View Full Version : how much to test new DC power wiring?
12-22-2006, 05:05 AM
When you install new electrical gear in your datacenter (circuit breaker panels, PDUs, transformers, UPSes, etc.), how much testing do you do before you put servers on the power source?
I have a new electrical infrastructure in a datacenter expansion. One large electrical contractor has suggested that I should put a load bank onto every new PDU, bring the PDUs and the UPSes to 80% load for a half-hour, and thermal-image every electrical fitting looking for hot spots. But the cost for the service is high (about 5% the cost of the electrical install itself).
Another electrical contractor says I should be fine with just getting "base-line" thermal image readings of everything soon after the install (at low load), then re-image all wiring semi-annually to watch for possible future problems.
The UPS reseller suggests that their commissioning and preventive maintenance on the UPSes should be enough. And they sell PDUs, so hopefully they should know :) . How much stress, testing and measurement do you do on a new UPS, PDU or sub-panel before you decide that it's "good enough"?
12-26-2006, 01:24 PM
I would suggest that your first electrical contractor is correct. In fact, he probably doesn't go far enough. Load test everything you can for at least 4 hours. You may want to take advantage of the heat generated by the load banks to test your HVAC system.
Once you are satisfied with the results of the load bank/thermal imaging testing, move on to operational testing and integrated systems testing (IST). Here are a few ideas;
1. Battery run-down test. Open the UPS input breaker while the UPS is at 100% rated capacity. Does the battery last as long as your UPS reseller told you it would? See IEEE testing standard 450 (wet cells) or IEEE 1189 (VRLAs)
2. UPS transfer tests. Transfer to UPS internal bypass while at rated capacity, transfer back. If you can do this with a transient recorder on the output of the UPS you should. Do the same with the external bypass if you have one.
3. Static transfer switches. If you have these as part of your infrastructure, transfer from Source 1 to Source 2 and back at rated capacity.
4. Generator and ATS tests. Simulate a utility failure. Watch the generator start and verify that the ATS switches to generator. Use a stopwatch, <10 seconds is good. This test will also reveal compatibility issues between the UPS and generator. These problems are common and the time to find out you have one is not during an actual utility failure. If you have the transient recorder hooked up, make sure that this test has no effect on the quality of power at the UPS output.
5. Get creative. What other events can you simulate that may actually occur IRL? Give your infrastructure a serious workout.
For many people, the success or failure of their business (and their career) depends on these systems operating as they should in an emergency. I say test them until you know that they are dependable.
Yes, this testing can be expensive. However, compare the cost of testing vs. the cost of one hour of unscheduled downtime. (If you donít know what an hour of downtime will cost your company, you really should.)
One last thing, this is very specialized work and it may be a good idea to hire a professional commissioning agent. There are a number of good companies that can write testing procedures for you, perform the testing or both.
10-22-2010, 09:05 PM
I am a commissioning agent for an engineeering firm that works with data centers. We can assist you with your needs and taylor a commissioing plan for you. From writing a plan and tests, to managing a full data center commissioning process that would include a subcontracted thermographer and establising baseline trending. If you have a budget, we can offer services within your budget.
11-22-2010, 08:27 AM
hey view this video on the link:
01-11-2011, 02:18 PM
Also, I will suggest going with as dhampton said, outsourcing is best thing with this issue, as reliabilty will play major role in this, also there insurance cover if they did something wrong.
02-10-2011, 03:34 AM
The success or failure of their business depends on these systems operating as they should in an emergency. I say test them until you know that they are dependable.Yes, this testing can be expensive. However, compare the cost of testing vs. the cost of one hour of unscheduled downtime.
Roller Blinds (http://www.tradeblinds.com/)
Blackout Roller Blinds (http://www.tradeblinds.com/)
vBulletin® v3.8.7, Copyright ©2000-2013, vBulletin Solutions, Inc.