B&B Electronics ADAM-6066 - Manual - Manual (Page 263)

253 Appendix C
C.2.3 Normal Mode and Common Mode
Have you ever tried to measure the voltage between a live circuit and a
concrete floor? How about the voltage between neutral and a concrete
floor? You will get nonsense values. ‘Hot’ and ‘Neutral’ are just rela-
tional signals: you will get 110VAC or 220VAC by measuring these sig-
nals. Normal mode and common mode just show you that the Frame
Ground is the most important reference signal for all the systems and
equipments.
Figure C.4: Normal and Common Mode.
• Ground-pin is longer than others, for first contact to power system and
noise bypass.
• Neutral-pin is broader than Live-pin, for reducing contact impedance.