Posted ByLeon on January 16, 2002 at 01:18:54:
In Reply to: Re: Remote power on/off posted byKen Talley on January 15, 2002 at 11:37:56:
CAT5 should work OK. But do put a big E cap (1000 uf, 50V) near the power terminal to the PLC that is far away from the battery (is master or slave near the battery?). This provide a buffer to prevent a voltage drop when a load is turned ON by the slave. If the load current is very high you may need a bigger cap.
: I am going to use a master slave configuration and thought that it would be a good idea to power down both when not in use, maybe not, I don't know.
: The two PLC's are going connected using the RS 485. Do you think I would have a lot of problem using one of the pairs of a shielded CAT 5 cable for the RS 485 and another to pass power from the slave to the master. Of course the only power required for the Master would be for internal calculations and to input and display. All of the output is handled by the slave.
: If this scenario would work then in all reality I could use a third pair to control a relay from the Masters enclosure to power up both the slave and the master, couldn't I?
: Once again.
: Thank You for your time,
: Ken