Operating instructions

Multiplexer

11.1.1 Take notice

If you work with the L1 Bus parallel to a PG, you must know that the PLC sets behind a

received L1-protokoll the receive-bit. You must query this bit to recognise that something is

in the receiver. Then you must clean the receiver. But comes a PG-protocol straight behind

the L1-protokoll, the PLC resets the receive-bit (the PLC says that something comes into the

PLC, but it wasn’t a L1-protokoll). To be sure that the program recognise that something is in

the receiver, you must scan the bit at difference places in the PLC-program. So you can be

sure that you doesn’t miss this bit. That problems can appear, if the PLC is slow or the

programs are very big.

If two operation panels are connected to the PG-MUX, both must be differently

parameterised, in case of that the operation panels haven’t the same FW´s and DB´s. If the

FW´s and DB´s are the same, the PLC can not distinguish from what OP the data was

transferred. That problem doesn’t appears when you use different FW´s and DB´s.

You should generally enter a `time-out` into your OP (if it is possible), because if a PG

transfers a large DB (for example), the OP must wait for the next conversation with the PLC.

If you increase the time-out, the OP waits for a longer time, can’t go into the ´time-out´. A

good time is 3-5 sec.

If the OP works with the PG-Protocol, it can may be that the OP addresses directly by

transferring data into a DB. Now if you make changes with the DB in your PG and transfer it

back into the PLC it can appears that the OP doesn’t recognise that there is a new DB into the

PLC and makes so transfers to the old DB (the old OB isn’t active in the system). To allocate

the PLC-memory, you must compress it (the PLC makes a new organisation of its system

organisation). The OP becomes a new chance to work correctly with the PLC.