S7 contrib VS plc industry palette

Hi at all.
i've a problem with palette s7-contrib and plcindustry.
My hardware in made of a Siemens IPC 127E ad PLC S7-400 rack.
In my project i exchange data from/to PLC e IPC. Data are temperature value that i send to plc for threshold control.
At the same time, i want send a single bit to PLC, but with s7-contrib ad PLC s7-400 i can't do it, but witn S7-300 plc i can do it. Instead when i use the plcindustry palette, i can do it also in S7-400 PLC.
Another case is when i want use ah Softonic IBHnet S7 for comunication between IPC and S7. With PLCindustry tha comunication fall down very frequently, instead with s7-contrib i can comunicate usign IBHnet, but can't send a single bit.

Is there anyone that say me own experience?

Thanx at all.


Then dont use bits! use bytes or integers.

TBH, writing bit values direct to PLC is not optimal and is untraceable.

In my previous role, I favoured writing a positive INT value to a WD address and using ladder to SET or RESET the bit depending on the value written.

This has the advantage of meaning if the PLC memory is reset, then the WD address being zero has no affect on the BIT (fuzzy logic)

This has method has another side advantage of making bit BIT cross-referenceable (i.e. findable by maintenance staff - they wonder HOW/WHY a bit is magically turning off/on out of thin air. The cross-reference it and find it linked to a DATA area labelled up as "Node-RED control" - mystery solved)

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