I want to connect my ac unit 208v need 20a fuses, to my stove plug which have a 50a 250v type outlets.

I have this
http://images.marketworks.com/hi/58/57750/pas5864-bku-ea-2.jpg

And want to fit into this
http://applianceguru.com/dryers/dryer_outlet.jpg

First, I hope your a/c says 208/240 not just 208.
Second, that is a 30 amp dryer receptacle you are showing, not a 50 amp stove receptacle.
Third, the plug is a 20 amp, 125 volt plug. Its not going to physically fit either a dryer or a stove receptacle.
Finally, if you do rig up some kind of connection, you are going to have to reduce breakers to 20 amp.

First, I hope your a/c says 208/240 not just 208.
Second, that is a 30 amp dryer receptacle you are showing, not a 50 amp stove receptacle.
Third, the plug is a 20 amp, 125 volt plug. Its not going to physically fit either a dryer or a stove receptacle.
Finally, if you do rig up some kind of connection, you are going to have to reduce breakers to 20 amp.

Yes it is a 208/240
I just found the wrong picture but it is a 50amp no "L" on the White wire side
Plug is very much a 20a 250v plug. Because horizontal side is on the right if ground is towards the bottom.

Yes it is a 208/240
I just found the wrong picture but it is a 50amp no "L" on the White wire side
Plug is very much a 20a 250v plug. because horizontal side is on the right if ground is towards the bottom.

http://lh3.googleusercontent.com/3dtJ1CiDiJKQ-3t4RBf9tFBiwDbT2w8uQ5aCdSWJ4lo7x89TPm7KqXrRGyaEIfI tcl8Z2sec7tHJUy9bGMWroxxiN-N6qgakVydmikIq3WYi6j5znU6q1aY4n75KNwruwWtrfjiiBRox j_bU8bWbNlsdYugelShNKie66mM

http://ecx.images-amazon.com/images/I/41Uh3X5W3EL._SS400_.jpg

My apologies, you are correct, that is a 240V plug. Be absolutely certain that you reduce the breakers to match the wiring you use for the extension.