Do you guys connect the secondary PSU on these PowerEdge servers that support and have dual PSU's installed?
I noticed the new PE 2950 I just ordered has dual but only one is currently powered.

Thanks.

In your case, the rack where your server is located doesn't have two separate circuits to gain much benefit from the dual PSU.

Talk to a sales person, they can initiate the NSR(Non Standard Requests) process, but they'll most likely need to move you to a private rack since running another circuit will have impact on the customers around your server's location.

I would have thought that even with a Y power cord you'd have the benefit of the power supply itself being redundant even if connected to the same circuit. (e.g. in the recent d5 power drop I know it was commented that a number of servers didn't come back up after power being restored due to power supply issues, so I would think that having both of a 2950's power supplies connected if a failure happened it would be sensed and the other would seamlessly take over with an alarm but the server running) I've had a few redundant power supply boxes, but never had a real-world failure, only a simulation, so maybe I'm being naive.

I think there concern is power usage per server on a phase.
Running two PSU's will require more power to be allocated per circuit.

The multi-phase option isn't there but yes, having that second PSU running with the Y-cord would be the bonus just in PSU redundancy. It is better than one.

One of the problems with the Y cord is the thickness. Since they're unable to handle as small of a radius as their thinner counterparts, they tend to stick out. The more cords that are sticking out, the more opportunities for it to become snagged on a person or another server while they're working in a cab.

We've historically had some issues with the Y cables, so we quit using them a while back, but there are quite a few racks where they were implemented.

Thats interesting.
Our 1950's use Y cables and are the same size past the Y to the NEMA 15p end as the two single power cables on all our other PE servers. All of our other servers are split so each PSU can be on one of the two phases we have.
In thickness, the standard issued Dell server power cables are much larger and longer than a standard desktop power cable.
TP must be using smaller power cables (in size but not AWG) and if that is the case, then I can understand the reasoning.

As far as I know TB use smaller cables.