Solid State Relay - power spike?

I bought a Fotek SSR 40DA (40amp) and installed it in place of the power switch on a 120volt power bar.
I had my hakko soldering station (888d) close by so I plugged it into the power bar. The soldering station was left on -- then turning the SSR off/on (via arduino) 3 times every 5 seconds then blew the fuse on the soldering iron. I tried a light after and it worked fine.

I am a bit confused as to how this could happen? The soldering station is only a few months old. Of course the fuse is soldered in. I did use a current limiting resistor on the arduino output - 270 ohms i believe, which i found is not required.

I am afraid to plug in any electronic devices into this. Can anyone shed some light on this?

thanks.

My question is why turn it on and off 3 times every 5 seconds?

The soldering station probably has electronic circuitry that did not like the switching.

Weedpharma

Like I said, I was just testing. I didn't immediately notice that I killed the fuse. I guess lessoned learned is don't power cycle your soldering station with the power switch left on.