Misc: Charging Systems Chinamo over charging.

Simon Dinsdale

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The DVR2 regulator unit is usually set to max 14.2-14.3V output. If the output charge voltage is measured above that with a seperate voltmeter that is known to be accurate then its either the regulator is toast or the wiring in the dynamo itself is wrong ie is there a link accidently shorting where the regulator sits in the field circuit.

It doesn't matter what the battery is as the output of the regulator is set by the regulator and not the battery.

Did you rewire the dynamo connections correctly when you fitted the DVR2 regulator as they connect differently to a JG. I seem to remember the JG regulator fits between the field winding and earth with the top of the field permantly connected to D. Where as the DVR2 sits between the top of the field and D and the bottom of the field is permanently connected to earth.

I used to build my own electronic dynamo regulators but now use the DVR2 which I have being running for approx 10 years on several bikes without a single problem. I'm just a satisfied customer.

Simon
 

john998

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Hello, sorry I don't have a working hydrometer.
The internal wiring has been changed to suit the dvr2 regulator, I use one on my solo and it works well. The solo has a Miller dynomo which leaves me wondering if some characteristic in the Chinamo doesn't suit the dvr2.
John.
 

Peter Holmes

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Is the additional .2 of a volt likely to cause you any problems, 14.3 - 14.5 albeit you say over 14.5, but presumedly not 14.6, seems a fairly small margin
 

mercurycrest

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Hello, sorry I don't have a working hydrometer.
The internal wiring has been changed to suit the dvr2 regulator, I use one on my solo and it works well. The solo has a Miller dynomo which leaves me wondering if some characteristic in the Chinamo doesn't suit the dvr2.
John.
I agree with Simon's comments. I have a Chinamo on my D running 6 volts with the original regulator. It shows a good 3-4 amp charge and near enough 7-1/2V and works just fine. Could it be we've got used to sub par charging systems for so long that a proper operating one alarms us? That Chinamo on 12V is easily good for 130 watts. With an 8 amp charge that's only 116 Watts @ 14.5V and if your battery isn't at 1.265 specific gravity, it'll want to charge.
 

James B

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I had a similar experience sorting out the charging: a miller regulator modified to use an electronic regulator

I ended up making a 3 channel volt meter so that I could see the voltage at battery, armature and field coil all at the same time.
image.jpg


You’d expect a fully charged battery to be around 6v ish, and the armature voltage to go up to around 7.2 ish

When the bike is not running, both the armature and field voltages should be zero, otherwise the regulator is allowing the battery to be discharged

At idle, the field coil will be driven by the battery voltage and the armature will be at whatever is being generated. Will be lower than the battery voltage

As the engine revs rise the armature volts will rise. The regulator will vary/reduce the field coil voltage to limit the armature voltage to the regulation level of approx 7.5v
The voltage at the battery will also rise to this regulation voltage, and charging occurs


Common faults from regulators include:
Field coil not driven so no or little armature output and poor or no charging. Magnetism remaining in the dynamo will usually result in some output and this is what the regulator uses to detect the bike is running - so flashing is important
Field coil always driven and not regulated. Results in overcharging
Field and armature not disconnected when engine not running. Results in battery discharged through dynamo over time. Often means a deeply discharged battery - which may not be possible to resurrect

On mine, I diagnosed the lack of disconnection when not running. It might have been overcharging as well

The meters came from eBay and around £10 for the 3. I’d encourage anyone with dynamo charging worries to make one of these. It allows understanding of exactly what is going on. It’s all too easy to chase around stuff that is working just fine

Change the voltages as appropriate if you have decided to run a 12v system. I’ve retained a 6v configuration at least for now. I’m using a dvr2 as well, which can be configured either way
 

john998

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Hello, many thanks for all the input. I think my problem is that the solo with the same regulator but Miller dynomo hardly shows a charge. It has all LED lamps. I had to refit a ordinary head lamp bulb to convince my self that it would balance a load. It works perfectly.
The outfit with the same regulator but Chinamo still pushes 6 to 8 amps at all times at any higher RPM. It works fine, just as well as it has coil ignition. It has done this for some years , and it does no apparent harm except perhaps to the battery. John.
 

Simon Dinsdale

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John
Here is a quick test. Disconnect the external F wire between the regulator and the dynamo and insulate any bare connections. Then start the bike up and see what the charging is doing. If there is no charge then the fault points to the regulator and if it still charges 6A-8A then the fault is in the dynamo in the form of an internal short between the F & D terminals or wiring inside the dynamo.

I have run a Chinamo with a DVR2 in the past with no problems and once the battery is fully charged it should settle down to less than 1A if no lights are on.
 

Simon Dinsdale

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Is the additional .2 of a volt likely to cause you any problems, 14.3 - 14.5 albeit you say over 14.5, but presumedly not 14.6, seems a fairly small margin
No the odd 0.2V is not a problem and most cheap Voltmeters would struggle to measure to within 0.2V accurately. If the regulator is toast then if the bike revs are high enough the output voltage of the regulator could rise above 15V easily.

Simon
 

Pete Appleton

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Sounds to me as though you have the ignition feed coming from the wrong side of the ammeter. The ammeter is reading the power that you are consuming rather than just what is going into the battery.
If you have points ignition, turn the ignition on and turn the engine over slowly, you should see the ammeter showing a discharge when the points close. If you don't see that then the ignition is wired to the battery side of the ammeter.

Just trying to think of something that would be unchanged when swapping the charging system over if the fault has stayed the same.

Of course if it suddenly started doing this and you hadn't changed any wiring then it wont be that.
 

john998

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Hello, I have just checked the voltage at the field coil at tick over , about 4 volts rising to 12 volts at higher RPM.
The ammeter does show a discharge with point close engine off.
I am now wondering about my wiring but as I said this problem was the same with the JG regulator. When my energy level increase I will pull the battery platform of again and check the regulator connections.
John.
 
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