Im a 2nd year apprentice electrician and work in the oil field out of midland TX. Lately ive installed some relays which I believe to be single pole single throw. They are being used for murphy switches to monitor high pressure on the head of a oil well. Without the relay the switch will feed back to midget fuses and blow one or more of them, after being tested. They are installed and working, however some of the symbols and meanings I do not know nor understand the function fully. Can anyone with this knowledge help me understand the symbols and function and proper ways to wire them. Any info you can supply would be helpful and appreciated.

 

http://forum.allaboutcircuits.com/showthread.php?t=69884

 

Show some of the symbols or a part of the circuit.
There is also a different symbols used if this is European based equipment.
http://static.schneider-electric.us/docs/Machine Control/0140CT9201.pdf
Max.