The ebay 5 V relay boards...are they safe to switch a load of about 1500 Watts?!?they are rated at 250VAC at 10 Amps?By my understanding,if i connect a socket plug to a relay and the relay to the 1500W load,there will be a constant flow of 240 V and 6-7 Amps inside that small relay..are they safe to use in this conditions? at about 1500 Watts?
The load is heater that will start sometime in the morning and remain on untill late at night,so I assume the relay will be under a lot of stress(constant 240V@6-7 Amps for about 20 hours/day)..is it safe to proceed with something like this?!
Is a question more about safety and reliability..will it work or will it melt in a few days!? 
I find these are often rated say around 250v &10A according to the manufacturers.
Having said that these ratings can often look exaggerated on cheaper Chinese gear. Whats important here is that the terminal blocks, the actual relay unit and the PCB trace between them can handle the load. Oven on these sorts of boards you see the trace has been bulked out with more solder.
I don't think 10a @ 250v is that unbelievable on these sorts of boards but the temperature is always a good indicator of how its actually performing under load.
krishpants:
I find these are often rated say around 250v &10A according to the manufacturers.Having said that these ratings can often look exaggerated on cheaper Chinese gear. Whats important here is that the terminal blocks, the actual relay unit and the PCB trace between them can handle the load. Oven on these sorts of boards you see the trace has been bulked out with more solder.
I don't think 10a @ 250v is that unbelievable on these sorts of boards but the temperature is always a good indicator of how its actually performing under load.
I have the same fear..i think the terminals will melt or the tracers of copper on the PCB will get very hot or even worst,leading to a possible short circuit.
are these 12 V relays more reliable?!they still look flimsy and not up to the task for me