by Tomi Engdahl on Thu May 04, 2006 2:46 pm
The results you got makes perfect sense.
The reason why you got the numbers like you have in your measurements lies in the way how the isolation transformer works and how you made the measurements.
The output of isolation transformer is a floating power source. There is no connection to the ground at all through anything. When you make one connection with your multimeter between the "phase" side of isolated source, you will not get any voltage because you are essentially measuring an open circuit consisting of your grounding wire - multimeter - floating 230V output - and open circuit here. No current floating, no measurable voltage withmultimeter. Same thing happens with "neutral" side.
The isolation works. Any single one connection from either side of the isolated output will give you 0V to multimeter.
If you have two identical multimeters, and connect one from "phase" to ground and other from "neutral" to ground, you would get reading of 115V on both of them. The sum of those is that 230V. In this case your measurement circuit would consist of loop consisting of follwoign parts: floating 230V power source - multimeter 1 - ground - multimeter 2 - other end od 230V power source
If your multimeters are not ideantical, then the voltages you get on them can be different, but the sum of measured voltages would be always 230V AC within your measurement accuracy.
The results you got makes perfect sense.
The reason why you got the numbers like you have in your measurements lies in the way how the isolation transformer works and how you made the measurements.
The output of isolation transformer is a floating power source. There is no connection to the ground at all through anything. When you make one connection with your multimeter between the "phase" side of isolated source, you will not get any voltage because you are essentially measuring an open circuit consisting of your grounding wire - multimeter - floating 230V output - and open circuit here. No current floating, no measurable voltage withmultimeter. Same thing happens with "neutral" side.
The isolation works. Any single one connection from either side of the isolated output will give you 0V to multimeter.
If you have two identical multimeters, and connect one from "phase" to ground and other from "neutral" to ground, you would get reading of 115V on both of them. The sum of those is that 230V. In this case your measurement circuit would consist of loop consisting of follwoign parts: floating 230V power source - multimeter 1 - ground - multimeter 2 - other end od 230V power source
If your multimeters are not ideantical, then the voltages you get on them can be different, but the sum of measured voltages would be always 230V AC within your measurement accuracy.
