parasitic Datel?

I searched the hell out of this so kindly refrain from pelting me with fecal matter-I want to wire my cool new 2 wire led Datel meter directly to the battery-info on the board indicated that the most accurate reading is there. Since it would be on all the time would the constant draw be a problem? It can't pull to much juice.. The bike is always on a tender when in the garage..Tx

Depending on accuracy of the 2 wire Datel chosen the current draw will be a scant 7mA to 13mA (.007 to .013 amps). At 7mA it will take a bit less than a week to consume 1 amp of current. At 13mA it will take ~1/2 a week to consume 1 amp.

According to the datasheet, the Datel LED voltmeter draws 8mA on average, with a max of 13mA. At that rate, you shouldn't have a problem ever, with or without a battery tender.

Feel free to accept or reject the following advice as you see fit.

Do not do this "constant" connection to the battery. Trust me.

Wire the Datel positive (+) lead directly to the battery's positive post. You may insert a 1-amp fuse inline if you truly feel the need, but a "pure", unhindered, unencumbered connection using quality twisted-strand wiring would be optimal, ensuring it is insulated and even further encased in shrink-tube to prevent any chaffing issues.

Wire the Datel negative (-) lead to a *high-quality* toggle switch of your choosing, which is then connected directly to the battery's negative terminal. Place nothing else in between.

As I say, feel free to accept or reject the above as you see fit.

How does one discern a 'high quality' toggle switch from the garbage variety? And how much would it hurt things to have the negative wire coming from the datel go through a swithced relay?

SkooterG said:

How does one discern a 'high quality' toggle switch from the garbage variety? And how much would it hurt things to have the negative wire coming from the datel go through a swithced relay?

Click to expand...

I do the Zen thing to discern high-quality. Or... cost.

You could use a relay, sure. Voltage drop should be trivial. Should be.

Yet, every component (be it relay, barrier strip, fuse link connectors, what-have-you) in between the Datel and the battery post represents at least the opportunity to introduce resistance into the circuit over time (corrosion buildup, harmonic vibration affecting connector tightness, etc). The object of the game here is to get the absolute most accurate reading you can. Two relatively short wires (that run directly between the Datel connectors and the battery terminals) is about as good as it gets.

There are electrical equations and classroom theory that might suggest this pre-occupation with providing such a "pure", clean circuit to the Datel is overkill. <shrug> Okay. I am only offering my experience on this issue based upon many years and countless miles using the Datel on many different motorcycles.

In the Datel application any sealed automotive relay will be more than sufficient. In the case of a toggle switch, a metal framed, sealed switch will typically have a longer actuation life over a totally plastic switch. The metal frame not only provides better pivot life, it also provides better support for the contact's snap action. Unfortunately the average consumer can't get information about the electrical characteristics of most over the counter electrical parts.

If you are looking for quality electrical switching and distribution gear and won't faint at the price difference between a $2 and a $6 switch, it is hard to beat marine grade parts that can be found at places like this. The products are really weather proof and generally offer extended life as well as having good quality.

All things being equal, a higher amperage switch will have lower contact resistance (good) and a stronger snap action to hold the contacts solidly in, uhh, well, contact When you select a switch for a more demanding job than a Datel meter be sure that the contact ratings have some 'head room' over the expected load. Selecting a 5 amp switch for a steady 5 amp job is asking for long term trouble, a 10 amp switch would be a better choice.

Edited to add: On a motorcycle's electrical system the difference of just TWO volts is major -- 14.0 volts = good; 12.0 volts = your day/trip is about to be ruined. You don't want to squander 0.1 to 0.4 volts just in your meter's hook-up. Fortunately the Datel's tiny current draw goes a very long way to preventing excess voltage drops.

ionbeam said:

If you are looking for quality electrical switching and distribution gear and won't faint at the price difference between a $2 and a $6 switch, it is hard to beat marine grade parts that can be found at places like this. The products are really weather proof and generally offer extended life as well as having good quality.

Click to expand...

Excellent, Alan, as usual!

ionbeam said:

blah.....blah......blah.......electrical geek shit...........blah.........blah..........blah...........

Click to expand...

Damn dude! You gave me a woody!

As always, thanks for your detailed, informative response that confirms that yes, I know nuthink!

So specifically, which Datel is the bees knees? Which one is 'the' one to have?

[insert Link here]

While I applaud everyone's efforts to minimise voltage loss, I point out;

1. Switch the negative OR the positive, doesn't matter which.

2. Cheap switch, expensive switch, relay - doesn't matter much. A 13 milliamp load (presumably at 12 volts) implies internal resistance of slightly greater than 923 ohms. The WORST electrical switch out there provides less than 0.2 ohms of resistance. The impact on your 12 volt reading would be .0016 volts or thereabout.

Don't sweat it.

bramfrank said:

Cheap switch, expensive switch, relay - doesn't matter much.

Click to expand...

I think this particular "cheap vs. 'not' cheap" switch counterpoint implies longevity and resistance to failure, through poor design, poor weatherproofing, etc., rather than inital electrical resistance.

Since a motorcycle IS prone to Mother Nature's most egregious PMS rants, a high-quality switch designed for a marine evironment makes an incredible amount of sense.

But then, like SkooterG, I know nuthin'.

bramfrank said:

While I applaud everyone's efforts to minimise voltage loss, I point out;
1. Switch the negative OR the positive, doesn't matter which.

2. Cheap switch, expensive switch, relay - doesn't matter much. A 13 milliamp load (presumably at 12 volts) implies internal resistance of slightly greater than 923 ohms. The WORST electrical switch out there provides less than 0.2 ohms of resistance. The impact on your 12 volt reading would be .0016 volts or thereabout.

Don't sweat it.

Click to expand...

Yes, I agree, don't sweat the resistance of the switch, look for a good weather seal and long switch life action.

1. Doesn't matter (much). Depends on how it's done, do you want to leave a wire 'hot' (open ground) or cold (open power wire)?

2. Look for a SEALED switch or relay. I only suggest a way to find a switch whose contacts will have a long life. At the minuscule current level of the Datel meter contact resistance is a moot point.

[3.] Due to the normal fluctuations in voltage ignore all voltage reading in the 0.01 range. In fact, don't worry about readings that vary ± 0.200 to 0.300 volts until they go into the worry zone. Uhh, as long as you know those readings are accurate

I've been happy with this one by Lascar Electronics.



Clicky

I don't have one on my FJR yet, but I've had one of them on my Wing for ~80,000 miles.

Renegade said:

So specifically, which Datel is the bees knees? Which one is 'the' one to have?
[insert Link here]

Click to expand...

Below link is the *exact* Datel you want.... essential equipment for Iron Butt Riders on bikes like our FJR:

Datel DMS-20PC-1-DCM voltmeter

Do not get the blue version. Believe me. Trust me.

Do not get the 1/100th placement version. The last digit will be constantly changing, and will prove irritating and distracting in short order

The red XX.X version (DMS-20PC-1-DCM) is The One.



FJRichie and Ignacio stuck their Datel's in the right mirror.... very cool! FJRTech: Datel Voltmeter - Mirror Installation

Perfect, thanks.

So, what's wrong with the blue? I'm assuming sun/glare/maybe it's too bright at night?

But it's so sexy and matches the bike so much better?

I'll have the wifey put one in my stocking.

-MD

SkooterG said:

ionbeam said:

blah.....blah......blah.......electrical geek shit...........blah.........blah..........blah...........

Click to expand...

Damn dude! You gave me a woody!

Click to expand...

There can be no higher praise! (I guess)

Renegade said:

Perfect, thanks.
So, what's wrong with the blue? I'm assuming sun/glare/maybe it's too bright at night?

Click to expand...

The primary objection is the blue intensity at night. It is enormous.

For many years, I ran a blue Datel that wasn't a voltmeter... it was a ambient air thermometer (a "one-off" special, custom made... you won't find them in production unit). It was so frickin' bright sitting atop my Top Gun Shelf on the FJR, I was forced to place a piece of duct-tape over the face of the meter after sundown... and could *still* read the numbers plain as day! :blink:

Without the duct-tape over it at night... I would be bathed in a sea of blue light... I'd look like one of the Blue Men traveling down the road.... :lol:

Warchild said:

Renegade said:

So specifically, which Datel is the bees knees? Which one is 'the' one to have?
[insert Link here]

Click to expand...

Below link is the *exact* Datel you want.... essential equipment for Iron Butt Riders on bikes like our FJR:

Datel DMS-20PC-1-DCM voltmeter

Do not get the blue version. Believe me. Trust me.

Do not get the 1/100th placement version. The last digit will be constantly changing, and will prove irritating and distracting in short order

The red XX.X version (DMS-20PC-1-DCM) is The One.

<image snipped>

FJRichie and Ignacio stuck their Datel's in the right mirror.... very cool! FJRTech: Datel Voltmeter - Mirror Installation

Click to expand...

FWIW, I put mine in the mirror but think that I'd prefer it not be there and that's not a mod you can easily <ctrl><x>. I also found that I had to run a wire from the bolt & stud holding the mirror to the bike to the negative lead of the battery to get a good reliable connection. *shrug* Not sure why.

I stuck a waterproof push on, push off switch in one of the fairing panels to allow me to switch it on & off at will, but no relay. Works pretty well, though. I do wish there was a version with smaller "font," but that's just me. Next step: Electrosport stator.

Rancho