Electrical cord wrapped in a circle cause problems?

[Winged_One]

Several weeks back was at a private campground. The owner and another fellow were trying to work out a lack of ground on their 50 amp connection (this really is neither here nor there).

Anyway, the owner (a man in his 70/80's) said that having my 50 amp cord wrapped in a circle (you know, like a snake curled up), can cause electrical issues (feedback, etc).

Hey, I am no electrician.

Any reason we shouldn't wrap our electrical cords, or is it an old wives tale?

Or was it an issue way back, but with better insulation in the cords, not an issue anymore?

[jmnoeth]

Bottom line, coiling the cord should not cause any problems, unless you have some pretty extreme conditions.

Heating of the cord could be a problem, if the ambient temperature around the cord is significantly high, and the current draw through the cord is also high. But, under normal circumstances it should not be a problem. As mentioned in other posts, from a theoretical perspective, the inductive reactance of a coiled cord versus one that is not coiled would cause some losses. But, at 60hz (normal power line frequency), these losses would require very sensitive equipment just to measure them. Actually, the inductive reactance would more than likely be offset by the capacitive reactance of the conductors in the cord that essentially run parallel to each other.

[bucky]

Wait a minute, we are all wrong. Since the coiled cord had AC it could not have caused a fire from heat. Only a DC coiled cord can start a fire. I'm sorry that I missed this earlier.

[gkainz]

so that really WAS rocket surgery!!! 🙂

[pnichols]

You guys are good.

It was galvanic reaction between two pins of one of the connectors on one end. As I slowly withdrew one of the pins causing it, the voltage between it and one of the adjoining pins slowly declined. This fiasco held up a $$$$ rocket engine test until I found it and had the crew replace the missile instrumentation cable before proceeding with the countdown!

[enblethen]

pnichols;
Sounds like that may have been a chunk of composite missile cable.
Induction from almost any of electrical inside some of the facilities will be measureable.

[westend]

pnichols wrote:
I'm way at the end of this, but I'll add one more true-story mystery to see who can solve it -

While In the AF at a high tech facility I once held a multi-wire cable in my hands not coiled - with each end laying on the floor - and there was a voltage we measured across a couple of pins of the connectors on each end. What caused this?

Hint: I had to destroy this expensive taxpayer provided cable to solve it.

Capacitance in the wires, induction, or galvanic reaction between wires?

[pnichols]

I'm way at the end of this, but I'll add one more true-story mystery to see who can solve it -

While In the AF at a high tech facility I once held a multi-wire cable in my hands not coiled - with each end laying on the floor - and there was a voltage we measured across a couple of pins of the connectors on each end. What caused this?

Hint: I had to destroy this expensive taxpayer provided cable to solve it.

[D_E_Bishop]

This has been very informative. I never fully understood theory of drift or EMF and Counter EMF and while I still don't I now understand the theory of the pain in my side being directly proportional to the creative humor of a bunch of guys who like to extrapolate and confuseigate (I just made that word up) a truly important issue that had been logically answered in plain English.

Thanks to the Mods on this page for letting the thread go on forever or at least until the tears in my eyes made me quit reading.

It has been fun.

[Ductape]

This should be a sticky!

Can someone explain which connections to swap so my solar panels can be used as scare lights at night? Does that only work with MPPT?

[Hiking_Hunter]

smkettner wrote:
Must have been an improvement over the retroencabulator....

Yeah, that's a classic.
The remake may be even better!

[Hiking_Hunter]

gkainz wrote:
Since it's AC in the cord, the reverse current cancels out the centrifigal force with centripal force and net is zero. However, if neutral bleeds over to ground, then the power company starts sucking the reserve elecricity out of your components, whereas your toaster converts toast into fresh bread, coffee makers turn coffee into fresh water and your freezer makes hot water.

OK, that explains something that happened to me a couple of months ago. When I installed a new battery in my truck the cables were too long. Instead of cutting them, I coiled them in a very tight coil to take up the slack. This must have introduced some centripal force, which changed the alternator into a motor. Instead of generating electricity to charge the batteries, it started turning the crankshaft. The engine started sucking the particulate matter out of my DPF, combining it with oxygen and creating diesel fuel. It was really a problem. After 100 miles or so, I had fuel running out of my filler cap all down the side of the truck. I've had to wash it three times in the last week.

I'll take the coils out of the cable first chance I get.

[Horizon170]

westend wrote:

Do what you want but an electric cord wrapped in a circle is an electromagnet less an iron core. It creates and electromagnetic field and reduces the power at the business end.

What difference in power have you noticed when a cord is rolled?

Don't know, I'm smart enough to remember what I was taught when I worked on Nike Hercules Missile systems for the U.S. Army.
If you have a monster cord and a light load you will not notice, but subject that same cord to the maximum load an watch stuff start smoking and melting.
Marvin
PS, MEX or DRWIZ, clear up this mess so we novices can rest. 🙂

[time2roll]

Hiking Hunter wrote:
This circuit is known as a quasi-complimentary symmetery, chopped transient blanking astable multivibrator (with regenerative feedback) circuit.

Must have been an improvement over the retroencabulator.... (google that)

[2oldman]

🙂 :):):):):):):):):):)