You are all missing my point!
I was mistaken about the current rating, which was from my memory, but it is still very differerent from the data sheet
The photo shows the markings on one of the relays. It is a Nais DS2Y-S-DC5V. It clearly shows 0.3A at 125VAC or 110VDC, or 1A at 30VDC.
Now if you look at the datasheet, the maximum switching current is 2A and the max carrying current is 3A. Even taking into account the switching power, of 60W or 62.5VA making the 30VDC off the case marking, this should still be 2A, or about 0.5A at the higher voltages. Also the datasheet states twice the max switching voltage to that shown on the case marking.
It's as though it's a compleley different relay.
So why would the manufacturer mark the case with one rating, and state a very different rating on the datasheet?