Why Does NO Contact of Auxiliary Relay Show 230V AC With No Load but Bulb Won't Light?

in an electronics pcb we get 230v ac output which is supplied to common contact of a normally open contact of an auxiliary relay, which give 230v ac output when it energised. but at de-energised condition it shows 230v ac voltage (measured by a digital voltmeter) at its NO terminal though it unable to glow a 230v ac bulb. whereas at energised condition it shows 230v ac output too and bulb glows fully which is connected to relay output and a neutral point.

please help me to establish it's proper cause.

Hi Sovon,

Can't visualize clearly this case, however, for what I understand you are referring to the potential difference of this system, energized or not and why it is the same. So, the thing is that it has always a Potential Difference between the + or supply side and neural side or the device side to ground, connected or not.

Hope it helps.

God Bless.

Best,
Neil