Five Things I Love About My DRUPS
By David Johnson
‘How do I love thee? Let me count the ways.’ It was not Shakespeare, but the poet Elizabeth Barrett Browning who penned that now famous line almost 150 years ago, and the words still ring true. But is data center equipment applicable to a love like no other?
It may sound strange, but Diesel rotary UPS (DRUPS) are not ordinary machines. DRUPS systems do offer some charming qualities that people like myself find irresistible. So, to the depth and breadth of my soul, let me count the five ways to admire DRUPS offerings.
We all want relationships to last, so at the top of the list of things to admire about a diesel rotary is the fact that it lasts – a very long time. While the usable life cycle is 30 years (as opposed to the 15-year standard from the batteries), today there are diesel rotary units still in service that were installed in the 1960s.
Even if the love only lasts 30 years, most would agree that is a pretty good run for the investment. Since the machine is constructed from tried-and-true mechanical components like motors, rotors, and generators, it will last as long as it is properly maintained.
Unlike that person you dated who came with a lot of boxes and furniture – and maybe some baggage to boot – a diesel rotary system is designed to fit in tight spaces, and doesn’t mind sleeping outside. Unlike a high-maintenance, battery-based proposition, DRUPS is something you can fit into your life.
Static-based systems require dedicated rooms with sophisticated mechanical controls and monitoring systems, all of which consume space and maintenance dollars. Rotary? It fits within the space you’ve got, and doesn’t demand special treatment.
Like the Shakespeare/Browning mix up, there are many things attributed to the more famous party that simply aren’t true. One of those misconceptions is the idea that static systems are less complicated electrically than rotary. But a careful look at the one-line diagram of both systems proves that rotary is simpler.
In a study of comparable 3 MW UPS systems, the static system requires a minimum of 12 input and output breakers to support the critical bus. Rotary? A mere three. Fewer breakers mean fewer single points of failure, which translates into less heartache down the road.
All Loads are Created Equal
When it comes to the UPS-supported loads, we all assume that this will be an IT only affair. But if you could support other systems besides computer loads, wouldn’t it change your thinking about data center design? Of course it would.
Part of the joy that comes from a relationship with diesel rotary is that I can put motor loads from my mechanical system on it and never, ever be concerned about thermal storage systems, complicated controls schemes, or thermal runaway. Now that’s a critical advantage.
Low Total Cost of Ownership
Of all of the things that make diesel-rotary systems special, I will shamelessly admit that the qualities mentioned so far make them a pretty cheap date. Call me shallow, but there is an economic side to any relationship – this is no different. And as it turns out, my diesel rotary system is the best deal both in terms of up-front cost, and also for the long haul.
No air conditioning bills, 10-year bearing overhauls, and better efficiency all contribute to a 30 percent lower operating cost. I have to say I am looking forward to looking back at a low TCO on our 30th anniversary.
Who knows, maybe we will decide to do it all over again.
David Johnson is Director of Business Development for Hitec Power Protection, Inc., a global technology leader in dynamic UPS systems for the supply of uninterruptible, continuous, and conditioned power to mission critical applications.