.
), free but cut down - on special offer this month, only 600 quid for the pucker version - bastards charged me 850 the month before, it has full 3D sketching capability. I have a CAD model of a 101 ambi in my system at work, but I haven't used it for this kind of thing. Each wire can be a part for a "Bill of materials" list which you can export/import into Excel or OpenOffice.
IME (with other classics, not Land Rovers), they're one of the most genuinely helpful and knowledgeable suppliers you could wish to deal with. They will customise looms exactly as you require, and make a much neater job than you can easily achieve yourself.
They're only a few minutes from M1 J25, so worth calling in to see them, especially to top up with odd connectors and so on.
I've looked at their looms for series vehicles before, and their loom will work out more expensive than making my own. I want so many customisations that i might as well do my own in a way!. I'm fitting fuse boxes and relays where they wernt before and building in a lot more stuff than is stock.
Put in some over-capacity on the permanent live and switched live loom. Once you get into the "I'll add this and that" scenario it's easy to run out of live terminals to feed everything from and you'll end up having to splice into feeds that you've already neatly fitted. I know! Some sort of live bus-bar for both permanent and switched might never get used, but as sure as sh*t stinks you'll discover that you need another live when you haven't got one easily accessible.
Putting on my ex-Wiremans hat..... and ex-Rists hat too...
Vehicle harnesses are not simple things, as designed for vehicles, even for basic harnesses like Series/101's etc. There's splices and centre-taps all over the place, and it's not just a case of "ah! there's 12V there so I'll tap into it", a lot of thought and sums go into dealing with failure modes, current ratings and not starting fires etc. In fact vehicle harnesses are unique in allowing more that 2 cables on a terminal and that sort of thing
- if you did that on control cabinet you'd be shot, possibly after being sacked....
I'd start with a schematic of your vehicle on paper, and start "at the corners", working back, via the dash, to the battery/ alternator. As you progress you can add up currents etc to decide on which size cable to use, or if another seperate feed/earth is required. Ideally you need to allow for water etc causing short term shorts and crossovers between circuits, but that's probably over the top for what you are wanting to do. There are some legal things that you might like to take into account, such as a single failure should not cause all the lights to go out (diagonal opposite corners should remain illuminated) etc
When you get back to the dash, you can work out which switches can be fed from where, and after a few interations you should end up with (notionaly) one lead to the battery/alternator.
Getting the cable lengths right is never easy, not least as you have to remember to leave slack to allow for vibration, re-fitting of units (bulbs etc) and avoiding chaffing and heat. Until you've built the first one! Again though, starting "at the corners" and working back to the dash, building the harness (cables in and out and all about) as you go with "definately over length" cables will avoid embarassing moments. OK, so you will waste quite a lot of cable by the time you get to the dash as it's a one-off, but then when you buy more than a few metres it's often cheaper (or more cost effective, anyway) to buy a reel. Idealy, each cable sould be a different colour/tracer combination, but that's not practical even on a small harness, so the un-attached ends should be marked with labels (a pain in the bum) or idents which indicate where they came *from* (not too).
Use proper terminal crimps, fited with a proper crimping tool (widely available these days for not much money) - *never* use Scotch Locks...and don't solder anything. A proper cable stripper will save a lot of grief later. Avoid using ty-wraps to hold you new harness together - use sprial-wrap or split convolute tube if at all possible and/or harness tape.
It sounds like a load of grief, but if you plan it well it's not that bad a job, but pretty time-consuming. The harness is the first part fitted to a body in the factory, obvioulsy much easier to do, but retro fitting isn't that bad [1].
Richard
1[1] excludes Bentley's, Range Rovers and the like - it takes two people just to lift some of the harnesses fitted to the likes of those vehicles.
While the idea of a big power bus with each item dropped from it locally feels good in a nice protected environment on a vehicle I'd worry about position on relays. Keeping them up and out of the damp could end up making the loom more complicated that wiring each item back to the central switch gear.
Also keeping the load well distributed across a lot of fuses means that you minimise the disruption caused by any one fault.
eg: Having the reversing light fuse and the reversing light relay down by the reversing lights might make for a neat, modular system but on that night, when the sleet is coming past horizontally and I didn't see the damn pile of bricks, I'm going to regret it.
I didnt know about the diagonally opposite thing - my landies have not been rewired like that and im not sure who would check it? (i do have every complete set of lights in the landy on a different fuse)
I was going to buy some reels of cable - VWP sell small reels so i was thinking of lots of short reels in am many different colours as i needed (hence my planning.) A proper crimping tool and stripper was on my list too.
Am i better off using preinsulated crimp terminals or the uninsulated ones that have a seperate sleeve, and a different crimper (as already used on my loom).
I was straying towards the latter.
I was also planning on making a lot of bits modular - such as my dashboard.VWP sell multi-connectors that use crimps, so if i could run everything on my dash through a few of them it would be good. I've had no speedo for ages in the 101 and I couldnt actually remove the dash properly without cutting the odd bit of wiring loom (and chiselling off the screws which were put in before the windscreen!)
The only thing i cant find for sale is like steve suggests a +ve 'bus-bar" or any sort of simple thing i can use to connect multiple feeds. VWP also sell cheap fuse boxes that have either multiple blade terminals coming off each fuse or linked fuses (so you can have a block for ign live and ablock for perm live) which is annoying.
In my landy i have got various earth points which are a nut through things that i have connected to via ring terminals. I could do with a few insulated ones of these for positve supplies.
Perfectly - just not viable on volume production, in fact it's a sort of electromachanical version of a CAN bus! If you got really carried away you could have a lamp indicating the stauts of every circuit by monitoring the relay's state....... now that would be fun!
I retrieved a busbar from a skip recently, solid copper 25mm by 6mm with brass nuts and bolts, I've just had a search for it an can't find it amongst all the other junk I've saved. If I find it you're welcome to it but I suggest any industrial electrician will have them.
If you look at
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and the busbar in the top right of the biggest image that's what I am talking about, a bit heavy duty for 12V.
When I rewired my SIIa I decided to make my own loom so i could wire it how i wanted it, with the extras. As for diagrams I laid down the circuit diagram using Microsoft Visio. The loom layout and wire listings i did the old fashioned way - using pencil and paper.
On or around Tue, 16 May 2006 10:58:21 +0100, beamendsltd enlightened us thusly:
modern ones (well, actually, modern ones use CANbus and suchlike, don't they?) but fairly modern ones have separate fuses and circuits for L and R sidelights and rearlights, plus separate fuses for each di and each main. mind you, the whole f**kin' lot goes through the lighting switch, do it only needs that to burn out and hey presto, no lights at all. by rights, you should have 2 separate circuits and 2 separate switches to the sidelights and headlights, but they almost all don't. I bet they would on an aeroplane... must be some reason for aeroplanes having about 57 switches on a bloody great panel above the pilot's head.
excellent post BTW. I've often contemplated rebuilding looms on old, knackered stuff and always chickened out.
The other thing you didn't mention is that to get it "right" you need to look up the list of what colour wire does what, and buy wires of all manner of pretty colours...
either that or do it like the aircraft and have all the wires the same colour identified by those little numbers and letters... but the pretty colours route is good 'cos then you can take the colour scheme from the wiring diagram and replicate it.
I can rememeber a few of 'em: lighting supply is white/blue, main beam is blue/white, dip beam blue/red for example. however, on the newer stuff, the blue/red only goes as far as the fusebox then it splits into 2 colours for LH and RH dip.
and I've no doubt there are several systems, all different, too - I think the japanese ones are all different colours, for example, and they use different connectors, too.
vehicle wiring products is the place to go for crimps and crimp tools and so forth.
On or around Tue, 16 May 2006 11:39:17 +0100, Tom Woods enlightened us thusly:
If you go back to the series II, you'll find it had 2 fuses. series IIIs started off with 4 fuses, and a modern (pre bus-type) RR or disco has about
the requirements have got more complicated as well as more stuff being added that needs fuses, the only good thing is that it's not all retrospective...
Well, if you have the electrical symbols stencils you've got a head start, although i still had to make some custom symbols. It does have the advantage that once you've connected everything up you can move things around and the wires move with it. I suppose you could use that feature to do a loom layout as well.
There is nothing so nice as a properly wired loom with everything labelled from end, and identified with non-removable lettered and numbered coloured rings (in resistor colour code), it just looks RIGHT.
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