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VulcanE
05-18-2011, 11:27 AM
I installed a set of SunPro gauges in my fairing, and have a couple of questions about the volt meter. With switch on (engine not running) it reads 11 volts. Start the engine and it reads about 12 1/2 volts. I got out my VOM meter and checked at the battery, with switch on (engine not running), VOM says I got 12.8 volts, start the engine and the VOM says I got 14.1 volts at idle and it maintains the 14 volts up thru 3000 RPMs. My question is, why is there a difference between the gauge, and the VOM?
Thanks,
Cliff

recumbentbob
05-18-2011, 11:48 AM
The VOM should be right.
Either your sunPro guage is faulty or it's connected weird.

Check the voltage at the Sunpro connection with your VOM and see what you get.

Sin City Stan
05-18-2011, 12:09 PM
The VOM should be right.
Either your sunPro guage is faulty or it's connected weird.

Check the voltage at the Sunpro connection with your VOM and see what you get.

There may be a small calibration screw in the back of the gauge.

ringadingh
05-18-2011, 12:22 PM
Your meters both sound correct,you will get a different reading at the battery than you will at the gauge depending on where you tapped into the circuit.
If your getting a reading of around 14.1 while riding you should be fine

macmac
05-18-2011, 12:46 PM
With the VOM set to 20 dcv, prick the battery (+) with the red lead, and with the black lead gauge on prick the 'IN' wire, and you should get 0 dcv. If you don't there is a problem in the wire/connections. You may well get a reading of 2.?? dcv .

Or the gauge isn't accurate but that brand should be.

cactusjack
05-18-2011, 01:36 PM
One of them is not as accurate as the other. You hand-held VOM should be more precise.

Jared
05-18-2011, 03:34 PM
I have a cheap Kuryakyn volt meter and it reads off too.

macmac
05-18-2011, 03:53 PM
There were Sun Pro gauges on the Hamilton Test Dyno I used to run and the gauges on that were very good over all. Maybe this is a sub line or something, but still a fairly accurate voltmeter isn't that hard to build. I wouldn't accept a 2 volt loss with out looking for a reason.

The cheapo ciggy butt socket volt meter I run is very accurate, until it gets bumped off it's seat then it spazes out, but re-set with a swift knock. I get nervouse when I see less than 13.5 dcv. I only see that with both sets of passing lights ON, when I go moose huntin'.

ringadingh
05-18-2011, 04:52 PM
Where is the gauge connected on the bike, one wire to ground and where did you connect the other wire?

macmac
05-18-2011, 04:54 PM
Ring that might be it. That meter would want a switched wire off line with other stuff.

ringadingh
05-18-2011, 05:26 PM
Im pretty sure that it because I just went through that on my bike about three weeks ago.
After I added my new tailights my gauge went from reading about 13.8 to 12.5 I found I had too many things tied into the tailight circuit. I installed a auxillary fuse panel, seperated some circuits, and now the gauge reads 14.2 most of the time, or I mean did.

macmac
05-18-2011, 07:06 PM
My cheap junk meter is the only thing on the white/blue acc wire in the lamp bucket. It reads battery volts 24/7.

VulcanE
05-18-2011, 11:05 PM
Hi folks, I'm back http://s2.images.proboards.com/grin.gif Thanks for all the pointers. I do have it wired separate. After I made my thread I called SunPro (aka Actron) and spoke with technical support. He said that it sounded like it was out of calibration. He got my name and address and said they would ship me a new one today. He didn't even ask how long I've had it, where I bought it or anything. I presume that there will be instructions on what to do with the old one, in with the new one. I was VERY impressed with their customer service/support.

macmac
05-19-2011, 09:21 AM
If this was a quailty meter, which I can only assume it is, they will want to stand by their work.

Unless this is a new co, with a old name, or some other life fubarr happend to cheapen meters, that was a top notch co for making meters, and was used by Snap On and Hamilton Test Equip for years.......

What I don't know is like sneakers. You can get good sneakers and bad sneakers with the same name, but one is a knock off of the real thing.

VulcanE
05-19-2011, 10:07 AM
Actually Mac, SunPro is still owned by Snap-on, and is located in Cleveland Ohio. Snap-on also owns Actron and AutoXray, both are heavy into automotive scanners and diagnostics tools.

macmac
05-19-2011, 11:07 AM
Ah, well then that gauge is as i thought, a quaility instrument. They should insist it works well for you.