Accurate voltage readings from accessory harness when heated grips turned on ?

ett

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Hey guys need some electrical advice for hooking up my Kuryakan LED voltage meter.
I'm not very electrically literate. I understand positive, negative, and ground. And that's about it. :(


I scavenged my Kuryakan LED voltage meter from my old GSXR.
When I first installed that meter on my GSXR years ago.
Before I decided upon where I wanted it permanently mounted.
I took a Red Green method of temporarily connecting it's power leads.
By simply shoving them into the backside of the main dashboard electrical connector under the fairing.
But that crude, temporary connection worked so well. That it stayed connected that way for over 200,000 miles.

Today I attempted to connect that meter to my NT.
Since my NT has the accessory harness with both the 12V accessory socket, and heated grips attached to it.
I thought the meter could also be attached to the accessory harness.
And I thought I'd try the same temporary connection that I used on my GSXR. ie. simply shove the leads into the back of an electrical connector.
But neither the accessory harness's electrical connector or any other electrical connector under the fairing. Are designed in such a way that I can shove the meter's power leads into the back of them.
So I am going to have to actually connect the meter's leads correctly and splice them into the accessory harness's wires.

But before I do that.
Will the meter give accurate readings while the heated grips are turned on ?


Thanks;
--ET
 

Phil Tarman

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ET, I'm hardly an electrical genius either, but I'm pretty sure that wherever you connect the voltage meter, it'll give you accurate voltage readings either with the heated grips on or off.

The heated grips themselves work as a voltage meter, too. If you're not charging your battery, you'll notice that the heated grip indicator LEDs will blink. And when they're blinking, the heated grips quit heating until you get back up into a positive charging mode.

I've got the Kisan Chargeguard which wires directly to the battery and it shows decreased voltage when I'm running my electrical stuff. I can run my Warm'n'Safe heated jacket, my Denali D1 driving lights and my heated handgrips and show 13.2-13.8V depending on rpm. When I'm below about 2K rpm, my voltage drops down into the low-to-mid 12V range with all that stuff on. If I've got everything turned on and then use high beam, I need to crank the heated jacket down below about 60-75% or the handgrips down to 3 lights or lower to keep charging.
 
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The best way to hook up a voltmeter would be to connect it to a 12 volt wire that does not have a large load (current draw) on it.
If it were hooked to say the same wire that powers a heated vest and gloves there would be a small voltage drop in the wire itself from the battery to where the meter is hooked up (caused by the resistance of the wire and the current from the heated gear).
So to get the most accurate reading pick a wire not powering any large loads such as headlight or heated gear.

Brad
 

mikesim

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The best way to wire it to get the most accurate indication of your electrical system's health is directly to the battery. Using any other method will subject the meter (in this case, an LED array) to the voltage drop across the circuit that it is attached to. It's only a few minutes more work and a few more feet of wire to do it right. My apologies to Red Green.

Mike
 

DirtFlier

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[..The best way to wire it to get the most accurate indication of your electrical system's health is directly to the battery...]

+1. Going directly to the battery is the only way to ensure a "clean" reading. I've never owned a street bike that wasn't a Honda so typically rewire an accessory so its wires match the factory stuff: black is positive and green is ground. Makes it easier for me if I have to troubleshoot a problem!
 
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Before you kook it directly to the battery you should be aware that means the meter itself will always be 'on' and draw a bit from the battery. I would never connect a permanent voltmeter directly to the battery, even if properly fused.

If you connect to a wire that is sized for the load, the meter reading will be accurate enough. For example, the ACC harness is 'rated' for 10A of load. If all you have connected to it are the grips, that is about 4A. So, the voltage drop due to resistance is very small. I would connect it there.

If you want to see what the difference is, then connect it up and then connect a meter directly to the battery to see what the difference is. On my current bike it is about 0.2V.

You should also know that as the bike's RPMS drop the voltage output of the alternator will drop. If you have heated grips and then add aux lights,higher output headlight, heated vest, etc, then you will show a higher drop at lower RPM's. You may even hit the point where you are not charging the battery at low RPM (which is why some of us mount the voltmeter in the first place).
 

RedLdr1

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For example, the ACC harness is 'rated' for 10A of load. If all you have connected to it are the grips, that is about 4A. So, the voltage drop due to resistance is very small. I would connect it there.
Just a reminder that unfortunately Honda, in their infinite wisdom, placed an in-line 5 Amp 3AG glass fuse in the accessory harness between the 10Amp Accessory Fuse, located in the Fuse Box, and the heated grips. That is the only 3AG glass fuse on the US OEM version of the NT I know of.... A 3AG fuse hidden behind the upper fairing was not one of their better ideas. I guess they had a bunch of old in line fuse holders they needed to get rid of....:rolleyes1:
 
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That's kinda surprising cause I had about 8A of accessories running on that harness on mine. Heated grips, aux lights, phone and GPS.

Or do you mean it was in the heated grip harness? That makes sense cause the grips should only pull 4A on maz.
 
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ett

ett

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That's kinda surprising cause I had about 8A of accessories running on that harness on mine. Heated grips, aux lights, phone and GPS.

Or do you mean it was in the heated grip harness? That makes sense cause the grips should only pull 4A on maz.
I seem to recall that when I was attempting to install my meter yesterday. That I saw that glass fuse.
And it was on the leads to the heated grips.

--ET
 

Phil Tarman

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That would make sense, Wayne, but I think it's on the left side.
 
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ett

ett

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...
The heated grips themselves work as a voltage meter, too. If you're not charging your battery, you'll notice that the heated grip indicator LEDs will blink. And when they're blinking, the heated grips quit heating until you get back up into a positive charging mode.
...
I just experienced my grips LEDs blinking this morning commuting to work.
It was in the mid 20's so I had my Gerbings on full.
And I noticed towards the end of my 65 mile commute.
That when I had to stop for congested traffic; the LEDs would blink until I lowered or completely turned off some of my Gerbings.
HOWEVER; the LEDs did not blink when stopping for traffic near the beginning of my commute.

So could the heated grip LEDs blink when the battery gets low and not necessarily when the battery is getting a negative charge ?

Thanks;
--ET
 

Phil Tarman

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I have no idea...you'll have to get a reply from somebody who understands electricity. I'm still a believer in the old English theories that Lucas is the Prince of Darkness and that electricity quits working when something lets the smoke out of the wires.
 

DirtFlier

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[...Before you kook it directly to the battery you should be aware that means the meter itself will always be 'on' and draw a bit from the battery. I would never connect a permanent voltmeter directly to the battery, even if properly fused...]

I have my voltmeter tagged into the same subharness that brings 12V to the Powerlet on the handlebar clamp. It is a switch ON circuit (via relay) with an inline fuse.

ps. Happy Thanksgiving to all and remember to push away from the table after one serving!
 
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This is an interesting one, but, would have to know more about how the LED's are set up. Typically they are set to sense voltage, not whether or not the alternator is charging. What is the capacity of the charging system and how much extra stuff do you have hooked up. Grips take 2-4A. Gloves usually 4A. Aux LED lights 2-4A (halogens would be 4-8A). At idle the alternator is only putting out about half the rated output (or lower).

So, you start out with a fresh battery and start riding. If you have a lot of load and are in traffic a lot, then you will slowly drain down the battery during your commute. The problem is idle time vs rolling time. When you are at idle you are probably not charging at all and are probably losing capacity on the battery. This is a problem I have with the Goose.

The solution is to keep a bit of throttle on when sitting at lights. 1500 rpm should do it. Then you at least keep the battery from losing current during stoplights.

If you have a lot of extra accessories on the bike I would get a voltmeter. I have a cheap one from HF ($5) that I "cleverly" :) broke apart and installed in the dash. 6LEDs tell me where I am at. You can get easier to install ones from other places for more money.
 

DirtFlier

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[At idle the alternator is only putting out about half the rated output (or lower).]

The "break even" RPM for the charging system on modern Hondas is pretty low. On my NT it registers around 13.6V at idle and once underway it gets to 14.2/14.3V. The only time the voltage drops into the 12s is with key ON but the engine not running.
 
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Just a reminder that unfortunately Honda, in their infinite wisdom, placed an in-line 5 Amp 3AG glass fuse in the accessory harness between the 10Amp Accessory Fuse, located in the Fuse Box, and the heated grips. That is the only 3AG glass fuse on the US OEM version of the NT I know of.... A 3AG fuse hidden behind the upper fairing was not one of their better ideas. I guess they had a bunch of old in line fuse holders they needed to get rid of....:rolleyes1:
The extra glass fuse, though a PITA, is good electrical practice. A short in the hand grip wiring will not take down any other accessories such as auxiliary (am I the only one here who wants to put a second "l" in "auxiliary"?) lights.

[ I've never owned a street bike that wasn't a Honda so typically rewire an accessory so its wires match the factory stuff: black is positive and green is ground. Makes it easier for me if I have to troubleshoot a problem!
I am glad that Yamaha, at least on the FJR, uses more common wiring conventions. Red & red with tracer (that's what we in the electronics business call the secondary wiring color) is generally 12 volts and black & black with tracer is for ground and returns.

I have no idea...you'll have to get a reply from somebody who understands electricity. I'm still a believer in the old English theories that Lucas is the Prince of Darkness]
Lucas just had your safety in mind. He didn't want your riding after dark. :rolleyes1:
and that electricity quits working when something lets the smoke out of the wires.
A not uncommon theory among the electrically illiterate. :smile:
 
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RedLdr1

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The extra glass fuse, though a PITA, is good electrical practice.
I don't dispute the fusing the circuit. But IMHO a better practice would be to use an in-line fuse holder that uses the same type fuses as everything else on the bike.
 
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