[WireNut]

 If I remove the 2 conductor zip cord mains power cord on my vintage equipment and install C14 IEC connectors in it's place how should
I connect the additional ground conductor to the component?
I have 4 vintage components in my system that I’m planning on installing the IEC’s.
I'll be using 3 wire with shield power cords after installing the IEC’s.

Thanks,
Steve

[FullRangeMan]

Dont do it, dont put IEC power connector, if the original cable is bad replace by a modern quality cable solded direct inside the circuit as the original cord.

Female IEC power connectors will just add more connections and joints solders to the electric signal, its just one more part, a trick manufacturers created to facilitate use of expensive power cords.

[Speedskater]

Yes:
Don't do it.

[Elizabeth]

I disagree with the other two answers.
As for the ground? NO, do not connect the ground to equipment which never had one.
Leave the ground in the chassis IEC not connected.

Adding an IEC to a piece of vintage equipment is a nice touch.
Allows one to try other power cords.
(Which to me is a positive. The added connection of the new IEC is not a problem.)

The hardest thing is cutting the hole in the chassis. I have wanted to do this to several items I own, but the difficulty of cutting the hole stops me.

[*Scotty*]

If you do this, pay strict attention to how the hot and neutral are connected to the IEC inlet. Assuming that the existing power cord is properly wired, then the fuse is inline with the hot lead and in the event that a fault causes the the fuse to blow, the hot is disconnected from the equipment. If the hot and neutral leads are reversed the fuse can blow and the equipment will still be connected to the hot lead which is potentially a very dangerous situation.
 As far connecting the ground goes, I agree with Elizabeth on this, don't establish a ground connection where none has existed before on the gear. This avoids creating the potential for a nasty ground loop problem.
Scotty

[charmerci]

I would say - it depends on the equipment. Sometimes leaving the original - if suitably functional - is better for long term value.


How many completely original Camaros or Dodge Chargers, etc. are left? Very few and they command very high prices because most of them were modified and souped up by teens that wanted to show off.

[Elizabeth]

If you do this, pay strict attention to how the hot and neutral are connected to the IEC inlet. Assuming that the existing power cord is properly wired, then the fuse is inline with the hot lead and in the event that a fault causes the the fuse to blow, the hot is disconnected from the equipment. If the hot and neutral leads are reversed the fuse can blow and the equipment will still be connected to the hot lead which is potentially a very dangerous situation.
 

Agree. yes this is an important point. The hot lead should be carefully checked and the new hot plug pin matches the old hot wire (as mentioned, if it was properly connected)

[WireNut]

Agree. yes this is an important point. The hot lead should be carefully checked and the new hot plug pin matches the old hot wire (as mentioned, if it was properly connected)

Right, I have already checked all of my components for correct polarity with my DMM and all the cable plugs have been marked for correct orientation.
It's enlightening to see the difference in voltage readings for every piece of equipment with the plugs oriented one way and then rotated 180.
As a matter of fact, (say I have a disease ) but I've documented all of the results in a text file so I can review them at a later date if I have any doubts .

I totally agree with hard wiring new power cords to my components but it would be a PITA with the 7/16" thick cable I have in bulk. Smaller cables may be in order for this.
Also, I have enough IEC power cords now that just installing the C14 IEC's to my components would allow me to use my current
DIY cables. Bob Crump / Asylum mains cable.

Great advise here, Thank you all. I need to give this more thought. Everyone has good points on this  .

   
 
 

[*Scotty*]

Once you have determined the correct plug orientation for the lowest measured leakage voltage on the case, unsolder the transformer and reconnect it so that the transformer maintains this polarity when the fuse is in incoming hot lead to the power transformer.  This way you preserve your fuse protection and have the lowest voltage setting on the case for best sound. You may not have do anything or you may have to reverse the leads on the transformer.
 Also if you have made DIY power cords double check that the neutral and the hot from the wall receptacle are not inadvertently reversed at the IEC plug end. This is the only way to preserve the fuse protection which must located in the hot leg on the way to the power transformer.
 The nice thing about an IEC power cable is that hot and neutral cannot be reversed by changing the plug orientation at the wall receptacle. Once the correct polarity has been determined and the incoming power leads to the transformer soldered in the correct polarity, the piece of gear cannot be plugged into wall with the wrong polarity.
Scotty

[FullRangeMan]

Some vintage equip may be rare or expensive, it will no more be in original condition and loss resale value or sentimental value imo.

[dB Cooper]

Was there a problem (deterioration etc) with the original cable? "If it ain't broke, don't fix it."

[Speedskater]

The Hot lead needs to connect to the switch and fuse. Which may mean reversing the transformer wires for lowest leakage.

[WireNut]

Once you have determined the correct plug orientation for the lowest measured leakage voltage on the case, unsolder the transformer and reconnect it so that the transformer maintains this polarity when the fuse is in incoming hot lead to the power transformer.  This way you preserve your fuse protection and have the lowest voltage setting on the case for best sound. You may not have do anything or you may have to reverse the leads on the transformer.
 Also if you have made DIY power cords double check that the neutral and the hot from the wall receptacle are not inadvertently reversed at the IEC plug end. This is the only way to preserve the fuse protection which must located in the hot leg on the way to the power transformer.
 The nice thing about an IEC power cable is that hot and neutral cannot be reversed by changing the plug orientation at the wall receptacle. Once the correct polarity has been determined and the incoming power leads to the transformer soldered in the correct polarity, the piece of gear cannot be plugged into wall with the wrong polarity.
Scotty

Hi Scotty,

 Thanks for the great info. For correct polarity I've checked my wall outlets, DIY power cords, and all of my equipment for lowest measured leakage voltage which was a real eye opener especially on my turntable, preamp, and phono stage. All of my equipment is now plugged in with correct polarity. As for the transformers,switches and fuses, I'll change those if needed. Thanks.

[*Scotty*]

If you have reversed your AC plugs at the wall outlet you may have defeated the internal fuse protection. Reversing the plug polarity at the wall receptacle can place the fuse, which was inline on the hot leg of the incoming power, into the neutral leg headed back to the wall. If the fuse blows due a fault in the equipment, the blown fuse, in the now neutral leg leaves the incoming hot leg still connected, which can leave a lethal 120v setting on the chassis looking for somewhere to go, namely YOU .
Scotty

[WireNut]

If you have reversed your AC plugs at the wall outlet you may have defeated the internal fuse protection. Reversing the plug polarity at the wall receptacle can place the fuse, which was inline on the hot leg of the incoming power, into the neutral leg headed back to the wall. If the fuse blows due a fault in the equipment, the blown fuse, in the now neutral leg leaves the incoming hot leg still connected, which can leave a lethal 120v setting on the chassis looking for somewhere to go, namely YOU .
Scotty

 Scotty.

Thanks for the heads up. 
The original component plugs were not polarized so I marked them based on the voltage readings from my DMM.
The turntable was an eyeopener. Voltage was detected in the tonearm with the plug oriented one way and no voltage detected when the plug was reversed.
Same with my preamp. Low voltage one way, HIGH voltage with plug reversed.
Same thing with my phono stage. Now every component is marked.
I'll look into the way the fuses and transformers are wired.

Steve.