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RELAYS

Posted: Tue Sep 20, 2005 5:39 pm
by newmoggy
Im in the process of playing with my lights.

Im keeping my halagon headlamps which incorparate the sidelights.

The original flashing sidelights are now just indicators, this will make the car look original whilst being more practical.

Ive just fitted some of the old 57 - 62 rear lights which act as rear red & brake lights only. I was thinking of fitting extra round indicators.

However ive started to wonder if I could fit a relay in the boot to allow the brakelights to act as indicators as they would have done when new without having the whole system wired through the relay.

Rather than fit the DB10 relay at £50quid & have to rewire the lot, i wondered if anyone knows of a simple relay that I could get to act on the brake light & rear indicator circuits in the rear.

I.e the relay would fit between the live cables in the boot that would go to the brake lights & the indicators & the cable that would then come out & join at the light units to power the bulb?!

Any ideas?

Posted: Wed Sep 21, 2005 4:14 pm
by woo
What I think you appear to be saying is that you want the DB10 function of flashing the brake lights without using the DB10 itself. The rear bulb is a 12 volt 5/21 unit. The 5 watt filament has its own supply for the rear light and the 21 watt filament has effectively two power supplies. (1) A constant light supply via the brake light switch and (2) A flashing supply via the indicator unit. Either of these supplies can be used independently of each other, but when both are used together the flasher supply overrides the rear brake light supply. So presumably you would want something attached to the brake light supply that would be able to sense whether the indicator supply was active or not, and if sensing that the indicator supply was active, would be able to cease the normal supply to the brake light. I'm sure it could be done. The DB10 does this via relays, presumably a circuit could be built that would provide the same function with modern components. Perhaps some of the Electronic Whizz Kids on this site could help.

Posted: Fri Sep 23, 2005 12:39 am
by newmoggy
exactly what I want!! Anyone got any ideas???

Posted: Thu Sep 28, 2006 9:50 pm
by jtd.75
and me has anyone solved this problem yet

Posted: Thu Sep 28, 2006 10:15 pm
by alex_holden
The manual shows the circuit diagram of the DB10, and it looks trivial to replicate with a pair of 12V DPDT relays. I can draw a diagram if you like?

Posted: Thu Sep 28, 2006 10:39 pm
by jtd.75
Hi Alex I have sent you a pm. saying yes please so if you send the dgm to my email address
Jimmy

Posted: Thu Sep 28, 2006 10:54 pm
by jtd.75
Alex when you do the diagram for me would list the parts that I would require and where I can buy them, it would have to be by mail order as Anglesey. a bit on the scarce side for things that.
Regards
Jimmy

Posted: Thu Sep 28, 2006 11:35 pm
by alex_holden
OK, here's a quick and not very neat sketch. The only new parts you need are the two DPDT relays. I can have a look in the catalogues for you in the morning, or I might have something suitable in my parts collection (but probably PCB-mount rather than spade connectors).

Image

The turn switch energises the left hand relay when you are turning left and vice versa. It only energises one relay at a time - never both. When the relays are turned off the front indicator lights are disconnected and the back stop/indicator lights are connected to the brake light switch. When a relay is turned on it connects the front and back lights on that side together and supplies them with power via the flasher unit.

Note that the sidelights and tail lights are on a separate circuit - the ones that are a single lamp use two filaments in one bulb.

Apologies if I've made any silly mistakes in this post - it's getting late and I haven't built and tested the circuit.

Posted: Fri Sep 29, 2006 9:47 am
by alex_holden
I've just had a look at Maplin and it seems they don't do DPDT automotive relays, so I've redesigned it to use two SPDTs and two SPNOs:
Image
I know, it would have looked neater if I'd done it in CAD, but it was quicker to sketch it out on paper and scan it in. I didn't receive your PM BTW.

Posted: Fri Sep 29, 2006 2:03 pm
by jtd.75
Hi Alex how about this then.
Jimmy

Posted: Fri Sep 29, 2006 3:38 pm
by jtd.75
Thanks Alex for all your help in the matter both for myself and I am sure many others.
Jimmy

Posted: Tue Oct 03, 2006 11:31 pm
by IslipMinor
Jimmy,

I have a diagram that I used many years ago on a Willys Jeep to do the same thing. I updated it a couple of years ago and it uses 4 standard automotive relays - 2 4-pin NO, and 2 5-pin DT as Alex shows. The diagram shows all the terminal number connections and is a simple point to point wiring job.

If you send me a PM, I will email you the document (Word).

Posted: Fri Oct 06, 2006 3:07 pm
by bmcecosse
This will not be legal for your age of car.

Posted: Fri Oct 06, 2006 3:21 pm
by alex_holden
I don't think Jimmy says anywhere in this thread how old his car is. Searching back through previous posts he mentions owning a 1960 saloon, which is older than my 1963 Traveller with a factory-fitted DB10.

legal

Posted: Sat Oct 07, 2006 2:58 pm
by jtd.75
Hi folks BMC, Alex, Richard. The car in question is a 1960 2 door saloon ( 948cc first reg 06-06-60 and he bought it for £300 17s 06d) and came fitted with trafficators so I am told and its original owner the Rev Rowlands from Pentraeth (Anglesey) had these removed and flashers fitted when he gave the car to his son when he went to Liverpool Univ so I am told. There are blanking plates fitted to were the arms were. I asked at my local garage that does the MOT's for me before I started to ask on this forum about relays, and his remarks were as far as he would be concerned he could not see any legal reasons as to why I could not use my rear brakes lights as flashers as well. It would seem that when he logs into the computer to do mot's it would appear to be what ever he says is original for that year of car to within reason. I know when I took my( April which had a DB10 relay fitted once upon a time before a altanator and flashers fitted by my friends daughters father when she when to Edinburgh Univ. ) 1963 Morris in last week he queried my seat belts and asked did it have any fitted from new and I replied there was none on when I got it and that I fitted the second hand ones on it now, so he said none fitted!!. To the best of my knowledge the car has not yet failed an MOT, and I am the fifth owner and the last three being friends of my wifes. I hope you legal beavers out there can shed some light on my reply.. I hope I have not wandered to far from the original qestion. :wink:
Jimmy

Posted: Sat Oct 07, 2006 4:43 pm
by rayofleamington
Flashing brake lights is legal if that is how the car was made...
Minors were made like this 61 to 63 (mainly in 62) before the orange flashers were added. As you have trafficator holes, then that proves it wasn't a flashing brake light model (although not an easy assumption to the untrained eye)

Therefore 1960 car should have either the original trafficators or it can be updated to flashing orange indicators. As far as I can tell, updating it to a later minor spec is bending the rules a bit. However this is certainly far safer than converting to the original trafficators.

If at any point you do fit the trafficators back on, it is possible to have both systems working independantly.

flashing brake lights

Posted: Sat Oct 07, 2006 7:47 pm
by jtd.75
Thanks Ray, How ever my son came up with the remark today saying would anyone behind me in the car know that a flashing brake meant that I was making a turn either left or right because he would not if he did not know what I had converted the brake lights to act as indicators as well and he said that he did not think that any modern day driver under a certain age would either. He would think that I had a problem with the lights, so with that in mind I think that I will not bother with the brake lights and fit amber flashers. Which now means that I have four relays.
Thanks again all for your imput on this matter.
Jimmy

Posted: Wed Oct 11, 2006 5:11 pm
by IslipMinor
Jimmy,

I think that's probably the right way to go.

When I restored our 1958 Minor in the late '90s I debated what to fit. I had fitted some 'plant on' aftermarket flashers when my mother bought the car secondhand in 1965, but they had to go and I very seriously considered going the DB10 'equivalent' route as well, to retain the original 'look'.

In the end recognised that many drivers might not realise what was going on, so at the last moment fitted the '64 on later style lights front and rear. And, yes, the indicators do still work, but can be switched off when on dual carriageways and motorways (don't think they are designed for high speed operation!)

Posted: Sun Oct 22, 2006 4:26 pm
by boggymoggy
IslipMinor, Hi, any chance of a copy of your wiring diagram of your jeeps indicators as i am also trying to wire some up and it sounds as if your diagram is quite easy to follow.thanks

Posted: Mon Oct 23, 2006 12:22 am
by Axolotl
would anyone behind me in the car know that a flashing brake meant that I was making a turn either left or right
Probably not, but judging by most drivers I see nowadays, no-one knows what indicators are for anyway. :evil: