Any Sparky's on here? Comp wiring ?

[Mancar1]

In a way this is Bump related as I will use the new compressor when working on the 68. I need to add a 220 plug for the Engersoll Rand, 80 gal, 2 stage, 5 running HP. Here is a pic of my shop panel. Should I put it in place of 2 of those 20 amp breakers, or add it. I have the empty slots. I run a table saw, Large drill press, 110 welder, ect. Only one thing at a time of course. No elec heat in shop, wood stove. My shop has a dual pole 50 amp feed from the main house box. So I have 50 amp at the shop. I am wondering if a dual pole 20 amp breaker would be good for the compressor, or if I should go with a 30 amp dual pole.
I am picking up the compressor today, maybe the directions will lay it out. Ya right
Any input welcome. Here R some pics of main panel and shop panel. Top 1 Main, 2nd 1 shop, last one main. Thanks, John

[Mancar1]

Never mind all. I figured it out. Feed to the sub panel is plenty, and I am just adding a 30 amp dual pole breaker to it for the new compressor. I know how, I just wanted to hear it from someone else. So I called my Sparky buddy and he told me I had it figured right. No way I will every use enough at once to trip the 50 amp feed Thanks anyway.

[fordman]

the size of the breaker is suppose to be determined by the size of the wire feeding the recepticle.

[Mancar1]

the size of the breaker is suppose to be determined by the size of the wire feeding the recepticle.

Thanks fordman, and you are right. A 30 amp dual pole calls for 10 gage. I'm using 10/3.