Does your main beam tell tale get real hot ? have I done something wrong ? Ive just put a feed from the main beam relay to it, are....think Ive just worked it out, I should put it in the feed that operates the main beam relay I bet.

Anyone ?

James

This is what Id do!

Geoff
Rescued attachment circuit.JPG

goeff you've got deck on both sides of the lamp there. . . . . shurely shome mishtake..
Bob

Yep, thats what I think I should have done.

No mistake Bob,

What if the bulb blows?

Geoff

I'm curious - I presume that this is a 12v tell-tale lamp? If so, it really doesn't matter where you connect it in relation to the relay - I'd put it in the same circuit as the headlamp high-beam.

If it's a conventional lamp then it has a filament bulb inside. This will certainly get warm over time as most of the power used by a bulb is wasted as heat. I'd expect it to get warm to the touch.

If it's getting too hot, then either:
- You're touching the bulb
- The bulb is too high a wattage
- It's getting too much voltage (either your car's voltage is too high, or you've got a 6v bulb!)

If it really bothers you, buy a 12V LED indicator - they're tidy, fairly cheap and run almost stone-cold.

rgds,
David

I think that the schematic is wrong. You just shortcircuit the 12 V to ground, so your lamp won't burn!

So you've got a bulb that lights up when both its terminals are connected together!
Brilliant - you're gonna make a fortune!!!
LOL
Bob

If you remove the middle of the three grounds (the one that's short circuiting the bulb!) it MAY work. This would put the lamp and relay coil in series, giving reduced voltage across both - hopefully with enough voltage across the relay coil to operate.......

Sure aint gonna work the way it's shown there though.......

quote:

---

Originally posted by Bob C
So you've got a bulb that lights up when both its terminals are connected together!
Brilliant - you're gonna make a fortune!!!
LOL
Bob

---

forget that sheme..an bit..

wire it from the same + lead as the high beam..

the day the relais is bad..

you can see it on you high beam tell tale light..!

untherstand?? sow you directly if the bulbs gets power or not...

Tks

That wont work Geoff as Bob says youve got 2 grounds one through the bulb one to ground,juice passes thru the path of least resistance so it wont light yer lamp.
As David says either your wattage is to high or your touching the lamp even the smallest filament lamp gets hot errrr other wise you get no light.
Just wire your bulb between the headlamp feed off the relay and earth.
Cheers,
Bob

Hello!

Note to self - must have tea in the morning before engaging brain...the thinking behind my circuit was to put the relay and tell-tale in parallel thus some current would flow through the bulb. However - i showed the join at the wrong place - my appologies!

Heres the correct version.

Thinking about this a bit more carefully...since I(current) is equal to the Voltage divided by the Resistance, the bulb will only draw as much current as is dicatated by its resistance so the temperature (roughly proportional to the resistance I guess) should be the same wherever it is put assuming it has 12v one side and earth the other.

ah I love the smell of wire insulation in the morning!



Geoff

[Edited on 23/6/05 by jambojeef]

[Edited on 23/6/05 by jambojeef]

That would work Geoff but it wouldnt make an iotas difference to the heat given out by the bulb,all it would tell you is your main beam switch works.
If you put it on your relay output it would tell you your main beam switch works your relay works and the feed through the relay is OK.
Cheers,
Bob

Doesn't matter where it goes - if its got 12v across it its got 12v across it, resistance of bulb is constant so current must be so therefore the power disippated must be!

V=IR
Power = VI

so Power = V*V/R

Good point Bob!

geoff

I agree with all those whom say "it doesn't matter" if it lights when your mainbeam is on... sorted. If it's getting too hot (?) a typical bulb glass surface temp should hit 600C halogen is 860C IIRC - course it will burn your bloody fingers!

Personally it seems to be typical behaviour. If you're not happy go LED as stated.

Thankyou, FFS yes I know I filament gets hot :rolleyes: and therefore the glass etc, the bulb is in a casing for it to slot into the dash but the casing gets suspiciously hot to the touch. Now obviously, before anyone says, its in very close proximity to the bulb so before anyone starts to tell me about the conduction and convection of heat etc etc does anyone elses tell tale light get very hot to the touch ? ? I guess from the responses everyones does and you live with it or you are using LED's ? I dont want the vinyl near to the tell tales on the dash to start to melt when Ive got the lights on or be constantly aware that it may start to melt whilst Im driving along with them on, I think I may use LED's if nobody can offer any other advice.

James

James

If you are really concerned at the heat generated you could fit a resistor in series with the lamp to reduce the current.

This will have the effect of reducing the heat generated, but also will reduce the brightness of the lamp.

Would not be a problem at night me thinks, but might not show in daylight too clearly. (then again, who cares during daylight!!)

Cheers

Mike

Or get the lowest wattage bulb that fits...

DJ

I don't see any mention of what wattage the bulb is. Get a LED replacement or a smaller wattage bulb.
Cheers John