I have an Arduino. A suitable relay can be directly connected to an Arduino (with a flyback diode) if its coil is rated at 5 V and 40 mA maximum. However such relays have a limit on the voltages and current they can switch.
Can I exceed the contact rating of such relays if, for example, I was switching-on the relay for a short time of say 0.2 seconds and switching-off the relay for a relatively longer time (say 0.4 seconds)?
It seems that it could switch higher voltages than designed for, if the on-time is very short and there is a relatively long off-time after that quick pulse. This would of course give a cheap way (no relay driver circuit used) to control high voltage.
Is there any real danger of doing this?