finding a ground

[DEEBS47Chief1991]

In the case of a small draw off the battery at rest you would possibly need to read micro amps (0.001A).

[dukekleman]

The Fluke 115, I suggest, has the capabilities to do all the proper fundamental testing required.
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Hope this helps ,

Duke Kleman

[BoschZEV]

In the case of a small draw off the battery at rest you would possibly need to read micro amps (0.001A).

You are mixing up micro and milli (0.001A is a milli-Amp, not a micro-Amp). Even a small 6 A-hr. battery would take over 600 years to drain with a 1 micro-Amp leak.

As for Duke's Fluke 115, although multimeters of this type have the necessary sensitivity, they require opening multiple circuits to insert the meter in-line in each of them separately to troubleshoot. Not only is that time-consuming and inconvenient, for some circuits it can be nearly impossible. In contrast, an AC/DC clamp-on meter like the Fluke CM100 mentioned in Duke's earlier post is very much more useful since meters of this type quickly clamp around existing wires without having to undo any of them.

While Fluke makes excellent, rugged meters, other companies make ones that are completely adequate for "non-professional" use, at much lower cost.

[BoschZEV]

The photograph shows how fast and easy it was with a clamp-on meter to confirm that my tail light circuit doesn't have a short that's draining the battery. Instead, imagine how much more difficult and time-consuming it would be to disassemble the taillight and unsolder the connections in order to insert a standard multimeter like the Fluke 115 in the circuit to make the same measurement.

ClampOnMeter.jpg

[dukekleman]

The photograph shows how fast and easy it was with a clamp-on meter to confirm that my tail light circuit doesn't have a short that's draining the battery. Instead, imagine how much more difficult and time-consuming it would be to disassemble the taillight and unsolder the connections in order to insert a standard multimeter like the Fluke 115 in the circuit to make the same measurement.

ClampOnMeter.jpg

The General Technologies CM 600 and CM 100 are very nice Amp clamps. The have proven themselves very reliable in our training facilities. We generally use them diagnosing Dynamic amperage because of the efficiency in time as you mentioned.

If a person doesn't want to invest in multiple tools,the Fluke 115 is a good option being it has all the capabilities to diagnose a simple key Off amp draw as well as many other electrical diagnostic tests.

You can simply hook the Fluke in series on the negative ground cable/wire and observe any presence of a Key Off amp draw. If an key Off Amp draw exists, using your example above, just simply unplug the taillight bulb and observe any change in the key Off amp draw. No need to unsolder wires, etc...

Hope this helps,

Duke Kleman

[BoschZEV]

hook the Fluke in series on the negative ground cable/wire ... simply unplug the taillight bulb and observe any change in the key Off amp draw. No need to unsolder wires, etc...

I hate to disagree. But…

In your example, if there were a short either along the taillight wire or in the socket, unplugging the bulb would not change the current measured by your Fluke, which would cause someone to incorrectly eliminate the taillight circuit as the source of the problem.

The power of a clamp-on ammeter is it only takes seconds to move from position-to-position. Located as in my photograph it would eliminate the socket (and wiring between the meter and socket), and moving it closer to the other end of the taillight wire would either eliminate, or confirm, a short somewhere in the wire between there and the previous position of the meter.

I'm not at a loss for multimeters, not all of which are shown in the photograph below, and I certainly agree that they are required when working on motorcycles. However, for some purposes, a clamp-on ammeter is indispensable. Although the credit card-size meter at the bottom right doesn't have a current scale, I included it because I carry one of these with me when I ride because a large fraction of ride-ending problems on old motorcycles are electrical. Also, I included the analog meter in the bottom row, that I've had for nearly 60 years, not because it has a current scale, but because often an analog voltmeter is more useful for troubleshooting than a digital one (often, just seeing the needle flick out of the corner of my eye is more useful than being able to measure the voltage to three decimal places).

[BoschZEV]

DVMs.jpg

[dukekleman]

While I acknowledge and respect there maybe differing view points on this testing procedure matter, the testing procedure I presented for CScott's "key Off Parasitic draw" is supported by manufacturers guidelines and established Industry Standards.
These recommendations are based on extensive testing and practical application, and reflect best practices widely adopted across the Powersports Industry.

It would be wrong for me to assume or expect all others to have the vast amount of testing tools some of us have. Some of us have drawers, bench top's and even labs full of electrical test tools while the majority of the AMCA members asking for Technical support on this forum are not going to have these items.
Our entry level technicians are provided the following tooling shown below.
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This is entry level tooling they train with but once again, most people aren't going to have access to this in their current tool box.
My thought was to concentrate on a particular tool, the Fluke 115, as a fairly common tool that CScott could possibly access, affordably, and make his own diagnosis.
It would help us, help him, if we knew if and/or what key Off Parasitic draw exists???
As others have mentioned earlier, it may just be a battery issue. Perhaps even surface discharge.
Hopefully we can help CScott with his problem.

Duke Kleman

[BoschZEV]

My thought was to concentrate on a particular tool, the Fluke 115, as a fairly common tool that CScott could possibly access, affordably, and make his own diagnosis.

I won't argue about your "industry standards" or "best practices" statements, but I agree that most AMCA members won't have, and don't need, anything like the test instruments I have. However, for the $233 that Amazon shows for a Fluke 115, CScott and other AMCA members could have a quite serviceable multimeter with the same 10 A upper range as the Fluke, a clamp-on AC/DC ammeter (that also has Volts and Ohms ranges), and at least $150 left over.

As the earlier photograph shows, I own three (actually, four) Fluke multimeters, so I know and respect the brand. However, I would not recommend a motorcyclist who only has occasional need for electrical measurements spend the money needed to buy that brand rather than a perfectly serviceable alternative at a much lower price.

[dukekleman]

I agree with you.There is probably another brand(s) that will get the job done from Harbor freight or something...
Its that I do not have the experience, with any others, to give a recommendation of another Brand and model.
Hopefully he finds the problem quickly so that he can enjoy the riding season.

Duke Kleman