Charging system gauge question.....

[1BigDog]

I just installed the Argus Battery Bug and it works great. 100% battery capacity and voltage reads between 13.7 and 14 while running. Drops down to 13.2 when parked.

 

At the same time I disconnected my Signal Dynamics charging indicator to be replaced by a digital meter. Here is where im seeing differences in the charging rate and where my questions lie.

 

As stated, the Argus is showing full charging. This gauge mounts directly to the + &- side of the battery for a direct read. The digital gauge is wired to a ground and the + lead is tapped into the ignition wire under the fairing. This is where im getting a lower reading from the digital gauge. 12.9 while running down to 12.2 fully loaded with all switches and lights on. Yet the Argus BB shows the charging volts at the battery in the 13 range. Did I do something wrong here? Why would there be such a difference in readings?

 

Is there a better place to hook up this digital gauge other than the ignition wire? Its the pink with yellow striped wire. My driving lights are also tapped into this line.

 

Help!!!!

[1BigDog]

No one has any ideas??

[KeithR]

Sorry can't help with the tech info but I am curious where you mounted the Battery Bug? I plan to install mine this weekend.

 

Thanks

Keith

[short-haul]

You will always have a voltage drop through a connector and switch . It is usually .03 volts for each connector and switch.

You will also have a voltage drop at the faring when things are turned on 1-2 volts is very possible due to the amp draw of these systems and the marginal size wiring that all manufacturers use.

That means at the battery you could have 13 volts and at the fairings power source only show 11 volts

So the best cure is run a ground and hot circuit to the battery from the fairing to get a proper reading on a voltage gage or battery bug.

Hope this helps

[Owen]

There are two possible sources for the voltage discrepancy. Easiest way to find it is with a volt meter. Connect the VOM (volt-ohm-meter) neg lead to the battery neg terminal, VOM pos lead to your voltmeter connection point on the ignition wire. Are the readings very close to the same voltage? If no, then check/clean/repair the ground connection between the faring and the battery. If yes, then the ground connection between the battery and the faring area is good. Next, connect the VOM pos lead to the battery pos terminal. Connect the VOM neg lead to the neg connection point of your voltmeter in the faring. Are the readings very close to the same voltage? If no, then the ignition wire voltage is being dropped by something in that line. A probable source is the actual ignition switch, these do fail by the way, has dirty/corroded contacts. As mentioned before, you can only run so much current on a line based on the wire diameter and switch rating. That is why most add on items you want to operate only when the ignition is on should be routed from the battery through a relay to the load. Your connection point of the voltmeter you are installing should be based upon what you want to monitor, ie. actual battery voltage, (connect it directly to the battery) or accessory/ignition voltage, (connect it to the switched ignition line).

 

Hope this helps.

[MikeWa]

There is a resistance in the circuit. it is located either between the two positive connections or between the two ground,neg, connections. To find it use your DVOM voltmeter. For this test positive and negative on the meter no longer matter so ignore the test lead wire color polarity.

 

To test the positive side of the circuit place one of your voltmeter leads at each of the positive points where your two gauges are connected. That is the black lead to one positive connection and the red lead to the other positive connection. With the key in the on position the reading should be less than .3 volts. Any reading above 0 is the result of resistance will course your gauges to show a different voltage by the amount of the reading.

 

To test the negative side of the circuit place one of your voltmeter leads at each of the negative points where your two gauges are connected. That is the black lead to one negative connection and the red lead to the other negative connection. With the key in the on position the reading should be less than .3 volts. Any reading above 0 is the result of resistance will cause your gauges to show a different voltage by the amount of the reading.

 

This is called a voltage drop test. You might also want to connect your two gauges to the same place and see if they are calibrated the same.

Mike

[1BigDog]

I tried the ground connection thing. I had two different ground wires at the same point. Once I seperated them, the charging gauge went back up into the 13 range. Too bad I ran out of time to properly mount the gauge. That will be a project for another day. At least I now know what the problem was. Thanks for the suggestions.

[1BigDog]

Sorry can't help with the tech info but I am curious where you mounted the Battery Bug? I plan to install mine this weekend.

 

Thanks

Keith

 

Keith, heres the link with pics of the battery bug installed. http://www.venturerider.org/forum/showthread.php?t=48338

 

I chose to mount it on the right side of the rear fender, out of the way but still visible if needed to check. I felt it was too big and ugly to mount it on the dash area. I think its a great addition to our bikes, or any bike. My battery is showing 100% health and 12.9 after sitting for 2 days. Reads 13.8 when running. Supposed to let you know when your battery is near the end of its useful life.