Most common receptacle - domestic
5-15 General purpose (mostly duplex; one over the other)
1-15 Obsolete but common on old properties
5-20 Mainly dedicated equipment (mostly single; furnace, pump etc)
6-20 Workshop; air conditioners *
10-30 Dryer (old)
10-50 Stove (old)
14-30 Dryer (new)
14-50 Stove (new)
rare are 6-30 and 6-50 for welding machines
Most common plug – domestic
1-15 Most equipment is class2 (including metal jacketed toasters!)
5-15 Class 1
6-15 240V stuff *
then as above
Note that the connectors for 30A and above are about 1.5 times the size of those 20A and below so what appear to be similar geometries are not. Most installations have the ground pin at the bottom – a source of passionate debate on the other forum.
Bjarney et al.
may be able to enlighten you on the industrial side.
* I'm using a personal based example and normally these would be only slightly more common than the welders
[This message has been edited by Hutch (edited 01-03-2004).]