Re: Isolation transformer questions
May 2nd, 2020, 8:28 pm
Pelliott321 wrote:the ground is not isolated all grounds on all sockets are grounded to the chassis
there is a green/yellow wire coming from the tranny that is not shown on the schematic. I assumed that it should be grounded also
The question I have is does the third pin on the power plug you plug into the wall socket carry through to the ground bond in your home's electrical distribution system.
That's assuming there is a third wire ground bond -- your house is over 50-years-old and ground bonds were not even a pipe dream then. Was your house wiring completely up-graded to modern codes or only partially?
My previous house was built in 1935 and wired with two-conductor armored-cable known as BX cable. No ground bond.
Re: Isolation transformer questions
May 2nd, 2020, 9:05 pm
In the first photo you can see the house mains side with ground going over to the chassis ground, as well as each load side sockets grounds going over to the chassis ground.
Is this wrong
Is this wrong
Re: Isolation transformer questions
May 2nd, 2020, 9:27 pm
Pelliott321 wrote:In the first photo you can see the house mains side with ground going over to the chassis ground, as well as each load side sockets grounds going over to the chassis ground.
Is this wrong
OK. I see that the transformer-casing ground bond is passed through to the IEC outlet. That brings me back to the question as to how your house is wired. My experiences with vintage residential electrical upgrades was that old-style fuse panels were replaced with circuit-breaker panel-boards and some easily accessible wiring upgraded to 2-conductor ROMEX with a 3rd ground bond wire. However, for the most part the bulk of the "buried" vintage wiring was left untouched even though modern receptacles were installed that have that third pin, the ground bond. In that case the 3rd pin is not wired to anything - or - maybe tied to the BX armor which is a major NO-NO.
Re: Isolation transformer questions
May 3rd, 2020, 7:31 am
I rewired my sound room with 10 gauge two conductor plus ground two years ago, All mains sockets are new and hospital grade. House grounds were refreshed and all connections checked.
Re: Isolation transformer questions
May 3rd, 2020, 9:30 am
Pelliott321 wrote:I rewired my sound room with 10 gauge two conductor plus ground two years ago, All mains sockets are new and hospital grade. House grounds were refreshed and all connections checked.
That said -- does the isolation transformer work as advertised even though you got those "funny" readings? Or - are you experiencing a problem and trying to trouble-shoot it?
Re: Isolation transformer questions
May 3rd, 2020, 9:36 am
it runs anything i plug into it
but when i tested it with the circuit tester and got an open ground indication i started to question things
the test shows good on all other sockets i test.
but when i tested it with the circuit tester and got an open ground indication i started to question things
the test shows good on all other sockets i test.
Re: Isolation transformer questions
May 3rd, 2020, 9:42 am
Pelliott321 wrote:it runs anything i plug into it
but when i tested it with the circuit tester and got an open ground indication i started to question things
the test shows good on all other sockets i test.
Stu? Any thoughts?
Re: Isolation transformer questions
May 3rd, 2020, 9:50 am
The load side (receptacle) grounds should be internally hard wire connected to the neutral connection. Since you have a dual secondary transformer, the neutral connection can be the center tap, if the windings are series connected, or, if the windings are paralleled, then it would be one of the transformer leads (lead pair) tha TV is connected to ground.
Possibly this is why it is open. You need to make the correct connection based on how the output is wired.
This is a separately derived system. Making the ground connection from your receptacles to the secondary of the transformer is critical for noise and safety. It is the ground path that will complete the circuit if a live wire comes into contact with a metal surface, causing excess current to flow which, in turn, trips the circuit breaker or blows a fuse.
One word of caution. do not connect any portion of your stereo to a power source not connected to the transformer. The results can be catastrophic
Possibly this is why it is open. You need to make the correct connection based on how the output is wired.
This is a separately derived system. Making the ground connection from your receptacles to the secondary of the transformer is critical for noise and safety. It is the ground path that will complete the circuit if a live wire comes into contact with a metal surface, causing excess current to flow which, in turn, trips the circuit breaker or blows a fuse.
One word of caution. do not connect any portion of your stereo to a power source not connected to the transformer. The results can be catastrophic
Re: Isolation transformer questions
May 3rd, 2020, 10:24 am
Later today I'll draw out what I wired and draw out what I think Stuart is saying
Listening to Bill Cole on Wpfw a Sunday morning ritual
Listening to Bill Cole on Wpfw a Sunday morning ritual
Re: Isolation transformer questions
May 3rd, 2020, 4:19 pm
Tom Cole.
A great show as usual.
I'll be curious of your impression of how your system sounds with that installed. I've not heard one installed that sounded better compared to without. Many seem to suck the life out of the music. I haven't compared a regenerator yet.
A great show as usual. I'll be curious of your impression of how your system sounds with that installed. I've not heard one installed that sounded better compared to without. Many seem to suck the life out of the music. I haven't compared a regenerator yet.