what A-B PLC should I migrate to?

[Skidood]

Hi Group
Hope everyone is ...not too shabby.
I developed a program using RSLogix 500 for use on a MicroLogix 1400.
I need to update to a newer platform using essentially the same program (with whatever mods might be needed to suit the new PLC). (Hoping to keep the mod work to a minimum)
Looking for recommendations as to which PLC.

PLC requirements:

12 relay outputs
4 DC inputs
4 RTD analog inputs
1 4-20 mA analog input
1 port for HMI, 1 port for RS-232 serial ASCII interface to a printer

The program has (along with the basics) the following instructions in it which are a must but may not be usable on some lower end PLCs:

AWT (ASCII Write) for sending data to the printer
ACN (ASCII Concatenate) so i can assemble an ASCII string before sending to the printer
SCP (Scale With Parameters) for the analog inputs

I have RSLogix 500 and RSLogix 5000
The PLC and any added modules need to be as small as humanly possible. Esp. the length of the overall assembly) This is also extremely important.
I am using an Automation Direct HMI which I plan to keep using.

Any suggestions would be very much appreciated. Thanks in advance!

 

[Engineerj22]

If AB.

compactlogix rack.

1769-L16ER-BB1B for the processor
1769-OW16 for the relay outputs
1769-IQ16 for the DC inputs (assuming 24VDC in)
1769-IF4 for the analog IN
1769-IR6 for the RTDs
1769-ASCII for the printer.

What comms does the HMI use?

How much room do you have?

 

[geniusintraining]

I have RSLogix 500 and RSLogix 5000

1769-L16ER-BB1B for the processor

The L16ERwould be a good fit but you may also want to look at updating your software to Studio as I dont think 5000 will support it

You may also want to look at a 1769-L24er or 27 if you can find them

 

[Engineerj22]

The L16ERwould be a good fit but you may also want to look at updating your software to Studio as I dont think 5000 will support it

You may also want to look at a 1769-L24er or 27 if you can find them

L16ER does version 20.

I just made a list with the cheapest (haha rockwell) parts.

L24 or 27 would be better though

 

[geniusintraining]

Looking here https://compatibility.rockwellautom...518,51519,51511,51512,51513,51535,51527,51528

They show the first version being Studio V21.... but they also show V32 is not compatible, I still use V24 on them

 

[Engineerj22]

@geniusintraining

What rockwell's website says and what actually can be done are, as usual, 2 different things.

edit, noticed I used the L18ER in the rslogix pic

 

[Engineerj22]

LOL

Found V33 firmware for L16.

 

[Skidood]

If AB.

compactlogix rack.

1769-L16ER-BB1B for the processor
1769-OW16 for the relay outputs
1769-IQ16 for the DC inputs (assuming 24VDC in)
1769-IF4 for the analog IN
1769-IR6 for the RTDs
1769-ASCII for the printer.

What comms does the HMI use?

How much room do you have?

Thank you. The HMI to PLC comms is currently with serial. Although the HMI also has ethernet. Size-wise, what you recommended would probably take up a wee bit more space than what I'm currently using with the 1400 plus 2 input modules. I really really don't want to go much longer than this (rack length) but probably don't have a choice.

If going over to the CompactLogix platform, i guess I will have to acquaint myself with the differences in how the MicroLogix and Compactlogix PLCs scan and execute. My limited understanding is that one is synchronous, the other asynchronous....or some thing like that. Will have to read up on that.

 

[drbitboy]

... My limited understanding is that one is synchronous, the other asynchronous....or some thing like that. Will have to read up on that.

An input map is one way to eliminate possible issues there cf. here.

 

[Engineerj22]

Get a network switch, AD HMIs work well with AB PLCs over ethernet. I don't know about the asynchronous and synchronous of the PLCS. I know you can have the compact have continous and periodic tasks.

 

[PLCMentor]

Any of the logix processors update asynchronously. They can update in the middle of your routine. The older processors, such as the 1400, update inputs before the program scan and outputs after the program scan. One way around this is to copy inputs to tags at the beginning of a routine and outputs at the end. I have never really found it to be a problem. If you are going through the trouble to upgrade then go to a newer processor that supports the latest firmware. No reason for you to upgrade from vintage to old.

 

[Ken Roach]

The fact is that the "Shoebox" form factor is very successful and compact, and a migration to a more-granular or chassis style is probably going to be less compact.

Some folks recommended the smallest CompactLogix (the 1769-L16/18/19). Despite their membership in the Bulletin 1769 family, those controllers use the 1734 POINT I/O platform, not the 1769 Compact I/O platform. POINT is great for granularity, but the module count goes up fast when you need 16 relays and have to add them 2 or 4 points at a time.

If the relay outputs can be served by DC solid state output points instead, then the 1769-L1x CompactLogix might work better. The small number of RTD, analog, and ASCII features line up nicely with POINT I/O.

The most appropriate controller for this application might not be a CompactLogix, but rather a Micro 850 or Micro 870.

I strongly prefer Studio 5000 to CCW, but for an OEM application the hardwire might dictate the selection.

The 2080-LC50-48QWB model of the Micro 850 has 28 DC discrete inputs and 20 relay outputs, and both a serial comms port (for DF1, Modbus, or ASCII) and an Ethernet port.

It has room for up to 5 "plug in" modules:

2080-RTD2 (2-channel RTD)
2080-RTD2 (2-channel RTD)
2080-IF2 (12-bit analog input)
2080-SERISOL (serial port for ASCII, if you don't want to use the integrated one)
2080-MEMBAK-RTC (Real Time Clock, EEPROM or Data Log storage, if necessary)

 

[Engineerj22]

DOH! I forgot the smaller ones used point IO! I'm used to the bigger and older L30s!

 

[PLCMentor]

Yeah I'm not really a fan of the point I/O either. I'm not sure how much room you save with a slot type of card architecture as most people I know take those to interposing terminals. I've had a lot of success with the older compacts and the new Compacts that expect point I/O, networking to Flex I/O instead. I recently had a situation where I had to use the point I/O due to space constrictions on a system upgrade, but most times the flex has worked out great.


I have not seen anything good concerning the Micro 8xx stuff. Seems like it's a nightmare put into practice. Until I hear somebody that likes it, I'll stay away from that line. Also the problem with OEMs standardizing on something like that is the limited number of end clients that will accept it. Many users have their own specifications and if you standardize on something that nobody will accept then you end up redesigning every job.

 

[AustralIan]

I know you said AB, but if you can stretch it to 'Rockwell', the ASEM LBM40 is a Rockwell PLC that runs codesys.
Just need your choice of remote IO for it.