why balanced power last before component?

Atmasphere,

That is why NEC Code as well as UL requires the output of the balanced power system to be GFCI protected. Any imbalance of either hot conductor to ground will cause the GFCI to trip open. As little as 5 or 6 milliamps of ground fault current to ground will trip the GFCI open. Wonder how many guys here who wired their own balanced power systems are using a GFCI on the output of the transformer?

It should be noted that a GFCI will not operate as designed when connected to the output of an "Isolated Power System" (Floating above ground). An equipment ground is not needed for a GFCI to operate as designed, but it must be connected to a "Grounded AC Power system" to operate as designed.

Jea, technical verbage discrediting medical grade transformers is trivial here. When you're in hospital next then you can worry about them. :-) . Maybe invite Bill in to discuss the topic with you as well as he too obviously knows absolutely nothing about EQUITECH'S patents and products. "Shocking! ;-) ...(all tongue in cheek :-) But, I can't imagine what got into you and Atma; hope it passes.

Jea, technical verbage discrediting medical grade transformers is trivial here. When you're in hospital next then you can worry about them. :-) .
10-03-14: Ptss

Huh?

IF the transformer is indeed configured as an "Isolated Power System”, there in the output is floating above ground, the Isolated Power System is monitored by qualified personnel.
In hospitals Isolated Power Systems are used in ER Rooms, CATH Lab Rooms, OR Rooms, some X-ray rooms . Any place where electrical equipment or monitor equipment is connected to a patient.

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Maybe invite Bill in to discuss the topic with you as well as he too obviously knows absolutely nothing about EQUITECH'S patents and products. "Shocking! ;-)

I suggest you climb down off your high horse and read the “EQUITECH'S” fact sheet on where balanced power systems can be used. A balanced power system is not to be used in a residential occupancy.

You will actually get better isolation from the mains power if the primary winding of an isolation transformer is fed from the two Hot ungrounded legs of the main service power, there in US 240V, and the secondary of the transformer is configured for straight 120V out with one lead, leg, of the secondary winding earth connected making that lead the neutral, the Grounded Conductor. The user will then have a new 120V separately derived power system.
Note. Per NEC Code the earth connection shall be made at any point of the grounding electrode system of the main electrical service.

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...(all tongue in cheek :-) But, I can't imagine what got into you and Atma; hope it passes.
Ptss

Ignorance is bliss.
.
Jim

Actually, if a GFCI is installed, it does not need the ground circuit to operate correctly. So what is needed is exactly as the NEC requires: each outlet must be of the GFCI type.

If the installation does not have GFCI outlets for every component used, then there is a danger. But otherwise its OK as far as the user is concerned.

If there is a short in the equipment as I had proposed in my prior post, the GFCI outlet will still trip. So my safety concerns were the result of over-thinking this...

Actually, if a GFCI is installed, it does not need the ground circuit to operate correctly. So what is needed is exactly as the NEC requires: each outlet must be of the GFCI type.
10-03-14: Atmasphere

True, a GFCI does need to be connected to a circuit that has an equipment grounding conductor to operate as designed by the manufacture. NEC Code allows in the case of a two wire branch circuit with a two wire receptacle, the receptacle can be replaced with a GFCI receptacle. The GFCI receptacle will operate just fine.

The reason the GFCI works is because the two wire branch circuit is fed from a Grounded power system. The two wire branch circuit consists of one hot conductor and one grounded conductor, the neutral. If a three wire cord and plug piece of equipment is plugged into the GFCI receptacle and a ground fault occurs from the hot conductor to the metal case/enclosure of the equipment the GFCI will trip open when about 5 to 6 milliamps of ground fault leakage current is detected.

In the case of a two wire cord and plug connected appliance/equipment if the hot conductor comes in contact with the metal case/enclosure the case would be hot with respect to ground, a 120V nominal potential. If a person were to touch the Hot metal case/enclosure and come in contact with a grounded object current will flow through the body. If the current flow exceeds 5 to 6 milliamps the GFCI will trip open.

NOTE. A GFCI will not protect a person from a line to line, (Hot to neutral), contact.

You can see from my post above why a GFCI will not operate as designed when connected to an “Isolated Power System” where the secondary is floating above ground. The GFCI needs a reference to ground to operate.
Jim