Difference between A/B Devicenet 24VDC Power Supply and Regular Power Supply

Is there anything really special about Allen-Bradley's 24VDC Power Supplies for Devicenet?

I say NO. Unless you consider the cost

The first thing is that they do meet the specifications for rise time, voltage stability, short circuit protection, etc. that the ODVA recommends for DeviceNet network power supplies.

The second thing is that they've been run through the ODVA tests for power supplies, to prove that they actually do the things the specifications say they do.

DeviceNet doesn't require anything *special* for the power supplies, like ASi does. But it recommends certain performance characteristics, and buying a power supply that's been tested and conformance-marked is an easy way to be sure it's going to work in that application.

Shop around - DeviceNet is not exclusively AB territory, you can get DeviceNet "certified" power supplies from many places.

I don't think A-B still sells the enormous 1787-DNPS, which was oversized just to get a specific ODVA specification. You'll be looking at the 1606-XL series, which are from the same German OEM that Sola used before they went to a Chinese vendor.

Only the 1606-XLDNET4 and -XLDNET8 were run through the ODVA process because they fit the maximum size for Class 2 and Class 1 on-machine wiring. In my experience the other members of the 1606-XL family have the same performance but lack an ODVA test suite and checkmark.

I use mostly Phoenix Contact QUINT series power supplies, with A-B 1606 as our alternate spec. I won't use IDEC power supplies no matter how good their pricing is. Your mileage may vary.

Cost

AB is different from regular one is high cost and standard material used. And more important Voltage stability.

For Devicenet, make sure what ever supply you buy, meets the specs. I have been down that road of getting stuck with using a substandard power supply, then later having problems (with rise time IIRC) as nodes were added.