Circutor MPC-20 - Page 28

--- MPC 20 & 50 TESTER - M-981136 (vers. BD) --- Page
28
DERIVATION OF THE FORMULA FOR STEP AND CONTACT VOLTAGE
The following equations are derived from the graph:
V Vp Ve ß Ve ß1
222
=+× +×( sen ) ( cos )
V
Vp Ve ß Ve ß2
222
=−× +×( sen ) ( cos )
Developing the equations:
V
Vp Vp Ve ß Ve ß Ve ß12
22 2222
=+×× +× +×sen sen cos
V
Vp Vp Ve ß Ve ß Ve ß22
22 2222
=− ×× +× +×sen sen cos
If the two equations are added, we have to:
V
V VpVe ß ß VpVe1222 22
22 222 2 22
+= + + = +(sen cos )
Solving Vp: Vp =
() ( )
()
VV
Ve
12
2
22
2
+
−
V1 = read voltage on injecting current at 0º
V2 = read voltage on injecting current at 180º
Ve = read voltage without injecting current