I've been using AD PLCs on the majority of our machines for a few years now. So far, I've sampled the entire line except the DL305 series. Since the DL06 is relatively new, I've probably only used a dozen or so. Of those, I've had one D0-06DD2 that failed. Here's what I wrote at the AD forum:
- "I did have an output fail on one DL06 shortly after we shipped to the customer. It would not reliably close with a 0.2 second pulse. This PLC has become my 'shop' PLC.
It has one other weird characteristic. If I disconnect an HMI connected to port 1 at 9600 baud (the only speed for port 1) to connect my laptop, that port suddenly switches to 300 baud. I know because if I auto-detect, it connects at 300 baud. If I power cycle the PLC, it goes back to 9600. It does the same thing when I reconnect the HMI (and of course, the HMI can no longer communicate)"
I'm not positive whether the output itself was defective, or if it was damaged from the field device. In this case, that output was driving an AD brand card relay module, which has diodes built-in for spike supression. To be safe, I had the customer replace the PLC
AND the relay module. When I got the PLC back, I tested the output on a new relay, and the output still failed to operate properly.
I actually wish the output had failed 'out of the box', rather than waiting until the machine had shipped to Missouri...
IMO, poor Arik is simply having a string of bad luck. Unfortunately, since Arik is a new AD user, this makes AD look really bad...
beerchug
-Eric