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Testing Switch Shuntings, Advanced

The following is advanced information regarding switch identification by the internal shunting.
For further confusion in determining a replacement switch, some port markings are out of numerical order. This is not a problem if you replace the switch with another that has the same "out of order" numbering, but sometimes the same switch is available with a different casing. In which case, finding a replacement will require converting the actual numbered positions to the physical positions. The following describes one way to do this.
Look at the top surface of the switch were the number markings are written. Counterclockwise, the numbers should be in order 1-2-3-L. If they are not in order, consider L an anchor point. Counterclockwise from the L should be 1. Make a note that whatever number is here should be 1. Counterclockwise again should be 2; make a note that whatever number is here should be 2, counterclockwise again should be 3; make a note that whatever number is here should be 3. For example the following switch has port markings that are out of order. 3-1-2-L
Pos1Pos2Pos3Pos4
0L+1L+2+3L+3

So, if 3 should be 1, 1 should be 2, and 2 should be 3, the new chart looks like this...
Pos1Pos2Pos3Pos4
0L+2L+3+1L+1

Please note that the one manufacturer makes both of the switches above - Well-Tec. Another manufacturer makes a very similar switch but uses 2 as the anchor (That's where the black usually ends up)...
Pos1Pos2Pos3Pos4
0L+21+2+32+3

The switch noted above with the numbers out of order, is the Well Tec 108 and we have not seen another like it. It is a handy identification tip. These switches are currently being made. At first we thought it was some sort of production mistake, but if you look at the internal shunting the numbers have been re-arranged to be logical when wiring it up. Perhaps it was a combination of logical wiring sequence and easy identification, the made Well Tec create the switch casing like this.