Voltage drop on mech mod.

[HuskerCal]

So I pulled out my fish bone mech mod a week ago and just now measured for voltage drop through the mod on the contact point. At the moment my battery measures 4.05v and my mech measures at 4.05v. Btw this mod has served me well for the 40$ I paid for it at a B&M.

Was just wondering if anyone has a mod that measures out at 0v drop or am I measuring this incorrectly...note: I wanted to know the current coming through the 510 connection and did not measure through my vulcan rda.

 

[K_Tech]

Voltage drop is a function of current flow. Without an atomizer on your mech, there's no current, therefore no voltage drop, so you should see battery voltage.

This video talks about voltage drop, and the test rig used is really quite nicely done:

 

[Cullin Kin]

A true voltage drop test can only be done under load, i.e. with your rda on it. Without that, you are just testing the voltage on your battery.

I know mods with hybrid connections (4Nine, Stingray X) are pretty dern low when it comes to voltage drop.

 

[HuskerCal]

So im guessing I could get a rough number by simply measuring the posts on the rda while firing. Correct?

 

[K_Tech]

So im guessing I could get a rough number by simply measuring the posts on the rda while firing. Correct?

Yes, but only if you keep in mind that it is a very rough number.

Apologies for the somewhat long explanation, but:

Every battery, under load, will experience a drop in voltage. It's the nature of its properties. That voltage is being supplied by a chemical process, plus each battery has an internal resistance as well. The higher the load, (the more amps you're pulling out of the battery) the more its voltage will "sag".

So, the voltage that you will read at the atomizer will be the end result of your batteries voltage sag AND the internal resistance of the mod.

If you can keep the other parameters the same (charge state of the battery and resistance of the atomizer) the numbers become useful, but they still don't tell the whole story.

 

[Miata GT]

A true voltage drop test can only be done under load, i.e. with your rda on it. Without that, you are just testing the voltage on your battery.

I know mods with hybrid connections (4Nine, Stingray X) are pretty dern low when it comes to voltage drop.

Those perhaps but a good deal of the drop can come from the switch. If you have a mech with a switch that heats up under load it is being caused by resistance across the switch. This can be caused by a sub-optimal design or dirty contacts.

 

[bussdriver]

Seems to me like a test rig which utilizes a milli-ohmmeter or a micro-ohmmeter would be ideal.

Rather expensive (I sure am not going to buy one just for testing my mods), but it would measure the actual resistance of the mod/switch. Then the resulting ohms reading could be used to calculate the actual power loss in the mod relative to the particular build. Also could be charted to compare mods.

Battery voltage sag then would not be figured into the readings.

Any takers?

 

[K_Tech]

Those perhaps but a good deal of the drop can come from the switch. If you have a mech with a switch that heats up under load it is being caused by resistance across the switch. This can be caused by a sub-optimal design or dirty contacts.

I agree. Although there may be some losses in the threading of the mech, they're probably insignificant when compared to what is lost across the other contact points.

Seems to me like a test rig which utilizes a milli-ohmmeter or a micro-ohmmeter would be ideal.

Rather expensive (I sure am not going to buy one just for testing my mods), but it would measure the actual resistance of the mod/switch. Then the resulting ohms reading could be used to calculate the actual power loss in the mod relative to the particular build. Also could be charted to compare mods.

Battery voltage sag then would not be figured into the readings.

Any takers?

Check the video above. Since we're getting data on voltage and current, the resistance of the mech itself can be calculated, which is sort of the way a micro-ohm meter works.