Womack Data Sheet 80: JIC Standard Symbols for Electrical Ladder Diagrams
These graphic symbols are the ones used most often on ladder diagrams for fluid power electrical control circuits. They are standard JIC (Joint Industrial Council) symbols as approved and adopted by the NMTBA (National Machine Tool Builders Association). They have been extracted from the Appendix of the NMTBA Specification EGPl-1967. Remember that JIC Standards are advisory only. Their use in industry or trade is entirely voluntary.
DEVICE DESIGNATIONS
These abbreviations are intended for use on diagrams in connection with the corresponding symbol from the charts above to amplify the information on the function of a device. Suitable prefix numbers (1, 2, 3, 4, etc.) may be added to distinguish between several similar devices. Suffix letters (A, B, C, D, etc.) may be added to distinguish between several sets of contacts on the same device.
Examples: 1-CR-A, 1-CR-B, 3-CR-A, etc.
| AM – Ammeter | GRD – Ground | RH – Rheostat | ||
| CAP – Capacitor | HTR – Heating Element | RSS – Rotary Selector Switch | ||
| CB – Circuit Breaker | LS – Limit Switch | S – Switch | ||
| CI – Circuit Interrupter | LT – Pilot Light | SOC – Socket | ||
| CON – Contractor | M – Motor Starter | SOL – Solenoid | ||
| CR – Control Relay | MTR – Motor | SS – Selector Switch | ||
| CS – Cam Switch | PB – Pushbutton | T – Transformer | ||
| CTR – Counter | POT – Potentiometer | TAS – Temp. Actuated Switch | ||
| F – Forward | PRS – Proximity Switch | TB – Terminal Block | ||
| FB – Fuse Block | PS – Pressure Switch | T/C – Thermocouple | ||
| FLS – Flow Switch | R – Reverse | TGS – Toggle Switch | ||
| FS – Float Switch | REC – Rectifier | TR – Time Delay Relay | ||
| FTS – Foot Switch | RECEP – Receptacle | VM – Voltmeter | ||
| FU – Fuse | RES – Resistor | VS – Vacuum Switch |
© 1990 by Womack Machine Supply Co. This company assumes no liability for errors in data nor in safe and/or satisfactory operation of equipment designed from this information.