flopro

Make sure S:2/15 is not set in the Channel 1 status file. If it is then only one communication request is serviced per scan. You can also "sprinkle" SVC instructions in the ladder logic to force the SLC to do some unscheduled communication request servicing on either comm channel. Usually you want to control these SVC instructions with an XIC S:2/5 (incoming command request pending) or S:2/7 (outgoing command request pending). After doing this to a SLC 553 with 3 PV600's, RSView32 and RSSql the Ethernet network became so "snappy" that the customer's operations personnel thought the control system had been replaced. It had been sluggish for 3 years and PV's had hold times on the buttons and interscan delays extended unnecessarily. I observed through RSLinx driver stats >80 packets/sec. servicing RSView32 and RSSql OPC topics. Remember, there are 3 PV600's also on this network performing discrete batching operations for three production areas besides RSView32 and RSSql. In PLC5 platforms you don't have the SVC instruction but you can adjust the S:71 time-slice in ms to let the PLC processor have that much more time to perform housekeeping routines between scans; communication requests being one of them. Just be aware that this additional time is added to the overall scan time.

http://www.pwmcontrols.com/

Yes, it can be this easy and you'll be a-frigging-mazed! If I recall correctly, S:2/15 will impact the system dynamically and immediately by toggling it while online with RSLogix500 using the status file GUI. Remember to consider the other part of this 1-2-punch; the SVC instruction(s)...

Make sure S:2/15 is not set in the Channel 1 status file. If it is then only one communication request is serviced per scan. You can also "sprinkle" SVC instructions in the ladder logic to force the SLC to do some unscheduled communication request servicing on either comm channel. Usually you want to control these SVC instructions with an XIC S:2/5 (incoming command request pending) or S:2/7 (outgoing command request pending). After doing this to a SLC 553 with 3 PV600's, RSView32 and RSSql the Ethernet network became so "snappy" that the customer's operations personnel thought the control system had been replaced. It had been sluggish for 3 years and PV's had hold times on the buttons and interscan delays extended unnecessarily. I observed through RSLinx driver stats >80 packets/sec. servicing RSView32 and RSSql OPC topics. Remember, there are 3 PV600's also on this network performing discrete batching operations for three production areas besides RSView32 and RSSql. In PLC5 platforms you don't have the SVC instruction but you can adjust the S:71 time-slice in ms to let the PLC processor have that much more time to perform housekeeping routines between scans; communication requests being one of them. Just be aware that this additional time is added to the overall scan time.

Go to Channel Configuration>Channel 0 Pull down Driver menu and select Modbus RTU Slave Then assign the Modbus Data File Numbers for your 4 Modbus data types See attached help file page for details Modbus_RTU_Slave_configuration_.pdf

First and foremost-as painful as reality may be-you have to honestly determine if you have the mind/common sense when it comes to "logical thinking and "switchology"." Some of my technicians want to be set up with all the programming applications on their desktop/laptop PC. Usually I give them a reality check by asking them what makes them think they can write ladder codes for the equivalent of a pushbutton, relay, timer and lamp if they can't wire the hardware on the bench? No amount of formal education or training can teach common sense-methods, practices, procedures-maybe. But you either have it or you don't. Remember in coding, "Whoever does the most with the least is the best." I'm not a pessimist-just a realist.

Depending on which Micro Motion Flow Transmitter you are talkiing to, you may have the ability to reorder/swap the float bytes from the transmitter side. Also, some Modbus Polling Masters/OPC Servers have a float byte swapping feature. I always have to fiddle around with byte swapping settings on Micro Motions but we only talk to MVD core processors and sometimes 9739's.