1734-IE4S safety analog input issue/ not reporting value

[joseph_e2]

I used it a couple of times, it filled the gap between a non-safe processor and the need for something more than the simplicity of a simple safety relay. Didn't know it was dis-continued, thanks for the update.

Have you used their 440C-CR30 safety controller? I tried them in an application that needed 3 hard wired safety relays and it was just barely able to handle the I/O count. Without being able to expand the safety I/O, it didn't seem cost effective at the time, but you did get some diagnostic info in Logix at least.

 

[jstolaruk]

Have you used their 440C-CR30 safety controller? I tried them in an application that needed 3 hard wired safety relays and it was just barely able to handle the I/O count. Without being able to expand the safety I/O, it didn't seem cost effective at the time, but you did get some diagnostic info in Logix at least.

I have, and like the SmartGuard, it also filled a one-time need. And you're right, the status and the diagnostics proofed helpful. With advent of the Guardlogix in the Compactlogix family, I haven't designed around it in quite some time.

 

[Steve1972uk]

Thanks guys,

Yea, I've double/triple checked the voltage output and the 24v is not present even tho the PWR light says it is. Comparing to the 'good' module next to it the 24v is present.

I've swapped the modules but I then simply get the MS or NS lights (can't remember which) flashing on both, I'm guessing each module is 'addressed' to that particular slot and can't be swapped without a program/configure change??

Managed to purchase another module and got a PLC programming guy coming in on Tuesday, hopefully he can sort it.

 

[Steve1972uk]

Hi guys, Just an update on this.

Unfortunately, the 'new' card was second hand and also had the same fault.
We swapped the faulty card with a working one next to it and transferred the fault to be sure that it is the card that has the problem and not a field wiring fault.

These cards are extremely difficult to get hold of, I've been quoted for a brand new one but with a lead time of March 2024!

Any ideas?
Could i replace the 1734-IE4S with a !734-IE4C?

 

[jstolaruk]

Yeah, all 1734 safety components have ridiculous deliveries. You could use a 1734-IE4C, it would violate/deviate from the risk assessment that was performed that generated the need for the safe version in the first place.

You would need a programmer to make some changes: remove and replace the IE4S with the IE4C in the I/O configuration, and if the IE4S signals are used in the safety task, the non-safe values would need to be accessible to the safety task via "Map Safety Tags" option.

Little bit of work involved but can be done if approved by those that are involved in the safety stuff.

 

[Steve1972uk]

Hi Jstolaruk,

Thanks for the reply.
Yea, not entirely sure the need for the safe version, maybe just 'over engineered'. But good to know that this is possible.
Just looking further into this, do you think the IE2C modules would be better as these supply the 24v i need for the 4-20mA current loop.

 

[jstolaruk]

Hi Jstolaruk,

Thanks for the reply.
Yea, not entirely sure the need for the safe version, maybe just 'over engineered'. But good to know that this is possible.
Just looking further into this, do you think the IE2C modules would be better as these supply the 24v i need for the 4-20mA current loop.

The electrical design would need to be reviewed.