John Thornton wrote: > Where should the 208v be? The mains are 244vac. > If you measure from the mains neutral (which is NOT the center point of the 3-phase system) to the generated leg, it should be about 208 Volts.
The three-phase system is an equilateral triangle, with each side 240 V. The neutral is the center of the bottom side, the 240 V mains are the left and right corner of the bottom. The generated line is the top of the triangle. So, if you cut it in half vertically, you have two 30/60/90 degree triangles, with the 90 degree angles against each other. The left and right sides of the big triangle are also 240 V. So, the hypotenuse of the 30/60/90 triangles are 240, the base is 120. sin (60) * 240 = 207.8 So, that's where the 208 comes from. If your mains are actually 244 V, then neutral to L3 would be 211.3 V. But, you really should not be measuring from the mains neutral, as that is not germane to the 3-phase system. Just measure from each line to another. You should get 240 on each one. I have not derived the math on this, but I am pretty sure that it is impossible to have 240 V from each line to another and have the phase angles wrong. So, if the voltages read balanced, the phase angles ALSO have to be correct. Jon ------------------------------------------------------------------------------ Live Security Virtual Conference Exclusive live event will cover all the ways today's security and threat landscape has changed and how IT managers can respond. Discussions will include endpoint security, mobile security and the latest in malware threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
