Is there such a thing? I have been taught to take it out and slap it against the palm of my hand to hear if the contacts are loose, but sometimes they are positioned so that removing and re-installing can be a pain. Is there an easier way?
"If you've eliminated all other possibilities whatever remains must be the truth."
The problem is that line voltage will not be enough to open the contacts on a good potential relay. You would need to know that the drop out voltage of the relay in question is and you would need a step up xfmr to apply the drop out voltage.