AB 440-CR30 Safety Relay - Limitations?

[memphiskt007]

Hello,

Does anyone have any experience with Rockwell's Guardmaster 440-CR30 safety relays? As I understand it, you need to use Connected Components Workbench to program these devices. Everything I have read indicates you have 2 "Logic Levels" to program with. This seems like a fairly serious limitation. If you have experience with CCW, some design insight might be helpful here.

 

[Jeev]

I've used them in a fairly advanced application in the past. Programming wise they are not a problem, but once you require more I/O, I would highly recommend not connecting them together, and just going for an expandable system. I had a setup using 5 of the things connected together to cover the safety requirements of a single machine. It was difficult to understand the design and also difficult to troubleshoot. Basic/Standalone applications - Great. Advanced applications - Not great.



In regard to your logic limitation, I'm not sure what that's referring to. CCW is free to download, so grab a copy and set a project up to see if it will achieve what you want.

 

[brianschriver]

Hello,

Does anyone have any experience with Rockwell's Guardmaster 440C-CR30 safety relays? As I understand it, you need to use Connected Components Workbench to program these devices. Everything I have read indicates you have 2 "Logic Levels" to program with. This seems like a fairly serious limitation. If you have experience with CCW, some design insight might be helpful here.

CCW is free and easy to use (with the 440C-CR30) and is a good option. Another option, if you are connecting it to a Logix controller, is to use the Add-On Profile in Logix Designer / Studio 5000. It has all of the configuration and troubleshooting capabilities of the CCW implementation. Basically, Logix users do NOT need CCW for anything on the 440C-CR30.

Regarding the two levels of logic - you can "nest" the logic functions. In other words, if you are using a logic block to "AND" two inputs, this logic block can be an input to an "OR" block immediately underneath it. And this "OR" block could, in turn, be nested to another logic block immediately underneath it. And any of these blocks can then be passed to a logic block in the second logic level to the right. This really makes it much more flexible than two levels might seem. See attached screen capture for an example. (Note, this capability was added in FW release 9 several years ago.)

 

[dmargineau]

The only two logic levels is a severe limitation, however, the Logix Designer EIP AOP and Logix Designer programming interface (I believe for V30 and newer) makes Logix systems integration a breeze; there is no need for CCW; the 440C application is part of the Logix Designer project.

 

[Rson]

Haven't used them in years, but glad to see the logix 5000 integration.

For my money, it was always better to use something like a Jokab safety PLC that could be programmed and exapnded. Back when I was doing heavy safety-stystems, they were about the same price if I recall.