Three prong vs two.

[quaddriver]

View attachment 1292094
The primary electrical system is the electrical system on the utility side of the transformer. ... When electrical current cannot flow through a neutral conductor, due to some type of damage or defect in the circuit, more current will use a path through the earth to return to the power supply.

The earth is not the normal neutral in the grid.

was at the beach for the weekend but this is late, however consider something...

recall the question asked day 1 of class, the true or false (see previous post)

At your service entrance the neutral of the 220 is derived from the center tap of your transformer, and the 1.5kv (or most likely more) is the result of many step down transformers from the actual power plant.

AS power leaves the plant, each circuit is stepped in voltage based on the load capacity of each branch and the voltage reduced. we all know kirchoffs and ohms laws and there are fancy charts to show us conductor sizes for various currents. but there is this other law called the catenary law that lets us derive the forces on a hanging wire and it tells us when the forces generated by the weight of the wire overcome its breaking point. To carry the power or a village at 220v, the wire might 6 inches thick and it will break, so someone, somewhere, sometime ago did the math and figured if they up the voltage - drastically - then less current has to flow and hence a lighter (smaller) wire may be used.

The point of the history/physics lesson is, many many step downs occur, from the power plant to your house and at each point of step down, neutral is redefined. since wire has resistance, you end up with a floating neutral to even a delta power concept sooooo, what do they do...

they ground to earth every single neutral connection, outside of a building, no matter how many or where they occur.

as I said before, on the pole, the top contains the hot/live wire. the lower wire contains the neutral which is ALSO the ground and this is reinforced every so many feet along the path. hundreds of times? thousands of times?

If current is indeed following EVERY path to ground, how many connections start to make a real difference?

I assure you, if penelec lets you do testing you will find that at the source connections of every step down, the current going 'out' on the hot wire far exceeds the current coming 'back' on the neutral wire, the balance going thru worms and stuff. It has to, It has no choice.

ETA: corrosion and degradation of the wires...all of them, occur at a fairly static rate. There can and does come a point where the overhead wires fail as the current approaches the limit of the wire left but does not exceed the fusing. unless something hits something and its a mechanical failure, its always (99.9%) the hot side that drops...

 

[WaynerN]

Who are you telling this too? BTW, I have my Ugly's book right here.

Also the design voltage is 240, not 220. I hate it when people call it 220 'cause that is not the design standard.

I don't think anyone said the neutral wasn't grounded, it was said that it is not the normal current carrier, nor the designed carrier of current as you suggested in a previous post.

 

[Zygmo]

Ok....I just now opened the Marantz Tuner. Decided to just shorten the cord. As someone here said, the round third prong on the cords in this equipment is really just an indexer....to make sure the two blades are correctly connected. There is a forth, bare wire. This wire, along with the black and white insulated wires goes into screw posts. The bare wire is connected to chassis ground through the screw post. Very convenient and simple. I cut the cord down to about 12 inches....much better than a stiff bundled up 5 ft cord. Also, the through grommet size for the cord is controlled by two bolts and nuts. Will fit any size cord. This tuner and integrated amp is very clean and nicely laid out inside. A lot of wire wrap. The tuning cord is still tight. No swollen or leaking caps.
Now, on to shorten the cord on the integrated amp.

 

[biscuithead]

Ok....I just now opened the Marantz Tuner. Decided to just shorten the cord. As someone here said, the round third prong on the cords in this equipment is really just an indexer....to make sure the two blades are correctly connected. There is a forth, bare wire. This wire, along with the black and white insulated wires goes into screw posts. The bare wire is connected to chassis ground through the screw post. Very convenient and simple. I cut the cord down to about 12 inches....much better than a stiff bundled up 5 ft cord. Also, the through grommet size for the cord is controlled by two bolts and nuts. Will fit any size cord. This tuner and integrated amp is very clean and nicely laid out inside. A lot of wire wrap. The tuning cord is still tight. No swollen or leaking caps.
Now, on to shorten the cord on the integrated amp.

Nice. Finally back to original thread.
Are you saying that you have four wires coming from the power cord into the unit? If you do, I've never seen that... hmm.
Does it look like the ground wire is OEM, or does it look added? Did someone already do the research and mention that the 2020 did not have a ground? Are these US units? Apologies if this has already been addressed...

 

[Zygmo]

Nice. Finally back to original thread.
Are you saying that you have four wires coming from the power cord into the unit? If you do, I've never seen that... hmm.
Does it look like the ground wire is OEM, or does it look added? Did someone already do the research and mention that the 2020 did not have a ground? Are these US units? Apologies if this has already been addressed...

Judging from the way the original weird cord setup was, Biscuithead, I assume they made the actual stereo component cord universal, and just supplied the box that those cords plugged into to fit the country power system that each was shipped to.

I put these cords on years ago...and I am sure I wired them up to the inside the way the original cords were. The Green wire was cut off, and the bare wire went to chassis.
I have no idea where I got these cords, because I don't remember ever seeing 4 conductor, three prong wires either. These have the tough (nylon?) strands surrounding everything, with a twisted bare wire and three insulated conductors...white, black and green. I have reassembled the tuner, so I can't take a picture of it, but I will do the integrated amp now, and will take a picture of the wiring inside if you would like.

 

[biscuithead]

Judging from the way the original weird cord setup was, Biscuithead, I assume they made the actual stereo component cord universal, and just supplied the box that those cords plugged into to fit the country power system that each was shipped to.

I put these cords on years ago...and I am sure I wired them up to the inside the way the original cords were. The Green wire was cut off, and the bare wire went to chassis.
I have no idea where I got these cords, because I don't remember ever seeing 4 conductor, three prong wires either. These have the tough (nylon?) strands surrounding everything, with a twisted bare wire and three insulated conductors...white, black and green. I have reassembled the tuner, so I can't take a picture of it, but I will do the integrated amp now, and will take a picture of the wiring inside if you would like.

It sounds like a type of "S-O" cord. This is the industry term for a commercial grade multi-conductor cord designed for hard usage. Does the outer jacket have any identifying writing on it ?
I'm sure you'll be fine, but this era of Marantz rarely used an equipment ground. If you haven't experienced an audible hum, then carry on.

 

[vwestlife]

Also the design voltage is 240, not 220. I hate it when people call it 220 'cause that is not the design standard.

Calling it 110 and 220 when it's actually 120 and 240 volts is electricians' lingo. The old-timers teach the new apprentices, who then go on to teach the next generation, etc., and they just never bothered to update their terminology. Just like how many people still refer to a circuit breaker panel as a "fuse box".

 

[Zygmo]

It sounds like a type of "S-O" cord. This is the industry term for a commercial grade multi-conductor cord designed for hard usage. Does the outer jacket have any identifying writing on it ?
I'm sure you'll be fine, but this era of Marantz rarely used an equipment ground. If you haven't experienced an audible hum, then carry on.

Yes.SVT Shielded E55178 AWG18X3C VW-1 75 C CWCO. It certainly is a heavy duty cord. I just finished changing the Amp's cord length. Setup inside just like the tuner was. There is no hum...everything sounds fine and looks much better now.

Thanks.
Dean

 

[biscuithead]

Yes.SVT Shielded E55178 AWG18X3C VW-1 75 C CWCO. It certainly is a heavy duty cord. I just finished changing the Amp's cord length. Setup inside just like the tuner was. There is no hum...everything sounds fine and looks much better now.

Thanks.
Dean

Ok. The "shield" is the uninsulated wire, the green is ground. You say green is clipped, and isolated. Shield is made to chassis. I suspect the shield on the plug side doesn't bond to ground prong, so you probably aren't grounded, thusly no hum. ... or it is bonded and it isn't creating a hum... no matter. You could always do a continuity test to see.

This type of power cord is usually used on test equipment.

Let's see if we can break down those numbers on the cord , so future thread readers know what they mean:
SVT = manufacturer
E55178 =MPN = manufacturer part number
AWG-18 = 18 gauge wire
X3C = three conductors

Shielded = a wire that usually accompanies a foil that completely surrounds the insulated conductors, it shields RF and inductance. It isn't counted as a conductor, therefore the wire is three conductor plus shield.

VW-1 = ? Maybe amperage rating ?
75 C = temperature rating
CWCO= ? Maybe capacitance


* this is probably all more info than necessary, but it should be mentioned that a lot of knowledge, consideration and engineering is involved in choosing just a power cord for your equipment . If you are going to change/alter a power cord, you should know what you're doing.

@Zygmo, you should be fine.

 

[Old-School]

Ok....I just now opened the Marantz Tuner. Decided to just shorten the cord. As someone here said, the round third prong on the cords in this equipment is really just an indexer....to make sure the two blades are correctly connected. There is a forth, bare wire. This wire, along with the black and white insulated wires goes into screw posts. The bare wire is connected to chassis ground through the screw post. Very convenient and simple. I cut the cord down to about 12 inches....much better than a stiff bundled up 5 ft cord. Also, the through grommet size for the cord is controlled by two bolts and nuts. Will fit any size cord. This tuner and integrated amp is very clean and nicely laid out inside. A lot of wire wrap. The tuning cord is still tight. No swollen or leaking caps.
Now, on to shorten the cord on the integrated amp.

LOL

While everyone was having a pissing match the OP opened the equipment, and connected a new cord! Priceless. @biscuithead has the most real world explanation of the reason. Simple. To keep the polarity straight. That way multiple devices on one circuit dont cause a short IF the hot and neutral are connected somehow. You can make it (or anything) as complicated as you want. The simple truth is there are only 2 wires. Follow those 3 wires back to your circuit box and see where they go. Yep neutral and ground are one and the same for 120. Each leg of the incoming 240 referenced to ground is 120. Dont need to get out a slide rule to figure that out!

You could always just put a power strip on the inside or back of that cabinet and do away with what ever proprietary plugs were in there. Sounds like way more trouble than they could ever be worth.

 

[quaddriver]

Who are you telling this too? BTW, I have my Ugly's book right here.

Also the design voltage is 240, not 220. I hate it when people call it 220 'cause that is not the design standard.

I don't think anyone said the neutral wasn't grounded, it was said that it is not the normal current carrier, nor the designed carrier of current as you suggested in a previous post.

IF this post is to me, I never once said those words in any post, explicitly or implicitly.

 

[WaynerN]

It sounds like a type of "S-O" cord. This is the industry term for a commercial grade multi-conductor cord designed for hard usage. Does the outer jacket have any identifying writing on it ?
I'm sure you'll be fine, but this era of Marantz rarely used an equipment ground. If you haven't experienced an audible hum, then carry on.

"S" is for 600 volt, "O" is for the category of "oil resistant".

Putting a polarized plug on vintage equipment is OK, but I would not put a ground wire on them (not designed for it, not needed). The line (the narrow blade) should go to the fuse and switch. The neutral (the wide blade) should never be switched (or fused).

Back to cord codes, cords that start with "J" would be just fine (300 volt) and most of them end up with a "T", which stands for "thermoplastic".

 

[biscuithead]

"S" is for 600 volt, "O" is for the category of "oil resistant".

Putting a polarized plug on vintage equipment is OK, but I would not put a ground wire on them (not designed for it, not needed). The line (the narrow blade) should go to the fuse and switch. The neutral (the wide blade) should never be switched (or fused).

Back to cord codes, cords that start with "J" would be just fine (300 volt) and most of them end up with a "T", which stands for "thermoplastic".

Yes thank you... did you keep reading where the op posted what the writing on the cord said... it was a cord probably originally designed for test equipment with shield. I don't know if your intention is to sound contentious, but I question the spirit of your responses. Let's just all work together to give the op an answer and the best info. It's not a " I know more than you " competition, this is an audio community that is supposed to help those that ask.

You're correct about the s-o cord. Sometimes industry terms are not precise... but those in the industry know this is a given. It's good to define this for those that don't know.

 

[WaynerN]

Yes thank you... did you keep reading where the op posted what the writing on the cord said... it was a cord probably originally designed for test equipment with shield. I don't know if your intention is to sound contentious, but I question the spirit of your responses. Let's just all work together to give the op an answer and the best info. It's not a " I know more than you " competition, this is an audio community that is supposed to help those that ask.

You're correct about the s-o cord. Sometimes industry terms are not precise... but those in the industry know this is a given. It's good to define this for those that don't know.

I never try to be contentious, but sometimes people think my responses are. I am about facts. I have many years in the electrical business, so there is no spirit of "superiority", rather facts. The OP has been given the answer several times, but chooses to ignore the answer(s).

 

[Zygmo]

I never try to be contentious, but sometimes people think my responses are. I am about facts. I have many years in the electrical business, so there is no spirit of "superiority", rather facts. The OP has been given the answer several times, but chooses to ignore the answer(s).

I chose to ignore the answers?? LOL Which ones? Why do you think I went ahead and made the choice that suited me (and, I believe, the equipment) best. Assuming I wired it up the first time resembling the original way, I then I wired it up again with shorter wires, but still kept the original, 3 wire setup inside the components. And through all this, the stereo sounds fine, with no hum. I'm listening to it right now.

I actually did exactly what one person here said.....just cut the cords shorter, and reassemble the wires inside back the way they were. Biscuithead, for instance, said what I did should be just fine. Just guessing here....I would say I did about what half of the respondents recommended (anyway, the one's that stayed on the original thread.)

 

[Zygmo]

LOL

While everyone was having a pissing match the OP opened the equipment, and connected a new cord! Priceless. @biscuithead has the most real world explanation of the reason. Simple. To keep the polarity straight. That way multiple devices on one circuit dont cause a short IF the hot and neutral are connected somehow. You can make it (or anything) as complicated as you want. The simple truth is there are only 2 wires. Follow those 3 wires back to your circuit box and see where they go. Yep neutral and ground are one and the same for 120. Each leg of the incoming 240 referenced to ground is 120. Dont need to get out a slide rule to figure that out!

You could always just put a power strip on the inside or back of that cabinet and do away with what ever proprietary plugs were in there. Sounds like way more trouble than they could ever be worth.

BTW, Old-School, I did not connect new cords. I shortened the cords that were on them, and reattached them exactly the way they originally were. Also, I do have a power strip attached to the inside back of the equipment, and all I wanted to do was eliminate the two big bundles of heavy cord cluttering up the back. So I did it the surest and safest way.

 

[biscuithead]

I never try to be contentious, but sometimes people think my responses are. I am about facts. I have many years in the electrical business, so there is no spirit of "superiority", rather facts. The OP has been given the answer several times, but chooses to ignore the answer(s).

Forgive me... but from what I have witnessed, you are not about facts. You present a reality of your own, very faintly resembling a rewrite of this thread, then engage in an opinion opposing this alternate reality. I've been married long enough to recognize this tactic... you, my friend are nothing more than a wife !

 

[WaynerN]

Really? That is why I retired at age 55 with a basket full of goodies, and debt free.

 

[biscuithead]

Really? That is why I retired at age 55 with a basket full of goodies, and debt free.

What a coincidence, so did my wife!
... but at age 25

 

[Old-School]

BTW, Old-School, I did not connect new cords. I shortened the cords that were on them, and reattached them exactly the way they originally were. Also, I do have a power strip attached to the inside back of the equipment, and all I wanted to do was eliminate the two big bundles of heavy cord cluttering up the back. So I did it the surest and safest way.

Nice work. Sure and safe.