slc500 or compact logix

[terrypnz]

Hello
We are looking at upgrading some equipment. At present this equipment uses a AB PLC5 and panelview 1400.
We have been back to the manufacturer of the equipment and they are advising an upgrade kit to a AB SLC500 rack and 1250 Plus PV.
My questions are.
Is the SLC500 old technology and what is the expected life expectancy of this processor (parts and support)?
Would we better to upgrade to a compact logix platform?
Any advise greatly appreciated, Terry

 

[Psymon]

http://www.youtube.com/watch?v=mZxG-8tHmqM

Go with the ControlLogix, especially if you're upgrading from 1771.

 

[TConnolly]

Welcome to the forum.

A CompactLogix is significantly less money than a SLC500. AB is using a pricing scheme that is designed to steer customers away from the SLC platform and towards the ControlLogix and CompactLogix platforms yet still support customers who have to support existing SLC platforms.

Since the PLC/5 has a superior instruction set, depending on what you are doing, you may find that the SLC platform doesn't have what you need to begin with while the CompactLogix platform will.

The CompactLogix platform is superior to the SLC but you should evaluate a ControlLogix platform as well, it offers significant advantages over the CompactLogix.

 

[James Mcquade]

terrypnz,

the Slc500 while it is very old technology, it runs and is reliable.

they are scheduled to be in the silver series within the next 2-3 years, so i would go with the control logix.

we are beginning to transition to the control logix platform
using plc 5 and slc 500 racks as remote i/o

regards,
james

 

[Helliana]

I would also recommend sticking with the CompactLogix platform but it also depends on what the equipment does and the personnel you have supporting the machine. If the equipment is going to have several drives and different kinds of I/O, a compactlogix is going to make things significantly easier, quicker, and cheaper to implement. If there are very large amounts of I/O, you should be looking into a Controllogix platform. HOwever, if you have this much I/O, you should never have been looking at a slc500 anyway. If its a fairly simple system with mostly digital and some analog I/O, I'd strongly recommend a Micrologix1400.

The only reason I would recommend a SLC over the compactlogix is if your maintenance guys have no clue how to learn the newer Logix5000 platform and but can somehow support the Logix500 one and your management don't want to spend the money on Logix5000 software. If this is the case, i would recommend the SLC500 and start looking for more skilled maintenance guys ASAP, or find yourself a better place to work. One day you WILL have to bite the bullet and upgrade to a Logix5000 system. Its probably easier to do it now than later.

 

[ComfortCoveCottage]

Don't worry about the cost of the PLCs. The price is insignificant over the long run and I'm sure the process that it will be controlling is worth MAGNITUDES more in revenue than their cost.

What you should be focusing on is the maintenance of the code. Think about it... how long has your AB PLC5 been in use?

Most PLCs manufactured today are reliable so think about the next engineer who will be modifying your code or adding onto the system long after you are gone from this current role.

 

[dmroeder]

There are some good points there about the SLC platform. Your maintenance department will be more familiar with SLC. RSLogix 500 is more like RSLogix 5 than it is to RSLoggix 5000. However, the Logix hardware will certainly be around longer. Consider the amount of time that you have gotten out of your PLC5, you should get similar out of CompactLogix or ControlLogix.

SLC platform should be around for many more year, but they have been pricing CompactLogix such that it makes more sense to buy it over SLC hardware.

I'm thinking that if the OEM is suggesting using a SLC, then there is no reason that you shouldn't be able to use a CompactLogix (vs a ControlLogix). I.E. ControlLogix is almost certainly overkill.

 

[RonJohn]

While I agree with the others above me, let me add another thought. If the PLC 5 used Remote I/O or DH+ communications, you will need to plan for an alternative to blue hose with the CompactLogix. There are work arounds if you need to stay put, like a 1756 E-net to DH/RIO bridge, but it would be more expensive.

Even though the SLC format would be an easier conversion, I would still lean towards Logix platform products for the long run.

Best regards,