Ammeter wiring
- Thread starter Danno
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So, with engine stopped, you switch the lights on and it shows a discharge?
And if you start the engine and rev it up with lights on, that discharge doesn't change?
And if you start the engine and rev it up with lights on, that discharge doesn't change?
texasSlick
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Triton Thrasher said:
Next test: cross switch the wires on the ammeter terminals. It will not hurt anything if the ammeter is reversed wired, but it should reversed the direction of ammeter movement.
Slick
o0norton0o
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In a previous ammeter discussion here I said something similar about my ammeter's pointer. It seems to show a drain pretty obviously when the bike isn't running and the lights are on, but it barely moves in the positive direction to show it's charging when the bike is running. I've ridden my bike around all day, so I know that the bike's electrical system is charging, but the ammeter really doesn't show much in the way of moving into the positive direction, but it does move ever so slightly there when the bike's RPM's climb over 2,500.
One of the things you do see and get used to seeing is when you come to a stop light and you are idling, the ammeter will show a state of discharge at low RPM's. As soon as the light goes green and your RPM's climb when you get going, the needle moves back to show the charging system is doing it's work. If you put on your blinker, you will notice the ammeter will bounce with every flash of the blinking light which also shows that it's working.... It just doesn't move into the positive very much unless your battery is drained (I supose) It's something I've gotten used to seeing.
In that other thread, Jim suggested putting a voltmeter in the ammeter's place since you could see charging state reflected in a voltage increase, and voltage is also a better indicator of the state of your battery, rather than just seeing the direction of current flow on an ammeter which always looks like it's near zero when your battery is charged.
It's been a long time since I wired my ammeter, but I just added it to the circuitry exactly as it's shown in the electrical schematic diagram on a norton that had an ammeter. I actually drilled the center hole in my headlight shell for the ammeter diameter (1 5/8" if I recall) and mounted it where I could see it easily.
One of the things you do see and get used to seeing is when you come to a stop light and you are idling, the ammeter will show a state of discharge at low RPM's. As soon as the light goes green and your RPM's climb when you get going, the needle moves back to show the charging system is doing it's work. If you put on your blinker, you will notice the ammeter will bounce with every flash of the blinking light which also shows that it's working.... It just doesn't move into the positive very much unless your battery is drained (I supose) It's something I've gotten used to seeing.
In that other thread, Jim suggested putting a voltmeter in the ammeter's place since you could see charging state reflected in a voltage increase, and voltage is also a better indicator of the state of your battery, rather than just seeing the direction of current flow on an ammeter which always looks like it's near zero when your battery is charged.
It's been a long time since I wired my ammeter, but I just added it to the circuitry exactly as it's shown in the electrical schematic diagram on a norton that had an ammeter. I actually drilled the center hole in my headlight shell for the ammeter diameter (1 5/8" if I recall) and mounted it where I could see it easily.
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I think what tends to be overlooked (and why I asked Danno the questions I did) is that for the ammeter to register a charge, the charge output wire from either the rectifier or a reg/rec unit must be connected to the negative side of the ammeter.
The pre-'71 diagram below shows it (NW from the rectifier) but on the later models, charge output goes to brown/blue NU) as there's no ammeter, so anyone fitting an ammeter to a '71-on model needs to move the charge output connection if they want it to show when the system is charging.
The pre-'71 diagram below shows it (NW from the rectifier) but on the later models, charge output goes to brown/blue NU) as there's no ammeter, so anyone fitting an ammeter to a '71-on model needs to move the charge output connection if they want it to show when the system is charging.
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o0norton0o said:
You're right that the discharge indication should decrease to zero as revs rise and that not having much indication of charge may not be any problem at all.
But don't wire a voltmeter directly in place of the ammeter! A voltmeter must be connected differently.
DogT
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Heed what L.A.B. says first. Second, if your battery is in good charge, you will never get a large indication of charge. Only when your battery has run down will it then show charging with higher rpms. Sit at idle with the lights on and it should discharge, then when you increase the RPMs you should see a charge for a bit of time until the battery has reached full charge. Then the charge rate will drop back to nearly nothing. Hitting the brakes or horn should immediately show a rather large discharge.
If your battery is poor, it may never take a good charge and that may also indicate not much charge, but will also not show much discharge, but by that point, your EI will probably start malfunctioning.
Nothing wrong with wiring a voltmeter like the ammeter, it's just going to read voltage that's hard to understand, it won't hurt the voltmeter. Now hooking up an ammeter like a voltmeter, something you don't want to do, you can likely damage the ammeter.
If your battery is poor, it may never take a good charge and that may also indicate not much charge, but will also not show much discharge, but by that point, your EI will probably start malfunctioning.
Nothing wrong with wiring a voltmeter like the ammeter, it's just going to read voltage that's hard to understand, it won't hurt the voltmeter. Now hooking up an ammeter like a voltmeter, something you don't want to do, you can likely damage the ammeter.
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The battery (Bikemaster Tru-gel) is fine and hooking up the charger after 30 miles of varied riding shows it is being charged by the system. I have an older Boyer and I know when the battery gets low, no spark. I need to get in some longer rides, but at this point, only the ammeter doesn't seem functioning correctly. I have it wired with the hot lead off the battery going to the meter and then to the ignition switch. Should the meter be wired BEFORE the battery, i.e. between the reg/rec and the negative with the hot lead going directly to the ignition switch?
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Danno said:
As I said previously:.......for the ammeter to register a charge, the charge output wire from either the rectifier or a reg/rec unit must be connected to the negative side of the ammeter (see wiring diagram in my previous post).
So, connect the reg/rec negative wire (assuming positive earth/ground) to the ignition switch side of the ammeter.
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All done. The ammeter now flutters between charge and discharge like a proper British gauge should. At idle with the headlight on, it drops to about -5 and then goes to +5 cruising above 3500 rpm. After a bit, it zeroes out and then hunts between -1 and +1 amps.
o0norton0o
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Danno said:
I've had an ammeter for years and that discription is exactly how my ammeter has opperated. Although,... oddly enough yesterday the needle was momentarily swinging to strongly charging as I pulled away from a light in a low RPM state. When I pulled away the needle swung to a strong charging position then gradually swung back down towards the +1 mark, after about 10 seconds.
I'm going to check my battery... maybe one cell is low on water or the battery is nearing the end of it's life... It's usually fluttering back and forth around zero, so I 'm wondering why...
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I remember seeing them on old Triumphs and BSAs. Once the engine started, the needle would bounce crazily about, never giving a decent reading, just letting you know it was alive. This one (British-made, but not Lucas) seems to have some damping that keeps it from fluttering like a dying moth.
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DogT said:
You can't put a voltmeter in series with the battery! Almost no current will get in or out of the battery, because of the very high resistance of a voltmeter.
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