[ARCHIVED THREAD] - Generators for Server Rooms (Page 1 of 2)
Posted: 6/2/2011 1:18:19 PM EDT
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The power went out 5:15 last night as I was about to head home.
Weather outside was fine. Upper 60s / Lower 70s; no major storms anywhere in the area. We have everything on UPS's with an hour minimum uptime. This is the 4th power outage in 2 years, none of them have been less than 4 hours. Talk to me about Diesel Genny's. |
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What about them? Just hook the gen up to the transfer switch and never worry about it again, unless you run out of fuel. I have a 500 kva gen powering 3 40kva ups units and 3 more 20 kva ups's with a 400 gallon tank. As it is loaded it will keep everything on for about 3 days with a full tank. |
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Military ones are getting surplused out now.
Mep-002 = 5kW Mep-003 = 10kW I think they've also got 15s, 30s, and 60s. You'd better have at least a deuce and a half to tow one, tho. I think my mep-002 weighs about 800 or 900 pounds. They're fairly cheap for how bulletproof and overbuilt they are. They are, however, extremely LOUD. Some come with a sound suppression system. Insulated cover and muffler. You could also take a deuce engine and couple a generator head to it. There's a company that actually sells turnkey gensets like that. LDT-465 is about 130hp max, unmodded. Then you could burn waste motor oil in it, for super cheap funtime electricity. |
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What about them? Just hook the gen up to the transfer switch and never worry about it again, unless you run out of fuel. I have a 500 kva gen powering 3 40kva ups units and 3 more 20 kva ups's with a 400 gallon tank. As it is loaded it will keep everything on for about 3 days with a full tank. I'll add to this that we get generators that are half of the rating that we would otherwise get. Then you get the equipment that will let you connect them together. Then you get three of the generators. That way one can go down without removing the ability to backup your facility. I will also suggest that you carefully look at the startup power needs of your cooling equipment. I've seen a facility where the chillers weren't put in correctly so on startup they drew 11megawatts each. So you would start them up and that would trip the generators taking you back to batteries. |
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Look into natural gas/propane units. Storage of diesel can have issues with moisture. True, but that brings in other problems. How reliable is the natural gas delivery? Will it be there when you need it? I've got a day of diesel on site with contracts to get as much more as I want with 1 hour notice. |
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Quoted: And dont forget to exercise them weekly and perform a load test eat least annually.Quoted: What about them? Just hook the gen up to the transfer switch and never worry about it again, unless you run out of fuel. I have a 500 kva gen powering 3 40kva ups units and 3 more 20 kva ups's with a 400 gallon tank. As it is loaded it will keep everything on for about 3 days with a full tank. I'll add to this that we get generators that are half of the rating that we would otherwise get. Then you get the equipment that will let you connect them together. Then you get three of the generators. That way one can go down without removing the ability to backup your facility. I will also suggest that you carefully look at the startup power needs of your cooling equipment. I've seen a facility where the chillers weren't put in correctly so on startup they drew 11megawatts each. So you would start them up and that would trip the generators taking you back to batteries. |
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There are plenty of dual fuel (natural gas/propane) options out there. So long as you have a supply, they are an excellent option for what you are looking for. Most newer generators come with automatic/weekly startups to keep the plugs clean and the generator running properly.
You can also get dual fuel in diesel/natural gas, or some even offer tri fuel. |
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And dont forget to exercise them weekly and perform a load test eat least annually.
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What about them? Just hook the gen up to the transfer switch and never worry about it again, unless you run out of fuel. I have a 500 kva gen powering 3 40kva ups units and 3 more 20 kva ups's with a 400 gallon tank. As it is loaded it will keep everything on for about 3 days with a full tank. I'll add to this that we get generators that are half of the rating that we would otherwise get. Then you get the equipment that will let you connect them together. Then you get three of the generators. That way one can go down without removing the ability to backup your facility. I will also suggest that you carefully look at the startup power needs of your cooling equipment. I've seen a facility where the chillers weren't put in correctly so on startup they drew 11megawatts each. So you would start them up and that would trip the generators taking you back to batteries. Testing with the correct type of load to match the power factor that you are drawing. |
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Quoted: Quoted: Look into natural gas/propane units. Storage of diesel can have issues with moisture. True, but that brings in other problems. How reliable is the natural gas delivery? Will it be there when you need it? I've got a day of diesel on site with contracts to get as much more as I want with 1 hour notice. Dont do this if you are in CA/earthquake country. after a big one all the nat gas will be off for weeks, then you are hosed. And there is no way i could store that much propane on site. Diesel is your only choice in CA, and they are trying to ban that as well. |
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Look into natural gas/propane units. Storage of diesel can have issues with moisture. True, but that brings in other problems. How reliable is the natural gas delivery? Will it be there when you need it? I've got a day of diesel on site with contracts to get as much more as I want with 1 hour notice. You can store natural gas on site too. Most cities have natural gas lines to most buildings and during most power outages the gas will keep flowing. Keep a tank for your reserve after that. If you're looking for uptime during a Katrina-type event, that might be more difficult to get resupply and diesel would probably be better. But if you're trying to maintain an office building for severe storm type conditions, natural gas will probably fit the bill nicely. |
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Call several of your local Gen Set / backup power companies and get quotes. They'll send a guy out to put something together for you. You'll also need an electrical contractor to handle the feeds in/out of your building etc. We put in a small 25kw (irrc) diesel unit a few years ago, it's self contained and sits on a tank of fuel. A maintenance contract with the vendor gets a truck out every month to top it off and make sure its all gtg. Ours exercises once a week for 30 minutes and then cools down/shuts off. eta: search google for "generator installation <your city name>" and you'll find someone. |
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Quoted: Quoted: Look into natural gas/propane units. Storage of diesel can have issues with moisture. True, but that brings in other problems. How reliable is the natural gas delivery? Will it be there when you need it? I've got a day of diesel on site with contracts to get as much more as I want with 1 hour notice. Dual propane/natural gas. This way you have options. While propane is about equal in price per MBTU to diesel, natural gas is about half that. Of course, you have to be there to switch fuels, it still gives you better options than diesel alone. In the sub 50 kW market, there are no dual fuel diesels, you are stuck with indirect injection diesels which are only slightly more efficient. Natural gas utility distribution systems store it in high pressure mains, regulating the pressure so there is usually a good supply inside the "city gate". If the utility is integrated, natural gas is used in summer months to fuel gas turbine generators and is bought at discount during shoulder months. They typically shoot for a quarter's worth of inventory or more. |
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We use a little Generac on natural gas. It'll run on propane too, and we have a valve in the feed line so we could run it off bbq tanks if we lost utility gas. We used to have a tank at our old location but zoning won't let us put one close enough to the building now.
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Quoted: Quoted: Look into natural gas/propane units. Storage of diesel can have issues with moisture. True, but that brings in other problems. How reliable is the natural gas delivery? Will it be there when you need it? I've got a day of diesel on site with contracts to get as much more as I want with 1 hour notice. They make large gas tanks.  |
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Caterpillar generators and asco transfer switches FTW. Kohler gennys and transfer switches are good too. Figure out if you need N+1 reliability. Size the generator to match. Get the biggest genny head that the selected engine size can run if its not too much of a price increase overall. Normally you want a decent load on a generator. 50% or more to prevent wet stacking. Most of the cost is tied up in time and materials. Its less labor to power whole existing panels than to pick and choose circuits and move them to a panel that will run on generator. You may find that the installation costs for upgrading the size of the generator and powering the whole existing panel is cheaper than buying a smaller genny and moving the existing circuits to it. Don't forget your cooling systems. CRACs in the server room and the chillers or dry coolers on the roof that may be fed from other panels. Also, putting a genny on the roof is a pain in the ass. You have to run piping up there to get the fuel to the genny. And diesel will eat roofing materials if there is a spill. Best not to locate them up there. Contract with TWO companies for diesel delivery at a moments notice. Hook a tank meter up to your alarm system so at minimum you will get a page when the tank is half full. Leave room for yourself to grow. And for the love of god do ALOT of research into finding a good electrical contractor that doesn't take shortcuts. Pay once cry once. -Foxxz ETA - Make sure to get the genny load tested (load banking). If its supposed to be able to do 125% output for 2 hours and then continue functioning at 100% afterwards have it tested on site to those specs. Also, if your AC systems aren't on UPS you need to make sure they will restart automatically after a power outage. Even if they do some will go through a compressor cycle which can take seconds to minutes depending on your unit. Can the server room deal with that AC downtime and can the AC catch up to the heat load? |
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If you can get natural gas in your area, they are usually cheaper to run, and you definitely never have to worry about refills / running low.
We had a midsize onan genset on our DC; it's basically just a big cummins engine that runs off natural gas instead of diesel. Wired that into the tri-phase UPS and, viola, all done. It would automatically start once a week to make sure everything was working, otherwise it was up to the UPS to tell it to come on, which it would do if the power went out and battery charge dropped below 25%. |
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I do a ton of generator work.
The diesels are far more reliable and powerful than the gassers. They are also more expensive. Water in the diesel fuel is a non-issue. If you have a large tank, I can filter and treat the fuel in just a few hours. Small tank......don't worry about it. Burn up your fuel and refill twice a year. Change your filters every year and try to keep the tank full in humid climates. Nat gas flow/pressure is hard to regulate and control when your loads change. And it takes longer to start gassers. Avoid going larger than 100Kw with a gasser unless your ok with the odd behavior that goes along with them. Propane has to have a properly sized fuel tank. Fuel lines need sized right, regulators need to be placed in the proper location. 90% of all gaseous generators have incorrect fuel systems installed by contractors. You also need to make sure that the generator is a bit oversized for your UPS load (compared with regular building type loads) and can handle the nasty harmonics and THD that a cheap UPS may have. Good UPS's can handle it when a gensets voltage, Hz is off a little or droops some during load changes. Bad UPS's can't. I get alot of calls about UPS's not accepting generator voltage because the weak gas genset droops when the UPS applies load. A good UPS will deal with that and wait for the generator to catch up. Diesels get along better with UPS's, unless you only need 25Kw and just bought a 100Kw gasser. As long as you way oversize the gasser you'll usually be ok. Basicly it's cheaper to build a UPS that can only handle perfectly clean power. What kind of voltage, amp load, are you looking to power up? |
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We use a little Generac on natural gas. It'll run on propane too, and we have a valve in the feed line so we could run it off bbq tanks if we lost utility gas. We used to have a tank at our old location but zoning won't let us put one close enough to the building now. How many gallons/hour does that generator consume on propane, and for what kW output? I'm envisioning a data center running off of BBQ tanks and some poor lackey changing tanks every 15 minutes 
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OK, let me clarify my posts with one thing. You have to decide how critical your loads are. Is the generator there for convenience or do you have to pay out a million dollars for every hour of downtime? That will let you know what to shoot for. Very un-critical. We will not be powering workstations. Server room is about 200 sq ft. Houses two mostly empty racks, holding a total of 12 servers. I am thinking of one genny with enough power to run the A/C and the servers. With enough fuel on site to run for 48 hours + service maint / testing. I am not sure of the A/C unit size. |
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We use a little Generac on natural gas. It'll run on propane too, and we have a valve in the feed line so we could run it off bbq tanks if we lost utility gas. We used to have a tank at our old location but zoning won't let us put one close enough to the building now. How many gallons/hour does that generator consume on propane, and for what kW output? I'm envisioning a data center running off of BBQ tanks and some poor lackey changing tanks every 15 minutes We've never had to do it, but I think I'm probably the lackey that would be in charge of tank swapping.
We only have a few dozen servers, it's not some huge data center. |
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Quoted: Quoted: We use a little Generac on natural gas. It'll run on propane too, and we have a valve in the feed line so we could run it off bbq tanks if we lost utility gas. We used to have a tank at our old location but zoning won't let us put one close enough to the building now. How many gallons/hour does that generator consume on propane, and for what kW output? I'm envisioning a data center running off of BBQ tanks and some poor lackey changing tanks every 15 minutes At full power, figure on 0.75 pounds per kW-hour. With no load, about 0.25 pounds per kW-hour, based on maximum. Ideally, your load should be between 50-75%. Standard grill tanks are 20 pound capacity. |
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Quoted: Quoted: Look into natural gas/propane units. Storage of diesel can have issues with moisture. True, but that brings in other problems. How reliable is the natural gas delivery? Will it be there when you need it? I've got a day of diesel on site with contracts to get as much more as I want with 1 hour notice. Lived in a hurricane zone all my life in LA and TX. Been thru Andrew (no power for 21 days), Katrina (no power for 10+ days), several smaller outages of a few days and in 1997 we had a straight line windstorm where we were without power for 7 days and not once in that entire time have I been without natural gas. |
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What about them? Just hook the gen up to the transfer switch and never worry about it again, unless you run out of fuel. I have a 500 kva gen powering 3 40kva ups units and 3 more 20 kva ups's with a 400 gallon tank. As it is loaded it will keep everything on for about 3 days with a full tank. I'll add to this that we get generators that are half of the rating that we would otherwise get. Then you get the equipment that will let you connect them together. Then you get three of the generators. That way one can go down without removing the ability to backup your facility. I will also suggest that you carefully look at the startup power needs of your cooling equipment. I've seen a facility where the chillers weren't put in correctly so on startup they drew 11megawatts each. So you would start them up and that would trip the generators taking you back to batteries. It's like RAID for electicity .... BRILLIANT! |
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Quoted: Quoted: OK, let me clarify my posts with one thing. You have to decide how critical your loads are. Is the generator there for convenience or do you have to pay out a million dollars for every hour of downtime? That will let you know what to shoot for. Very un-critical. We will not be powering workstations. Server room is about 200 sq ft. Houses two mostly empty racks, holding a total of 12 servers. I am thinking of one genny with enough power to run the A/C and the servers. With enough fuel on site to run for 48 hours + service maint / testing. I am not sure of the A/C unit size. same setup as us , we have natural gas generac but i forget the size . its 100% reliable so far . |
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We use a little Generac on natural gas. It'll run on propane too, and we have a valve in the feed line so we could run it off bbq tanks if we lost utility gas. We used to have a tank at our old location but zoning won't let us put one close enough to the building now. How many gallons/hour does that generator consume on propane, and for what kW output? I'm envisioning a data center running off of BBQ tanks and some poor lackey changing tanks every 15 minutes Propane gas generators require large tanks. The liquid turns to gas at the surface level of the fuel. The larger the surface area, the more efficient the flow. So large long tanks are handy. And you can't overfill them, since the tanks are round, you have more surface area at 60% full than you would at 90%. Generac is the worst big name stand-by generator system. Stick to Kohler, Cummins (at least their higher end units), and Katolight. |
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What about them? Just hook the gen up to the transfer switch and never worry about it again, unless you run out of fuel. I have a 500 kva gen powering 3 40kva ups units and 3 more 20 kva ups's with a 400 gallon tank. As it is loaded it will keep everything on for about 3 days with a full tank. I'll add to this that we get generators that are half of the rating that we would otherwise get. Then you get the equipment that will let you connect them together. Then you get three of the generators. That way one can go down without removing the ability to backup your facility. I will also suggest that you carefully look at the startup power needs of your cooling equipment. I've seen a facility where the chillers weren't put in correctly so on startup they drew 11megawatts each. So you would start them up and that would trip the generators taking you back to batteries. It's like RAID for electicity .... BRILLIANT! As long as the hardware that keeps the frequency output in sync is working, yes. Otherwise, not so much. |
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Quoted: Quoted: OK, let me clarify my posts with one thing. You have to decide how critical your loads are. Is the generator there for convenience or do you have to pay out a million dollars for every hour of downtime? That will let you know what to shoot for. Very un-critical. We will not be powering workstations. Server room is about 200 sq ft. Houses two mostly empty racks, holding a total of 12 servers. I am thinking of one genny with enough power to run the A/C and the servers. With enough fuel on site to run for 48 hours + service maint / testing. I am not sure of the A/C unit size. Take your server power load and add 50% for cooling load. More if you are in a warm climate. |
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You can use parallel gear to parallel 2 gensets together. Some gensets have this ability built in now, but I still prefer parallel gear.
Or you can use 2 auto transfer switches and no parallel gear. One switch is in series with the other. If the primary generator fails, then the switch on the load side of the first switch will transfer onto the secondary genset. Kind of a poor mans parallel gear. |
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The power went out 5:15 last night as I was about to head home. Weather outside was fine. Upper 60s / Lower 70s; no major storms anywhere in the area. We have everything on UPS's with an hour minimum uptime. This is the 4th power outage in 2 years, none of them have been less than 4 hours. Talk to me about Diesel Genny's. quit fucking around and go natural gas. cummings will set you up. and WTF are you doing with less than 4 hours ups runtime? hopefully nothing inportant. |
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Caterpillar generators and asco transfer switches FTW. Kohler gennys and transfer switches are good too. Figure out if you need N+1 reliability. Size the generator to match. Get the biggest genny head that the selected engine size can run if its not too much of a price increase overall. Normally you want a decent load on a generator. 50% or more to prevent wet stacking. Most of the cost is tied up in time and materials. Its less labor to power whole existing panels than to pick and choose circuits and move them to a panel that will run on generator. You may find that the installation costs for upgrading the size of the generator and powering the whole existing panel is cheaper than buying a smaller genny and moving the existing circuits to it. Don't forget your cooling systems. CRACs in the server room and the chillers or dry coolers on the roof that may be fed from other panels. Also, putting a genny on the roof is a pain in the ass. You have to run piping up there to get the fuel to the genny. And diesel will eat roofing materials if there is a spill. Best not to locate them up there. Contract with TWO companies for diesel delivery at a moments notice. Hook a tank meter up to your alarm system so at minimum you will get a page when the tank is half full. Leave room for yourself to grow. And for the love of god do ALOT of research into finding a good electrical contractor that doesn't take shortcuts. Pay once cry once. -Foxxz ETA - Make sure to get the genny load tested (load banking). If its supposed to be able to do 125% output for 2 hours and then continue functioning at 100% afterwards have it tested on site to those specs. Also, if your AC systems aren't on UPS you need to make sure they will restart automatically after a power outage. Even if they do some will go through a compressor cycle which can take seconds to minutes depending on your unit. Can the server room deal with that AC downtime and can the AC catch up to the heat load? This guy knows his stuff! Never put a genset on the roof. Oil weeping from the rear main will eat the roof. Maintenance costs will go through up! I hate heights. And it gets real windy cold up there, block heaters can't keep up in the winter sometimes. I load bank to 100% of max rated genset output. then I make sure that the genset can handle a full block load. dropping and removing load completely. Lots of good good smoke. It's good to loadbank 2hrs every year so that you can safely run diesels as low as 30% load. I've found that Cats can't handle full block loads nearly as well as Kohler or even Cummins. CAT was one of the lobby groups that had influence on the old load bank test code for hospitals where code allowed 25% then 50% then 80% to pass a load bank test. I'm way harder on equipment, i want to see what it can do. I drop a simulated building load on the genset for 15 min, then go straight to 100%. Then I full block load a few times and try different load levels to see if I can trip up the DVR or Gov. |
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Talk to an electrical engineer in your area that does this kind of work. Arfcom is brilliant and most of the comments here are spot on, but you're not going to get a complete design from the internet. Oh shit.......... Get an engineer to do a load survey. Complete with THD, inrush, etc. etc. But do not under any circumstance allow the engineer to spec the gensets cut sheet. He'll allways spec something too small. Engineers cut things close and play by the book. But generator companies know thier equipment well and know that sometimes a little more is going to be needed to ensure reliability. Angry customers can kill a little generator company by word of mouth quickly. The engineer needs to determine what he needs a genset to do. Then he needs to step aside and let the sales department of a local Kohler/Cummins/Katolight distributor decide which genset to quote that meets the engineers load demands. Then he either OK's or denies that quote. (often for a much larger piece of equipment than he originally thought about) Electrical engineers aren't really allowed inside the genset housing or ATS. They need to tell a generator co. what their requirements are and then let the generator company meet them. |
One of the projects I want to get done this summer is to rewire the diesel pumps for the huge Cat gen set at work. The generator is on the roof. The diesel tank is in the basement. They wired up the pump that moves the diesel up to the generator so that it runs on grid power. There is no provision to pump fuel using generator power. |
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One of the projects I want to get done this summer is to rewire the diesel pumps for the huge Cat gen set at work. The generator is on the roof. The diesel tank is in the basement. They wired up the pump that moves the diesel up to the generator so that it runs on grid power. There is no provision to pump fuel using generator power. Just move the pump feed wires to the load side of the ATS or an panel on the load side of the ATS. |
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I am running a 50KW natural gas on municipal service. We have enough on it that we need to upgrade soon. It keeps around 50 servers up access control and some lighting. We don't have it running out main cooling just the backup fans. eta its a Onan and been great maintenance has it serviced twice a year. local dealer dose it. If you can fine a stable major local dealer thats full service its a great thing to have.
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Talk to an electrical engineer in your area that does this kind of work. Arfcom is brilliant and most of the comments here are spot on, but you're not going to get a complete design from the internet. That's true. I would like to offer some other suggestions to think about: 1. You will probably not use up the diesel. That means that it will sit a while. That means that it needs to be delivered dosed with a biocide or you need to dose the fuel, or plan on draining the tank periodically and putting in fresh fuel. It would be a very good idea to add some large filters, in parallel, allowing hot swaps, with pressure diff guages to make sure that you stay running. This is pretty cheap, but you need to have a solid diesel guy do it when you install this. 2. Make sure that you don't have to go up stairs to get to the unit. It sucks hauling 55 gallon drums up diesel up the stairs. 3. Temperature rise –– know it, understand it, and that will explain a lot of cost differences. You get what you pay for here. 4. Standby vs. prime vs. continous –– how long could you potentially need this to run? 5. The chiller deal was already mentioned, but I will mention it again and ask if your security system and PBX is on the same curcuit? So that you can dial out if the power is down? Do you have a separate analog line for the security system? People always miss that ... 6. Add a centrifugal pre-cleaner for the air filter –– it keeps a lot of junk out. Some operate with air pressure alone (Centri units are cheap and work fine). 7. Add a bypass filter of some kind for the oil. For light use, a media as opposed to centrifugal unit works better because it traps water. A centrifuge won't. 8. Make sure that it comes with a coolant filter. 9. Remote monitoring of the generator is nice. 10. Don't put it where rain will always fall on it from the roof. You would think that people wouldn't do this, but they do. 11. Make sure that if it is at ground level or close it is not in a low spot. Similarly, if it is at ground level or close to it, make sure that a truck can pull up to it easily to refuel. And finally, make sure that you have big steel pipes set in concrete around it so that the truck cannot back into it easily after fueling. 12. Emissions doesn't usually let systems these days vent the case to the environment, but if you get an old one, don't vent this right to the pad around the genset –– you WILL slip and fall. Vent it into a bucket full of kitty littler, out of the rain. Your knees will thank you. |
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One of the projects I want to get done this summer is to rewire the diesel pumps for the huge Cat gen set at work. The generator is on the roof. The diesel tank is in the basement. They wired up the pump that moves the diesel up to the generator so that it runs on grid power. There is no provision to pump fuel using generator power. Just move the pump feed wires to the load side of the ATS or an panel on the load side of the ATS. Try to make sure that the basement tank vents well over the highest level that you could see flooding. A dessicant cap (of you are in a humid climate) will keep a lot of water out of the fuel. |
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Look, my advice is this.
Call a local company to do the work. You can get good ideas and directions here but you'll want an onsite survey done to determine loads, generator placement, pouring of a pad, wiring it up and all that other shit. We use a big fucking Cat genny thats a 125kw unit if I recall. Has all the auto start, auto transfer switch auto test blah blah blah in it. Nice thing is you can cut your UPS needs to something on the order of 5 minutes if you want to free up some space in the server room too. |
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Talk to an electrical engineer in your area that does this kind of work. Arfcom is brilliant and most of the comments here are spot on, but you're not going to get a complete design from the internet. Oh shit.......... Get an engineer to do a load survey. Complete with THD, inrush, etc. etc. But do not under any circumstance allow the engineer to spec the gensets cut sheet. He'll allways spec something too small. Engineers cut things close and play by the book. But generator companies know thier equipment well and know that sometimes a little more is going to be needed to ensure reliability. Angry customers can kill a little generator company by word of mouth quickly. The engineer needs to determine what he needs a genset to do. Then he needs to step aside and let the sales department of a local Kohler/Cummins/Katolight distributor decide which genset to quote that meets the engineers load demands. Then he either OK's or denies that quote. (often for a much larger piece of equipment than he originally thought about) Electrical engineers aren't really allowed inside the genset housing or ATS. They need to tell a generator co. what their requirements are and then let the generator company meet them. That's fair –– I have usually seen something 30% larger from the genset companies. I have tried to spec larger than that. I don't miss those fights. One thing that EEs are good for here is doing a power survey that will tell you if your local power is really bad. It often is, and k-rated transformers are cheap, and that works better for the whole building. |
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Make damn sure your genny will also support your cooling in the critical areas.
I took care of a server depot that was overheating within an hour of losing power because they only spec'd the genny to support the servers, not the cooling. Nothing I could do for them and with the temps approaching 100*F they were forced to shut down anyways. |
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The power went out 5:15 last night as I was about to head home. Weather outside was fine. Upper 60s / Lower 70s; no major storms anywhere in the area. We have everything on UPS's with an hour minimum uptime. This is the 4th power outage in 2 years, none of them have been less than 4 hours. Talk to me about Diesel Genny's. over the years i have worked for several companies that used computers as the core of the business and had backup power options. first company had diesel generators and a very large bank of batteries. this ran mainframe computers and network gear. generator was industrial strength. second company, a bit smaller but had a bank of batteries with a somewhat large generator that ran off natural gas. at the time the second company started, it was almost impossible to get approval for an in ground diesel storage tank. my guess, the best option is natural gas or propane if you cant get natural gas where you are. im about to install a whole house generator, 20 to 25 kw. it will run off natural gas. i work out of my house and do computer work. the backup generator will make things easier. im slowly turning my house into a data center. a friend has a house way out in the woods, down a dirt road. he runs a data center off a t1. his 'gas' is propane. he has a backup generator to run his 'data center'. it runs off propane like his heat. natural gas or propane is the way probably. you can rent industrial diesel generators. large towable units. some places will have this as their backup plan. |
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I've found that Cats can't handle full block loads nearly as well as Kohler or even Cummins. CAT was one of the lobby groups that had influence on the old load bank test code for hospitals where code allowed 25% then 50% then 80% to pass a load bank test. This has been my experience. I have been more impressed with Cummins. |
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I like Kohlers the best. But their outdoor weather housings and box covers are nowhere near as sturdy as CAT or Cummins.
Kohlers have good Marathon generators made in the US. CAT and Cummins use China or India generators. And you have your choice of MTU or Mitsubishi engines in the really big Kohler stuff. The medium sized ones have beefy Volvos. The 16L I6 Volvo is good for 600Kw with twin turbos. Small stuff is John Deere. Overall a pretty good engine lineup. The big Mitsu's are pretty much copies of the big Caterpillar engines. Big iron, simple design. But better throttle response. The downside is the Mitsu cooling system is usually a bit more complex than CATs ideas. The MTU's are in a class of their own. Nothings quite like those. Sometimes simple, sometimes really complex. MTU is more often put into flashier ships than the crab boats CAT and Mitsu would usually be in. |
