relaysolid-state-relay
I want to know what are the different values written on the relay
I understand:
But then what are the remaining values?
NC vs NO is is usually a different current at the same voltage (if the ratings are, in fact different).
More likely the differences you cite would refer to compliance with different safety agencies.
For example, this one:
Should not be used at more than 125VAC if you need compliance with Canadian and US safety requirements-- the cURus component registration. The other rating refers to other safety agencies.
I think their concern is that with the inductive load, when you open the relay it will force some current across the open contacts and spark, damaging the contacts. A TVS diode should protect you, and you'd need to choose values above the mains voltage (peak voltage, not rms). In this case you'd want >170V. This wouldn't protect it 100%. I think you'd still have some current forced across the gap a tiny fraction of a second after opening it (before the voltage across the relay surpasses 170). So I can't say how much above 3A you'd be gaining.
The other option would be a bigger relay of course.
Best Answer
There are Agency Approval Symbols on the left and right side, above the values.
These symbols represent the approvals for those standards.
Some countries like US, Canada use Mains electricity around 110 volts. The "C" and the "US" markings (on the right) signify that the component is UL recognized in both Canada and the United States.
Thus, values below that symbol are the values for the US and Canada market/use.
The values on the right side are for use in countries that use Mains around 220 volts:
Different Agency Aproval Symbols can be found here: http://www.jameco.com/Jameco/marketing/agency-symbols.html