| ??? 10/08/06 10:41 Read: times |
#126007 - Excessive use of COM? Responding to: ???'s previous message |
We have the net COM on the transzorbs on the input side as well as on the cpu side of the optos. If this is one and the same, then why use optocouplers? On the PLCs i've looked at, the leds are on the cpu side of the optos - at leadt you know if the led is on, then the cpu is seeing on also. This may help diagnosis by ensuring the led only is on when the input is on and not a low voltage that is not enough to fire the opto. |
| Topic | Author | Date |
| LED Resistor Drive Circuit | 01/01/70 00:00 | |
| A is good, C is bad, B is a huge maybe | 01/01/70 00:00 | |
| LED with integral resistor | 01/01/70 00:00 | |
| Resistor Network? | 01/01/70 00:00 | |
| LED circuit | 01/01/70 00:00 | |
| Bruces Design Example | 01/01/70 00:00 | |
| Excessive use of COM? | 01/01/70 00:00 | |
Thats it | 01/01/70 00:00 | |
| the resistors are current limiters | 01/01/70 00:00 |