PA 300 extension cord question.

Hi- I have a PA300 that I have been using for welding shed 40 pipe. The machine has been great so far. I especially like the portability of the machine. I really like the fact that I can have the machine close by as I move throughout the building by adding 8/3 extension cord to the 208V power supply. Can anyone tell me what the length limit is on 8/3 extension cord? Can I damage the welder by using too much extension cord? Would I be better off splitting the distance with lead? On the job I am currently on, I have to run about 250 feet from the power panel to the work on the roof. I would like to avoid bringing in a gas drive if possible. Please advise. Thank you.

With only 208, you better step up to 6 gauge as it is. There's plenty of charts that will give you the length and amp carrying capability. Just google it. Here's an example:http://www.stayonline.com/reference-...-ampacity.aspx
If you can, since you have 208, I'd assume three phase is available? I'd run it on that first if you are gong to use an extension. Yes, you can damage the welder on too little voltage if the voltage drop is below 208V. That's the lower threshold of operating the unit. When your operating on 208, you have the potential of pulling over the 60 amps its rated for...well over.