PLC5 and Powerflex 700 wit RIO communications

I have a PLC5/40E PLC. It has a RIO network already connected to it. I want to add a Powerflex 700 with a 20-comm-r communications card to this network.
There are 13 existing nodes on this RIO network.

I want to send and receive the logic/status and speed reference/feedback signals.

Will ½ size give me the above or do I need to do extra messaging?
Is the reference/feedback 16 or 32 bit on the pf700 drives? If they are 32 bit, whats the best way of handling it in the PLC5.

I want to control the pump speed based on pressure. I was thinking of setting up a PID controller in the PLC5 to handle this. There are already 12 pid block setup in the PLC. They are using the PD structure.
Whats the difference between the PD and PID structure or does it matter which one select.

Do I need to do anything special in the PLC5 that I would not have come across in the new controllers or wouldn’t be aware of having only used the newer controllers.

I wont get much time to set this up offline either. I will have to do it in about a 3 or 4 hour window so I need to be very comfortable with the offline solution I come with when I go to implement it.

I have used controllogix and compaclogix PLC’s before but my knowledge on PLC5 is limited. I have used devicenet, ethernet, profibus and modbus comms before, but not RIO.



Any advice on how to implement the above on a PLC5 platform would be appreciated.

You'd have to check the user manual for the drive to determine what the feedback/reference size is for that particular drive. the 700S models use 32 bit, but the 700VC drives are 16 (or selectable between 16 and 32 bit, I forget). If the drive requires 32 bit reference/feedback, you will need to write code to convert the 32 bit numbers into 16 bit to use in the PLC5.

The 1/2 rack configuration will give you reference, feedback, logic status and logic command control through discrete I/O. If you want to use Data-links to pass information (torque limit, accel/decel rates, motor torque, motor current, etc) to and from the drive, I think you will need to set up block transfers.

Thanks for your reply,
The drive I am using is a 20BC037A0AYNANC0 which is a PowerFlex 700 drive. I believe the speed reference and feedback is 16 bit.
The speed reference units are 0.1 HZ. 0-500 = 0-50Hz.
I am controlling the drive speed from the output of a pid loop. To achieve this , I was thinking of setting the PID loop parameters,
Output Limit High%:500
Output Limit Low%:300
This would clamp the drive speed between 30 and 50 Hz.
The PID.OUT would only be used as the speed reference when the drive is in auto. If the drive is not in auto, I will move 300 (30Hz) into the speed reference.

The process variable for the PID loop will be a 4-20mA analog input which represents 0-10 bar pressure. The setpoint will be around 6 bar. I am using a spare channel on an existing analog input card (a 1771-IFE/C card). There is a BTW instruction setup to N15:144, length 39 and a BTR instruction setup to N15:122, length 22. I am using analog input N15:140.
The card is setup a single ended. What is the best configuration (scaling and any other necessary settings) for this channel to set it up to feed into the PID block.
Would I set my Eng min to 0.
Would I set my Eng max to 500.
Would I set my input Range min to 0.
Would I set my input Range max to 4096.
409.6 = 1 bar. To enter a setpoint, multiply the desired bar value (0-10)by 409.6. Hardcode clamps on the setpoint from 1-10 bar also.
Can anybody give me some direction on what I am proposing to do. I am not very comfortable using the analog input and pid instruction in the PLC5 yet.

Hello,

Can anyone give me some advice on the scaling with a 1771-IFE/C card. I am looking at other channels on the card that I was going to copy but dont understand how they are being scaled.

The other channels that I am looking at have 4-20mA inputs, representing 0-10 bar pressure.
The scaling max and min for the channels are 0 and 4096.
There is no further scaling (like a cpt or mul or div)done to the raw value on the input channel.
There are HH,H,L,LL status bits based on the value on he input channel.
LL is LES than 1000 (1 bar i assume) HH is GRT than 7000 (7 bar I assume) etc.
I am not sure how this apparent scaling is being achieved with 0 and 4096 as the min and max values.

I have seen this in the manual (Appendix A of 1771-IFE series C UM)and am not clear what it means,
engineering units sent to the processor +-9999 base10 with selectable scaling.

Is it saying that the processor automatically sees an analog input as 0 to9999 / -9999 to 9999 or that it is possible to setup these ranges.

hi , i ma TOO

i have problem , i cannot strat hrad wire of PF700. i using a 20BD011A0AYNANB0

gouch said:

Hello,

Can anyone give me some advice on the scaling with a 1771-IFE/C card. I am looking at other channels on the card that I was going to copy but dont understand how they are being scaled.

The other channels that I am looking at have 4-20mA inputs, representing 0-10 bar pressure.
The scaling max and min for the channels are 0 and 4096.
There is no further scaling (like a cpt or mul or div)done to the raw value on the input channel.
There are HH,H,L,LL status bits based on the value on he input channel.
LL is LES than 1000 (1 bar i assume) HH is GRT than 7000 (7 bar I assume) etc.
I am not sure how this apparent scaling is being achieved with 0 and 4096 as the min and max values.

I have seen this in the manual (Appendix A of 1771-IFE series C UM)and am not clear what it means,
engineering units sent to the processor +-9999 base10 with selectable scaling.

Is it saying that the processor automatically sees an analog input as 0 to9999 / -9999 to 9999 or that it is possible to setup these ranges.

Click to expand...

The Raw Min=0-Raw Max=4095 scaling is the default for a 12 bit 1771-IFE/C PLC5 Analog Input module since it represents the accepted resolution of a 0-20mA signal variation. Old school...Haven't seen one of these in years...
If 4-20mA represents the value of the input for 0-10 bar pressure variation I would scale the respective point of the module as Raw Min=0-Raw Max=10 for a coarse definition or 0-100, 0-1000, 0-9999 if more acuracy is needed.
+/- 9999 is the permitted Min/Max Raw since, again, this is only a 12 bit "memory sliced" device.

Thanks for the reply. I was hoping to get the install completed before xmas but it didnt work out. I will be getting the drive up on the rio comms and wiring in the pressure transmitter after xmas. I will now get a chance to do some work one weekend and finish the project on the following weekend. If I run into issues, at least I will have the week to sort them out.

I will let you know how I get on.