Scooterotica

due to the disappointment of the DC conversion, i am planning a split AC/DC system...
I have used relays to switch the Pathfinders on.
I am planning on using AC for the standard lights and DC for the horn & Pathfinders.
Can I use AC to trip the relays, so from the switch to terminal 86.
But then have DC to power the lamps ? coming in on 30, and to the lamp from 87 ?

Byron,
The relay is activated by a current passing through the coil, activating an electric magnet, and making the switch.

When AC was applied to the coil, you would be switching this coil on and off at the same rate as the frequency of the AC voltage. Not ideal for your application, and I doubt that the relay would last too long

A solution of course is to stick a small rectifier on your AC signal to the coil, essentially converting it to a DC signal.... and away you go

Make sure that you use a smoothed full wave rectifier, or you may have exactly the same problem. Doesn't need to have a big current rating, as you are only driving a relay. You should be able to find a bridge rectifier in Maplin for pence.

Bob

ForemanBob wrote:When AC was applied to the coil, you would be switching this coil on and off at the same rate as the frequency of the AC voltage. Not ideal for your application, and I doubt that the relay would last too long

of course it would be, I should've thought of that I've been thinking about lambretta wiring too much lately.... I'll have another rethink...

Or buy DC relays.

Daggs wrote:Or buy DC relays.

they are DC relays, that's my problem, can you get 12v AC relays ??

Yes you can get 12v AC relays, but the problem is they will not be made for automotive purposes and you will need to be creative in positioning and mounting them. The ones we use at work are about 15mm wide, 100m high and 60mm deep and mount on DIN rail. Would fit in your glove box if you had room.

wow. sounds a bit unweildy. I made a little holder for the relays and tucked them behind the [series II] horn casing, so would like to use them.
I have been looking at the series II handlebar switch again and should be able to rewire this again to provide the necessary DC power to switch the relays. and I think I can make it so one or the other or both can come on... which is nice

Hi Byron, I'm a bit confused about the problem you are having with the DC conversion, mine's working fine BGM with the earth wire from the lighting coil connected to a new wire and then use the Ebay DC rctifier/regulator and a 7.2Ah battery. ALL lights running off DC + twin horns and 55 watt spot and a 35 watt fog. Switching on the aux lights does not cause dimming but would after the battery runs down which I would reckon to be an hour at least (constant use). In reality, you don't need the spots on all the time, although I guess in theory, a long cross country B road trip could cause problems eventually.

As for relays, as suggested, using a diode is fine and I had that on my previous set up when I was operating the DC horns and spot from the battery but using a rectified feed from the relevanty swithch to oprerate the relays which were both bolted to the to horn bracket behind my horn grill. That arrangement worked ok except at very low revs (up to about 1500 or so RPM) as there wasn't enough voltage present to operate the relay even using a full wave rectifier