Charge indicator (ignition) light

Howard

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My memory ain't what it used to be, and I keep leaving the ignition on - not wise with coil ignition.

Can anyone tell me how to fit an ignition warning lamp (one that goes out when the dynamo's charging)?

I'm using a Lucas dynamo with a solid state regulator.

I've had a thought (dangerous), that if LEDs only work when connected the right way round, can I just connect one accross the ammeter, so it comes on when discharging and goes off when charging?

I'm sure there must be a simple way of doing this, even my A35 had one.

H
 

rapcom

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There is a nice LED unit available from Al Osborne which simply attaches to the ignition switch-controlled circuit, which glows different colours according to the voltage, thus acting as an ignition warning light and also as an indicator of the state of your battery/charging system. I have one on my bike, and it works well.
http://www.aoservices.co.uk/data/bsm.htm
It is available in panel mounting or handlebar mounting forms. Usual disclaimers, satisfied customer.
 

Howard

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There is a nice LED unit available from Al Osborne which simply attaches to the ignition switch-controlled circuit, which glows different colours according to the voltage, thus acting as an ignition warning light and also as an indicator of the state of your battery/charging system. I have one on my bike, and it works well.
http://www.aoservices.co.uk/data/bsm.htm
It is available in panel mounting or handlebar mounting forms. Usual disclaimers, satisfied customer.

Thanks for that. Seems a bit of overkill for what I want, but I'll have a closer look when I've got time.

H
 

Len Matthews

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Another method is to wire a low wattage bulb between the D terminal of the dynamo or regulator and coil side of your ignition switch. Not as sophisticated as Dick's suggestion but it works. If in doubt, study the Series D wiring diagram.
 

Howard

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Thanks Len. I knew there must be an easy way, I never thought to look at Series D. I've already got bulb holders in the speedo cowl (Egli) that do nothing, so it will even be free.

H
 

Howard

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Howard,

Is your system 12 volt?

For £15.40 Norton Commando specialists RGM motors sell a solid state warning light assimilator (RGM part No 130002). See http://www.rgmmotors.co.uk/home.htm and navigate to "Catalogue", then "Electrical Cont'd - Switches & Starter Motor" and it is the ninth item down from the top of page 1.

This device is designed to switch off a standard warning light bulb (i.e. up to 3W) when the input voltage reaches in excess of 12.3 volts with about 200mV hysteresis. It is designed to be a universal device suitable for any 12 volt system be that car, motorcycle or whatever. This 3 wire unit is approx 20mm x 20mm x 12mm and comes with wiring instructions.

As Dick has said, usual disclaimers apply.

Thanks.
I'm going with the Series D idea for now. I just need a couple of wires for that - everything else is in place, and all I need is an "idiot" warning lamp, flat batteries and filling diesel cars with petrol seem to be my forte this year!!!!!!!!!!!!!!!!

H
 

b'knighted

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Whilst not wishing to disagree with a man of Len’s knowledge and experience I have always been under the impression that mechanical regulators had terminal specifically wired to run the charge indicator light that we commonly called the ignition warning light. When converting to alternator, the exciter wire is fed from the ignition switch through the warning light. As Howard is using a solid state regulator I’d expect the addition of an additional warning lamp to confuse the electronics. A simple ignition warning led to advise that the ignition is on, unrelated to charging is the easiest thing to arrange, requiring a discrete led fed by tiny wires probably through a resistor. I'd expect the ammeter voltage and current to burn out an led instantly.
I used to fit the Norton type assimilator to give idiot lights on alternator triumphs, but never considered their use with dynamo. The AO led device recommended by rapcom works as a voltmeter and although more expensive than a simple led gives information on battery voltage before starting and while running. Its colour and/or rate of flashing can advise battery state from low voltage through to overcharging. The dash mounting version is a largish led (probably 10mm) on thin wires from a small control box which is wired to live and earth. On my Comet the control box lives in the headlight with the thin wires taped to the outside of the shell and the led hidden between left headlamp brackets and shell. My tax disc is on that bolt and these bits conspire to hide the led, except from the rider. It is a much better indicator of what is going on than is the ammeter. I use another on the Knight as a charge indicator with only the discharge running through the ammeter. The Battery Status Monitors are available in 6 and12volt versions - http://www.aoservices.co.uk/data/bsm.htm . As with rapcom “Usual disclaimers, satisfied customer.”

Cheers,
 

rapcom

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I probably bought a later version of the Al Osborn LED BSM, as mine has no separate control box, just two wires (pos and neg), going to the LED holder/mounting/bezel. Presumably the gubbins that used to be in the external box have got smaller and are now in the mounting.
 

Tom Gaynor

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The Sunbeam S7 has an ignition light, goes out when charging starts, and although I now have an electronic regulator, the FADE box (wonderful name) was same as any other. One side of the ignition light is fed from the D dynamo connection and the D FADE box connection, the other side goes to the coil whence to the ignition switch, whence to the battery. (I merely report this. I don't pretend to understand it.)
I bought a 12 v red flashing LED from VWP, mainly to remind me the ignition on my Vincent was switched on. A secondary function was that it looked as though the bike had an alarm fitted. This light went on when I switched ignition on (thus powering the starter and connecting Alton to battery) and stayed on until I switched it off. It did not however have any resistor fitted, at least not by me. I have an ignition switch because Alton recommend a switch, else apparently the Alton will slowly drain the battery if the bike is left dormant. The Vin electrics don't include sparks: I use a mag for that.
 
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John Appleton

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(I merely report this. I don't pretend to understand it.)
.[/QUOTE]
Easy one this Tom. Both you and Len are correct. Take a feed from the ignition switch. Turn ignition "ON" feed becomes positive. Take this positive feed to one side of a bulb. Take other side of bulb and earth it through the coils of the dynamo. Start the engine and the coils of the dynamo start to produce positive current. As the voltage starts to rise the bulb will dim to the point where it goes out , when the voltage in the coils is equal to the positive feed to the bulb and it is no longer possible for it to earth through the coils. Shut down the revs and the dynamo voltage drops below battery voltage and the bulb starts to glow. Your famous FADE box was sometimes fitted with an additional terminal marked WL (warning light). This was just a spur to the D terminal, and was just a convienient place to hook the return wire from the bulb. All of this applies to positive earth machines as well as negative earth. John
 
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