Bought a voltmeter - now what?

[Vidi]

Ok The subject line is a bit misleading.

I just have a couple of questions about it.

1) I had three 1.5 LR attys reading over 100. They were thrown in the trash, but what does that high number signify?


2) I had a couple that metered at 1.0. What does that signify?


3) there are some great tutorials on HOW to check an atty with a meter but I have yet to find one that explains in detail what ranges are good, bad or worrysome. Anyone have a link to a chart or can post what an acceptable range would be?


Thank you in advance

 

[Stosh]

Checking resistance is easy, if the atty or carto is supposed to be 2.0 ohms, the meter should read 2.0... If they are 1.7 ohm, the meter should be the about the same, or within a couple tenths.

A high reading (100 or more) means there is much more resistance than there should be, and the heating wire in the atty is toast. A very low reading, approaching zero, means the atty is shorted, also toasted, and can harm your batteries.

 

[Jaguar G]

What Stosh said.

Also, you need to "zero" your meter to find the base line. Touch your leads together and see what ohms it reads, usually 0.1 - 0.5. You take that "zero" out by subtracting it from what you get when you measure the atty. Say you have a 0.3 zero, and your meter reads 2.5 ohms across the atty, you actually have a 2.2 ohms.

The need for "zeroing" the meter is because typically ohm meters are not meant for these low reading, electronics resistors are 50 ohms to 30,000,000 ohms (30MΩ), and most meters designed with these ranges in mind. Finding resistors that read lower than 3 or 4 ohms typically means a "short" in the electronics industry, precise measurement of this range is not really considered. The combination of the leads and the connections where the leads go into the meter causes this loss of accuracy at these low readings.

To answer your specific questions;

1. 100 signifies the coil is basically broken. There may be some juice or contaminant that cause it to read less than "open" but they should be in the 1.5 - 4.0 range.

2. 1.0 seems low, too low. An atty at 1 ohm and battery at 3.7 volts would give you 13.69 watts of power, (V^2/ohm) which is pretty high for vaping and will snuff a battery in no time. I am not an expert in all things vaping, but I don't know anyone selling 1.0 ohm attys.

3. I don't know of any tutorials but let me see if I can help. Do the "zero" step above then measure the atty/carto by placing one lead on the bottom center pin of the atty/carto and the other on the on the threads. A good measurement for attys/cartos would be for low is 1.4 - 2.0 ohms, regular is 2.0 - 3.0, high is 3.0 - 4.0. I am by far an expert in all things PV so if I am wrong on the ranges people are free to correct me.

The type of atty or carto you use will govern the ohms reading you get.

Hope this helps.

Jag

 

[Vidi]

Yeah I did the Zero thing. Touched the posts together and got .5 reading.

So , after compensating for that, my 1.5 LRs are mostly reading 1.9-3.0. I did have a couple of them reach the 4 range.

But three of them read ( after subtracting the .5 ) between 1.0 and 1.2.


Should those attys be tossed out then?

 

[Jaguar G]

What kind of device are you using?

A 1.0 - 1.2 ohm atty on a big battery would be okay to use, but it will give you some hot vapor. If the juice can handle it then it would be okay. If it is a mini style battery I would be concerned about frying the battery and not use it. I would not recommend LR on a small 510 or KR808 just because of the stress placed on the small batteries. Over 1000 mAh could handle it, anything less I would pass.

Also, are you buying one type of atty or carto from the same vendor and getting all these readings; 1.9-3.0 ohms? If so I think I'd look for a more consistent supplier. I use standard 510 attys and recently purchased 20 in a bulk pack, I checked them and all read 2.2 - 2.3.

Jag

 

[Stosh]

+ 1 on what Jaguar said....depends on what you're putting them onto.
Even a big battery mod 1 ohm is quite low, and will draw a lot of amps
even at 3.7v. Over stressing a battery can cause a catastrophic failure,
wouldn't want that near my face.

Not sure what you were paying, but for me a new atty costs less than a single
pack of smokes, well worth the cost.

 

[Vidi]

I'm using 900-1000 ego batteries.

I will be upgrading to the ProVari after XMas. My kids before my addiction lol.


As far as vendor, I currently have three different types from two different vendors. The ones And they are varying ages. Some of them I've used for months. I still have about a dozen usable atties IF we include the low reading ones ( three of those ) so if I tossed them out it's not a big deal.

I've tried several different attys and I'm now buying the Bridgeless Cisco spec 1.5's from Avid Vaper. They're 9 bucks each but the 5 dollar ones I got from other places just didn't perform. I WAS buying the 1.5 Cisco specs that still had the bridge/wick intact but they have the hole in them whereas the Bridgeless is sealed on the battery side. That keeps the leaking to a minimum and that really seems to help.

 

[Jaguar G]

Yeah, I'd be hesitant to use an ego with such low resistance; 1.5 is about as low as I'd go.

On another note, try to measue when clean and dry. The juice may be throwing the reading off if measuring when wet. I don't know this for a fact, just a thought from 28 years in the electronics field. I have seen contaniments cause havoc with precision current devices.

Jag

 

[Stosh]

If that's the case, put the suspect attys in a "for emergencies only" box, put them to the side.
No sense in risking ruining a battery over one or two attys.

upgrading to the ProVari after XMas

-- that should take all the guesswork out of it ....

 

[Katya]

Here's a step-by-step tutorial (for digital multimiters):

1. Turn your multimeter on and select the lowest Ohms setting, usually 200Ω.
2. Look at the display; the left side of the screen should display number 1.
3. First, test the resistance of your leads. Touch to two leads together, firmly, and wait for numbers to stabilize. On the right side of the screen, you should see a number between 0.0 and 0.4, or so. This is the resistance of your leads. Remember that number.
4. Now, to test your atty. Position your carto firmly on your desk; you don't want it to slip and slide all over the place. Touch one lead to the hole in the center of the atty and the other lead to the threads. Again read the display after the numbers have stabilized.
5. Subtract the resistance of your leads (#3) from the resistance of your atty(#4). This is the resistance of your atomizer.

This process takes some getting used to. Steady hand helps. Just keep practicing and you'll figure it out.

 

[juicejunky]

The MOFSET will fry on an Ego battery if you use less than 1.0 with it. I've fried two that way. Some of my Cisco 306 1.5s would work their way down to that after a month or so, not sure why. Maybe dry burning?

Check you attys often if you use 1.5s.