vtsnowedin wrote:Every water supply plant and every sewer works I have ever worked on has a nice big back up generator or generators set up with sufficiently large fuel tanks to run the facility completely for at least two weeks. If those tanks can be resupplied they could run for years if needed but the cost would be higher then grid supplied electricity. The only generators having a higher priority for fuel deliveries are those at hospitals.
Are you telling me managers in the UK have not been at east that prudent after the experiences of the World wars?
I once worked for a mega computer firm with serried ranks of on-line machines covering maybe an acre of floor.
Two huge diesel backup generators lurked in a big building outside the main hall. Battery backup supported the site for the time the gennies needed to start.
Power cut ... er, ummm ... the sound of silence ...
vtsnowedin wrote:Every water supply plant and every sewer works I have ever worked on has a nice big back up generator or generators set up with sufficiently large fuel tanks to run the facility completely for at least two weeks. If those tanks can be resupplied they could run for years if needed but the cost would be higher then grid supplied electricity. The only generators having a higher priority for fuel deliveries are those at hospitals.
Are you telling me managers in the UK have not been at east that prudent after the experiences of the World wars?
I once worked for a mega computer firm with serried ranks of on-line machines covering maybe an acre of floor.
Two huge diesel backup generators lurked in a big building outside the main hall. Battery backup supported the site for the time the gennies needed to start.
Power cut ... er, ummm ... the sound of silence ...
I have experienced very similar circumstances, in slightly smaller but still important premises.
I have little faith in standby generators unless maintained by myself, or by a specialist and overseen by myself.
UPS systems also.
It is a standing joke among battery vendors, that UPS batteries are normally replaced just AFTER the power cut against which they did not protect.
"Installers and owners of emergency diesels must assume that they will have to run for a week or more"
That is why modern systems exercise themselves weekly. This involves a built in clock and computer cutting off the mains power which trips (if working properly) the engine to start with the aid of it's batteries (if properly charged) and then supply power to the facility long enough to recharge the engines battery then bring the mains power back on line which signals a shut down. Any failure trips flags and warning lights that are difficult to remain unnoticed. It is a common system varying only in size to match required loads and even many house backup generators have them. The house my daughter and her husband bought in Maryland had such a system in place which added to the appeal of the property. It hums away for about twenty minutes every Wednesday at noon.
I worked for a company that used a Tandem TXP mainframe. Every transaction was performed by two processors, with a third watching the results to make sure there were no errors. The architecture was as fault tolerant as could be made, every card was duplicated, every psu, even the cables to users desks went to each floor-box via different routes, north and south risers. Naturally the power was supplied by twin supplies, backed up by twin UPS and twin generators.
Unfortunately the message didn't get to the guys who installed the aircon for the server rooms, because they weren't on the UPS. First time the power failed the rooms overheated and the Tandems executed "Die Nicely" and shut down. Oops.
Catweazle wrote:I worked for a company that used a Tandem TXP mainframe. Every transaction was performed by two processors, with a third watching the results to make sure there were no errors. The architecture was as fault tolerant as could be made, every card was duplicated, every psu, even the cables to users desks went to each floor-box via different routes, north and south risers. Naturally the power was supplied by twin supplies, backed up by twin UPS and twin generators.
Unfortunately the message didn't get to the guys who installed the aircon for the server rooms, because they weren't on the UPS. First time the power failed the rooms overheated and the Tandems executed "Die Nicely" and shut down. Oops.
Random anecdote: we had a water pump fail on a water cooled IBM.
IBM flew the £50 replacement plus an engineer immediately from Switzerland via helicopter. That was in the days when service was part of the leasing package. Of course, they filmed the whole thing for use as marketing PR!
