I'm looking for a good way to audit the per-rack power utilization in an existing server room. Each rack is powered, for the most part, by a pair of single phase 30A/208v feeds. Is there something like a network-accessible clamp meter I could attach to the power cords that would let me record current draw over time? Would something like the TED 5000 work for this purpose? Actually replacing the PDUs (with, say, metered PDUs like the ones available from APC) isn't an option at this time; this is part of a planning effort for a new data center, and it has to be minimally disruptive to the existing environment.
The problem that you're going to run into with a clamp-on ammeter is that you can't actually clamp it over the entire power cable - if you do this, you'll read a zero-amp current. Assuming that you're dealing with single-phase power, you'd need to clamp over either the hot or neutral (I'm going to assume that there's little if any current going back down the ground) to get an accurate reading.
Most of the modern servers I've worked with allow you to monitor their power draw in real-time via their iLOM/ipmi controllers. Have you looked into this possibility?