PLC5/60 DH+

[frank.raymond 0]

Hello again, I have a PLC5/60 with port 2A configured for DH+ and port 2B configured for RIO. I want to add a PC/KTX for an HMI/DH+. I believe I can parallel off the processor onto the existing port 2A (beginning of DH+ run) and move to the terminating resistor to the new node connector. I also have ports 1A & 1B. Can there be mutiple DH+ ports on a single processor? When I hear about the traffic/bandwidth on a given DH+ run it leads me to believe you can to help offset the traffic but on the other hand I don't know for sure. I was going to use port 2B (read the help section regarding using port 1A and it scare me away quickly). Assuming it is possible to use another port for multiple DH+ how do I determine the Global Status Flags file? Can I duplicate port 1A's file of 40? I will only have the PC/KTX on this bluehose. Thanks for any and all feedback

[ratcliffe_ic 2]

I use the following strategy on PLC5, using the ports in the following way: 1A - DH+ - inter-plc messaging network 1B - RIO - PLC I/O, RIO devices 2A - DH+ - network for computers (including engineering laptops) 2B - DH+ - comms with operator interfaces My global status file is set to 0 in all cases as I am not using this facility, if you require this you will need to allocate a spare file address. In your example I would set up 1B to dh+ for your HMI. Port 1A is configured for DH+ by default, the difference is you need to set dipswitches to change this nodes configuration which means pulling the processor out.

[Ken Moore 23]

Since the global status file is used most often to pass one word form plc to plc, and you are not connecting any plc's, I would not create a status file for the additional DH+ port. Just my 2 cents worth.

[frank.raymond 0]

What is the purpose of the global status file? I failed to mentioned DH+ is also connected to 6 SLC504's where bit data is shared. And speaking of sharing thanks for sharing ya'lls information (that Southern for you all)

[Ken Moore 23]

When using the global status file there is a memory register in each plc for every possible node (64), plus a "broadcast" register, each plc can be configured to use this or not. When each plc receives the token, it broadcast the contents of it's broadcast register. Each plc that is configured, then places the broadcast value in the corresponding node register. It's a fast simple method of transfering one word per plc, no MSG instructions are needed. In the PLC-5's the global status file is defined by the user, in the SLC's it's fixed as part of the status file. It should be the last TAB on the far right, labelled Global Data, if I remember correctly the registers are S:100-S:163. Take a look here: LINK1 LINK2 look at pages 10-4 and 10-5 in LINK2