Directional wires/cables

I believe that is more in lines with roughing in the electrical to the rooms, but more in line with this thread, I am curious if were able to see the power cords connecting those machines; any directionality on them?

Nope...

I wouldn’t even bring up wire directionality to a fellow electrician. Or how electrical energy, power, actually travels from an AC source to a connected load. They would look at me like I was nuts... To the average electrician AC current flows back and forth in a closed electrical circuit. E = I x R... P = E x I. They measure current with a Clamp Amp meter. Current does the work... Current makes the filament in the light bulb light.

I am not saying all Journey wireman electricians today are of the same mind set.

Especially Master Electricians.

I don’t know if you are aware, but Shunyata claims to have some of its power cables in some hospitals as the filters and shielding reduce noise on the heart monitors and enable the doctors to better read the data from them. Not sure if any have made their way to MRI’s etc.

I remember reading that too. To be honest with you I never looked at any of the power cords used in a hospital.

(FWIW, I never considered the wire in a 120Vac power cord was directional. You can’t really check for yourself. It comes with a male and female connector. Now an interconnect, what signal voltage are we dealing with? Maybe around 2V, usually less sometimes?)

I can tell you any power cord used in a patient care area are UL Listed hospital grade and have Hospital Grade connectors. Who was in charge to made sure they were? It was either Bio Med or Bio Tech. Every receptacle outlet in patient care rooms, ER, OR, ICU CCU, Cath Labs, others I can’t think of, were inspected by either Bio med or Bio Tech, (can’t remember which one), for any exterior damage and checked the equipment ground contact of the outlet for a minimum of 4 ounces of contact pull out holding contact pressure. They had a device they plugged into the outlet that had a mechanical pointer that indicated the pulling out resistance in ounces. I can’t remember how often they tested the outlets. But I bet they checked power cords as well when checking the wall outlets, to make sure they were UL Listed Hospital Grade, and checked for any signs of damage.

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One thing I do remember. The shop, the electrical Contractor I worked for, shop Branch Manager, without consulting me first, gave the hospital a price to change out all the 20A duplex wall outlets in patient rooms on two floors of a wing in the hospital. It was a competitive bid job, Therein bidding against another Electrical Contractor. Well he was the low bidder. He got the job. Problem? For the hospital grade duplex wall outlets, an electrical wholesale house salesman gave him great price on a bulk order of Pass & Seymour 20A 8300 hospital grade duplex receptacle outlets. At the time I was ordering, using, a good quality Leviton 8300 hospitable grade duplex receptacle outlets. They held up good compared, against, the high dollar 20A Hubbell 8300 outlets.

You just just don’t change the manufacturer of a hospital grade electrical outlet used in a hospital. Not that hospital anyway. I got the in house electrical department shop foreman to consider the Leviton 8300 outlet. I gave him a couple and told him to physically abuse the hell out of them. Let me know what he thought of them. He got back with me and gave me approval to use them instead of the high dollar Hubbell 8300 outlets.

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Cut to the case, my boss said that’s what he bid that’s what will be installed. Fine!

So I had my electricians install the P&S outlets. LOL, you just don’t walk into a patient room, that has a patient in it, and change out wall outlets. You talk to the floor nurse manager, Very nicely, and say "I have been hired to change out all the wall outlets in patient rooms on the floor." "Would you please call me on my cell phone and let me know when a room, or maybe rooms, are empty and available."

She might say something like, "Yeah, I heard they had to be replaced."

Next thing out her mouth, "How long will you tie up my patient bed,.. the room?" Get an idea what you are dealing with? A lot of wasted non productive time. Time Is Money!

About a year later I got a call from Bio-med or Bio tech asking me if I installed new outlets on two floors in the so, so, wing. LOL, they knew I did... Next words out of the guys mouth we started testing the outlets on one of the floors and outlets are failing the test.

Not B.S. They explain it if you’d just read the instructions. Worlds Best Cables simply say this: These Quad RCA cables are configured as directional cables, we strongly believe that this is the most appropriate topology for best performance and superior noise rejection characteristics. Most cable assemblers will either leave the shield floating at both ends or grounded at both ends which makes it easier to assemble but inferior in performance. We do not take such shortcuts.

What does "Directional" mean: This simply refers to the construction, which is depicted in their included diagram, which shows the shield, which is connected to the ground at the signal emitting end acts as a Faraday cage which rejects external noise that could degrade the signal. The cable will work even if you connect it the wrong way, but this will diminish the noise rejection capabilities of the cable.

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I work with several electrical engineers and they concur with the above. Does it make any "real world" difference? That will depend on the electrical environment of your equipment and how "noisy" it is. But it doesn’t hurt to be erring on the side of reducing possible interference. I mean, short of using balanced cables for every single interconnect (something not possible on most devices), using cables that are "directional" seems to be the next best thing.

@jea48 

Did you do your practical hospital wiring based on the "false" teachings from your apprenticeship, or based on what you learned here?  Be honest.

Maybe you were the sparkie that "forgot" to connect The Canberra Hospital's UPS to the mains supply?

Perhaps you could restate your understanding of electrical energy, as set out below, so it makes sense?  You might care to include the effects of resistance and voltage ... and the relationship between power and energy:

Energy is what makes the light bulb light, not the current. Current is not consumed by the load. Proof, it returns to the source. Current measures the same on both sides of the load.

@jea48 

You seem to accept that

Light is the fastest-moving stuff in our universe. It travels at 186,000 miles per second (300,000 km/sec)

I'd add "in a vacuum" just for completeness.

You would, I hope, agree that low frequency electromagnetic waves are radio waves and travel at the speed of light.

So would you dispute that the wavelength of 60-Hz radio waves in a vacuum is 186,000 / 60 or about 3,100 miles?  That's about the radius of our planet.

Do you really think the conductors in a circuit board radiate any detectable amount of 60-Hz radio waves?

You might care to read up on the difficulty of communicating with submerged submarines using extremely low frequency radio - see Communication with submarines - Wikipedia