EMF while Supercharging

[Barry]

DC current

That's like ATM machine - redundant acronym syndrome

 

[mongo]

That's like ATM machine - redundant acronym syndrome

But if we go pedantic on that, how do you describe voltage?

 

[Barry]

But if we go pedantic on that, how do you describe voltage?

240 volts AC. Not that there's anything wrong with that...

 

[mongo]

240 volts AC. Not that there's anything wrong with that...

So... open circuit has 240 V of alternating current?
I kid, but it explains Fluke meters using pictograms instead of TLAs as others have. (Beyond the multilingual aspect)
/end derail...

 

[kingjamez]

Resurrecting this thread...

The meter also has two low bands, one 50Hz-1KHz and the other 50Hz-10KHz. The low bands were OK in the front seat, but massively high in the back seat. I would not want anyone in the backseat while the car is charging. The cable was also putting out some intense fields while the car was charging.

That makes sense. You are seeing the high frequency coming off of the AC-DC Boost / Buck converter. It's a switching power supply and while well shielded, can still leak a bit.
-Jim

 

[wdolson]

DC current has no changing flux, so should not irradiate any EM radiation. This is probably what you're seeing.

Rectified AC direct current still varies, the current just flows in one direction, so it is technically DC. But because it changes, EM radiation is possible. In the discussion, there was no evidence whether superchargers used rectified AC or pure DC. It looks like pure DC from my measurements.

That makes sense. You are seeing the high frequency coming off of the AC-DC Boost / Buck converter. It's a switching power supply and while well shielded, can still leak a bit.
-Jim

I saw the same thing off the cable going into the car. What I'm probably seeing is the EM field coming off the relatively high AC current flowing down the cable. Though the charging equipment under the seat probably contributes too.

 

[mongo]

But because it changes, EM radiation is possible. In the discussion, there was no evidence whether superchargers used rectified AC or pure DC. It looks like pure DC from my measurements.

During supercharging, the cables are directly connected to the pack (via HVJB contactors) so any voltage ripple would be minimal. Current ripple could exist, but that would cause a lower charging efficiency, so it likely a low level (esp with multiple interleaved chargers in the cabinet).

 

[wdolson]

3 of the 4 waveforms in this diagram are considered DC because current only flows in one direction:
https://i.stack.imgur.com/LC3dA.png

Batteries produce a steady current, but not all AC->DC power supplies bother to rectify the output to a steady current.

 

[Silent Ludicrosy]

Um, no. What researchers? Safety/health issue due to exposure to high EMF have been completely debunked. When making claims like this, please post your references to peer reviewed journals that are not on the fringe.

I saw it on an episode of Better Call Saul. Does that count?

 

[RDoc]

There are several pear reviewed studies conclusively showing that aluminum (not tin foil) hats extending below a meridian of the head touching the tips of the earlobes eliminates as much as 90% of the effect.

 

[JohnSnowNW]

There are several pear reviewed studies

 

[jomoGreener]

Someone told me this week that EMF can kill you and that Teslas are packed with it. I bought a meter (GQ EMF Radiation Detector) and have been testing the ins and outs of the claim. I measured inside and outside while parked. The meter showed the same value ranges as me walking around inside my house. 1.0mG to 4.0mG. I took the car for a ride and kept the meter on the seat between my legs as the person that made the claim said driving a Tesla would have an adverse effect on my .... I measured driving slow, fast, I stepped on it (M3P) and I pulled into a supercharger (40kW) and stayed in the car. No difference. Same numbers. The only time the meter would go higher and start beeping (DANGER!!) would be when I passed under or drove along power lines. I then read a few reports from various reputable organization on the dangers of EMF and have concluded (1) causation between exposure to EMF and cancer has not been established after 50 years of studies and testing (2) The EMF exposure in a Tesla when parked or while driving is the same as when you walk down the street. If the street has overhead powerlines you be exposed for longer than if you drive a Tesla down the same street. I also learned that inside the house the worst EMF measures came from my wife's hair dryer and a TP wi-fi extender. In retrospect I feel somewhat indifferent to the whole experience. I've started to expect that when articles are written on non-reputable sites containing negative information about problem A and that same site sells remedies for problem A on the same page that something fishy is going on. The person that made the claim is now on my full of *sugar* list.

 

[brucet999]

There are several pear reviewed studies conclusively showing that aluminum (not tin foil) hats extending below a meridian of the head touching the tips of the earlobes eliminates as much as 90% of the effect.

"There are several pear reviewed studies…"

Any apple reviewed, or peach reviewed studies?

 

[VT_EE]

Non-ionizing EMF has not been shown to be dangerous even after 50 years of studying it.

Electromagnetic Fields and Cancer

A fact sheet about research on electric and magnetic fields and studies examining their potential connection with cancer.

www.cancer.gov

 

[ucmndd]

In retrospect I feel somewhat indifferent to the whole experience.

That’s how I feel about this post.

Thanks for the 3+ year necropost bump, but there’s really no reason to type that much on this subject. It’s manufactured paranoia by the same set that told us microwave ovens were gonna kill us all 50 years ago.