Help Needed For VSD on the following

I am an automation Student and I'm new to PLC programming with Allen Bradley Rs Logix 500.

I have to upgrade an actual automated cooling wine fermentation process by using new a new PLC, HMI and implement the use of Variable speed drive.
I have (2) x 3Φ centrifugal KSB water pumps of 3kW output power each

Actual PLC : SLC 500 (1747-L532)
Proposed PLC : MicroLogix 1500 (1764-28BXB)
Proposed VSD : (2) x Vacon 0100-3L-0008-5-Flow

I would like to know if i will use analog output modules for the VSD ( Will the VSD use them)?

How analogue outputs are programmed in Rs logix 500 ( The Instruction blocks to be used etc)

Anyone can give me a guideline, a tutorial that can help me, or a proposition on how i can use the VSD for the 2 pumps?

Thanks in advance

Joe Frey said:

I am an automation Student and I'm new to PLC programming with Allen Bradley Rs Logix 500.

I have to upgrade an actual automated cooling wine fermentation process by using new a new PLC, HMI and implement the use of Variable speed drive.
I have (2) x 3Φ centrifugal KSB water pumps of 3kW output power each

Actual PLC : SLC 500 (1747-L532)
Proposed PLC : MicroLogix 1500 (1764-28BXB)
Proposed VSD : (2) x Vacon 0100-3L-0008-5-Flow

I would like to know if i will use analog output modules for the VSD ( Will the VSD use them)?

How analogue outputs are programmed in Rs logix 500 ( The Instruction blocks to be used etc)

Anyone can give me a guideline, a tutorial that can help me, or a proposition on how i can use the VSD for the 2 pumps?

Thanks in advance

Click to expand...

yes, you will need an analog output card with 2 analog outputs from the PLC to run the VFD's Speed Reference input. Usually the VFD's speed reference input can be programmed to be 4-20 mA or 0-10 VDC. I use the SCP (scale with Parameters) function in RSLogix 500 to scale my analog values, or you can use a CPT function to scale the output to something common like a 0-100% output to a 0-4095 raw data.

TEX

Unless you are being specified to use a Micrologix 1500, I would not use one. The Micrologix 1100 and 1400 are actually newer model PLCs that are faster, have built-in Ethernet, online edits, and are actually cheaper.

You could use modbus rtu communication probably cheaper. This way you can monitor the drive and there is a sample program for this application.

Have A Good Day
Tom

sparkytex said:

I use the SCP (scale with Parameters) function in RSLogix 500 to scale my analog values

Click to expand...

Can you please give me an exemple on how i can enter the parameters in the SCP for the analogue output controlling the VSD?

Helliana said:

Unless you are being specified to use a Micrologix 1500, I would not use one. The Micrologix 1100 and 1400 are actually newer model PLCs that are faster, have built-in Ethernet, online edits, and are actually cheaper.

Click to expand...

Unfortunately the ML1400 is not convenient for my process as i will be using 6 ( without considering spare) I/O module from 7 available. Am compelled to use ML1500.

wolverine1981 said:

You could use modbus rtu communication probably cheaper. This way you can monitor the drive and there is a sample program for this application.

Have A Good Day
Tom

Click to expand...

Can you please post the sample

Hi Joe

You should really consider using modbus communication between your PLC and your drives, given your drives are able to do so.
It's a bit more tricky than using analogue outputs but once you get it running you're able to read all the information you want from the drives, and I suspect that some of the reason for using VFDs is to save energy. This way you will be able to show the customer that it actually is.
Another benefit is that you will be able to reduce the I/O count which might let you choose a ML1400 and make your life easier.

I have had projects with ML1400 and Vacon drives in the past, all on modbus. I don't work for that company any more so I can't supply any sample code, but if you have specific questions we can help you out.
Remember to post as much relevant information as you can.

If you do go for the ML1400/modbus connection, get one of these breakout cables for easy connection on the ML:

1763-NC01

I AssUMe that your input for the VSD is needing to be the temperature of the wine fermentation process. If the VSD Speed (or Frequency in HZ) is to be proportional to the temperature (as temperature rises, VSD speed increases), then if your Vacon drive has a built-in PID instruction (many do), then you only need to send the Vacon a scaled temperature as a 4-20 miliampere input to the Vacon control terminals for analog inputs.

If the Vacon does not have the PID function, then use the MicroLogix PID function block, with the CV Output going to a CPT or SCP instruction to scale the output to match your Vacon analog input.