I am wiring a UPS which shows on the one line it has regular power from the switchgear and then power from the ATs with battery back-up. The switchgear power is locked out from the battery side unless power goes down and then the ATS emergency power will power the batteries and close going to the load. The UPS states it can have one or 2 sources. What is the purpose of having both paths, it seems as if it could be done solely through the ATS because it’s power from the gear and emergency power in case of an outage. Let me know if I can clarify, it’s being wired per engineering but want to know the thought process behind it.
Ups wiring
- Thread starter Jnewell
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It sounds like you are describing a UPS with a bypass circuit. The main circuit powers the rectifier, inverter and charges the batteries. If a fault occurs in the main section of the ups it will switch to the bypass without interrupting the load. You can also switch to bypass manually for maintenance or troubleshooting.
Jeff
Jeff
petersonra
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UPS's are often more of a problem than power outages. You need to be able to bypass them for maintenance and testing, and when they fail.
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Some that are on-line all of the time (for power quality) will also use the bypass to provide for surge loading beyond the capability of the inverter.
RumRunner
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EPS is different from UPS.
UPS as the acronym implies means UNINTERRUPTIBLE while EPS means EMERGENCY.
(UPS) Uninterruptible Power Supply and (EPS) Emergency Power Supply.
UPS is always connected and the “switching” like you have stated in EPS, is NOT always connected.
Primary components of EPS are ATS, some power cells including solar combo/ batteries and portable generators etc.
UPS is mainly for data preservation where a drop in frequency, unstable power, or total lose of power. It is also seen in life saving/preservation as in operating rooms.
It is limited in its continuity of power sustenance unlike EPS
UPS doesn’t like or cannot tolerate momentary “blip” because electronics doesn’t pause. . . it wants power all the time for its processing routine..
DATA CENTERS require monitors that can tell that power failure is imminent-- and that allows technicians to properly shutdown the equipment.
Unintended or PANIC shutdowns are the curse of data centers.
Without proper backups-- power lose in data centers is devastating.
Although EPROMs can retrieve data in case of power loss-- but the application is not always practical and it is limited.
I mentioned the high-flown explanation (and a bit of a stretch) above in case some Computer Engineer is lurking in the background just waiting to jump me. Ha ha ha.
Emergency Power Supply is mostly used in Fire Alarms and Fire Suppression. . . it can tolerate momentary power lose.
You are asking for input …….based on thoughts process.
I hope the above spiel will serve that purpose.
Your explanation is tending toward EMERGENCY POWER SUPPLY. . . . not UNINTERRUPTIBLE POWER SUPPLY.
Yes, that’s what the super said. Thanks for the response.
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Actually, there are two fundamental types:
1. Standby/Backup UPS which charges battery from normal (POCO) power and starts its battery powered inverter and flips transfer switch on power loss. Most computer and other electronic instrument power supplies. Those power supplies can generally ride through an AC dropout of only a few cycles.
2. Dual Conversion UPS in which the inverter is constantly running off the constantly charging battery. There is no transfer switch and no startup delay. If the inverter output is synchronized to normal power when present, it is possible to close a bypass relay to handle surge loads on the output side. Not all dual-conversion UPSs have this fesature.
Russs57
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That is not how it see it.
Yes, there is the main UPS circuit from the ATS. Then there is a separate bypass maintenance circuit. This is a manual operation. You would have to open the switch/breaker for the ATS feed before closing the bypass switch/breaker. The UPS should have a static switch the can use the ATS power directly in the event of an overload or inverter failure. That is automatic and seamless as both sources would be in parallel to the load for a brief period.
Some UPS's will have the bypass breaker built in. That may come from a second circuit (better) or it may come from the only source (worst). To me, the best is an external breaker so the load could remain live if the UPS had to be replaced in it's entirety. It also lets you service/replace the ATS. Rather it is worth the extra cost is up to the risk assessment team.
Yes, there is the main UPS circuit from the ATS. Then there is a separate bypass maintenance circuit. This is a manual operation. You would have to open the switch/breaker for the ATS feed before closing the bypass switch/breaker. The UPS should have a static switch the can use the ATS power directly in the event of an overload or inverter failure. That is automatic and seamless as both sources would be in parallel to the load for a brief period.
Some UPS's will have the bypass breaker built in. That may come from a second circuit (better) or it may come from the only source (worst). To me, the best is an external breaker so the load could remain live if the UPS had to be replaced in it's entirety. It also lets you service/replace the ATS. Rather it is worth the extra cost is up to the risk assessment team.
RumRunner
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1
You can have different types of power backups that could mitigate the devastating effect of power dropouts. But their application varies.
In this case however, changeover is not being put into action because there will always be a gap in making the transfer—unlike keeping the UPS system connected 24/7.
As I have mentioned UPS is UNINTERRUPTIBLE which means power transition must be seamless.
When I designed network systems--I always made sure that seamless power is available to DATA CENTERS – and is given its utmost importance.
I don’t agree with your “ride through an AC dropout of only a few cycles”.
Maybe OK for ice cream factory-- not for DATA CENTERS.
In its design stage (network system) —it really doesn’t cost much to integrate a “monolithic” structure that doesn’t involve undesired gaps in supplying power.
In today’s environment –it’s no longer a big problem in providing UNINTERRUPTIBLE power.
Those being the availability of Hydrogen Power Cells and of course TESLA’s Power Wall Packs.
Silicon Valley’s semiconductor outfits are using Hydrogen Power Cells more than the TESLA.
And there is big rush of investors jockeying for their chance of getting a piece of the action.
In 2040 the projection is : some auto manufactures will no longer make ICE-powered cars. We'd be all dead by then to see that happen however.
It’s a heads up which probably would bring heated discussion.
So, if you or others specializing in ICE-- powered automobile. . . you will go down in history as: the titans that fizzled in time of the onset of battery power.
And now going back to the discussion:
During the processing and delivery of data (in computer speak)—communication between the server and the client doesn’t leave anything in between—it has to be precise.
One missing BIT is more than enough to register an error.
This is one consequence when you lose power even for a few cycles.
Keep in mind that when the server sends PACKETS and received by clients (in this instance members of this forum) these packets that were generated by the server (Mike Holt’s website) contain their unique identity—and packets must be precisely measured.
These include the length, number of segments, leading and trailing edges of the packet.
Momentary loss of power could result in mis-identified data packet that could also result in data being discarded. (thrown out)
If this event is not mitigated or resolved--the whole network would crash. Hence, the importance of UPS.
As a systems designing engineer—you had better have a good explanation to the company CEO as to why the system CRASHED.. . . or you’d be out-of-job tomorrow.
The few cycle dropout is what the computer engineer is concerned about and used to initiate a transition from the normal power source to the standby power. This is the instance monitored by the technical crew.
You can have different types of power backups that could mitigate the devastating effect of power dropouts. But their application varies.
In this case however, changeover is not being put into action because there will always be a gap in making the transfer—unlike keeping the UPS system connected 24/7.
As I have mentioned UPS is UNINTERRUPTIBLE which means power transition must be seamless.
When I designed network systems--I always made sure that seamless power is available to DATA CENTERS – and is given its utmost importance.
I don’t agree with your “ride through an AC dropout of only a few cycles”.
Maybe OK for ice cream factory-- not for DATA CENTERS.
In its design stage (network system) —it really doesn’t cost much to integrate a “monolithic” structure that doesn’t involve undesired gaps in supplying power.
In today’s environment –it’s no longer a big problem in providing UNINTERRUPTIBLE power.
Those being the availability of Hydrogen Power Cells and of course TESLA’s Power Wall Packs.
Silicon Valley’s semiconductor outfits are using Hydrogen Power Cells more than the TESLA.
And there is big rush of investors jockeying for their chance of getting a piece of the action.
In 2040 the projection is : some auto manufactures will no longer make ICE-powered cars. We'd be all dead by then to see that happen however.
It’s a heads up which probably would bring heated discussion.
So, if you or others specializing in ICE-- powered automobile. . . you will go down in history as: the titans that fizzled in time of the onset of battery power.
And now going back to the discussion:
During the processing and delivery of data (in computer speak)—communication between the server and the client doesn’t leave anything in between—it has to be precise.
One missing BIT is more than enough to register an error.
This is one consequence when you lose power even for a few cycles.
Keep in mind that when the server sends PACKETS and received by clients (in this instance members of this forum) these packets that were generated by the server (Mike Holt’s website) contain their unique identity—and packets must be precisely measured.
These include the length, number of segments, leading and trailing edges of the packet.
Momentary loss of power could result in mis-identified data packet that could also result in data being discarded. (thrown out)
If this event is not mitigated or resolved--the whole network would crash. Hence, the importance of UPS.
As a systems designing engineer—you had better have a good explanation to the company CEO as to why the system CRASHED.. . . or you’d be out-of-job tomorrow.
A large UPS will have means to terminate two circuits, the main and a bypass. The main powers the inverter, rectifier and battery charger then out to the load as an uninterruptible circuit. Should a fault occur with the inverter side the bypass circuit will pick up the load without interruption through a static bypass switch. The load is not protected by the UPS now. This static bypass can also be operated manually through the front panel, this will not interrupt the load. I would highly recommend an optional external bypass switch, this is a set of three circuit breakers that will allow you to route power to the load through the external cabinet without interrupting the load. Again the load in not UPS protected now. At this point the UPS can be shut down for repair, PMs or whatever. Generally, the main UPS circuit is fed by the ATS that has your alternate power source. This way, should you lose utility power the batteries will power the load until the alternate source fires up.If your are in a process that seldom shuts down this install is well worth the price.
Depending on how many 9's you need, this can be expanded by using two alternate power sources, two ups's ect.
Should your load be a data center, most servers have the option for two power supplies, each supply should be plugged into circuits form different sources. Ideally the sources will be separated as far as your one-line will allow. This allows panels to be shut down for PMs or to add circuits without interruption to the load.
GoldDigger is correct on the two types but I have only used dual conversion.
Depending on how many 9's you need, this can be expanded by using two alternate power sources, two ups's ect.
Should your load be a data center, most servers have the option for two power supplies, each supply should be plugged into circuits form different sources. Ideally the sources will be separated as far as your one-line will allow. This allows panels to be shut down for PMs or to add circuits without interruption to the load.
GoldDigger is correct on the two types but I have only used dual conversion.
RumRunner
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The above setup violates OCCAM’s RAZOR Rule.
Do not add anything more than necessary.
The simplest approach is always better than those complicated ones.
You can have the bypass, which requires both human intervention and technological wizardry--and of course the wonders of renewable source eg solar power, wind turbine and grid.
If you think that solar energy or wind power is the magic bullet—to provide power in the event of failure of power grid—what about in situation where failure occurred at night when solar power is virtually useless.
Batteries get discharged and wind becomes still or hardly moving to make to make it useful enough or much reduced energy output.
All of these power sources are like everything else. . . they don’t run indefinitely. They have to be shutdown for maintenance, recharging or repositioning in the case of SOLAR ARRAY. Although they can be done automatically, the need for them to shut down still remains a necessity.
This is when UPS is integrated into the design because of some sensitive loads like computers that needs to be on line always.
You mention two or more power sources that can be switched to bypass or switched from one source to another.
Does this scheme eliminate the possibility of momentary “BLIP”?
No can do.
Not only does this contribute to chances of breakdowns because you are adding more components that would increase those chances of breakdowns.
BYPASS SWITCH, RECTIFIER, BATTERY CHARGER and ATS.
Hello Murphy’s Rule.
A much better alternative that’s creating excitement among high tech observers and investors is; HYDROGEN POWER CELLS.
Elon Musk is not too enthusiastic about this.
Jeff Bezos is thumbing his nose. He is the prime investor.
These are now being use extensively in Silicon Valley. Also researches in Europe (Germany) as well as its use as a reliable source of power.
Deploying such energy source is as simple as ABC.
I say deploying is easy but the specialized manufacturing is not, however.
No transfer switches, no batteries and no solar power panels among other things.
Best of all-- it has no nasty by-product that will harm the environment.
Its only by-product is pure water and it will also run automobiles. The Toyota Mirai sold in California is Hydrogen powered.
When used as UPS all you need to do is replenish the hydrogen tank which raw material that is abundant and free. . . it's all around us.
No need for: ATS, RECTIFIERS or CHARGERS.
Hydrogen Power Cells do need maintenance too—but not as frequent as the others. Refueling is fast--about five minutes.
Compare that to battery charging that takes several hours.
Ensuring continuous operation can be done on- the- run, , , meaning no shutdowns.
Just like refueling aircraft in midair.
How does that grab you?
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Hydrogen power cells? Like fuel cells? As in the ones that use natural gas? Hardly immune to supply disruption and they have no place in discussion of a UPS.
The purpose of the bypass on a UPS is to keep the loads powered during maintenance or repair of the UPS, thats not overcomplicated, its good design practice.
The purpose of the bypass on a UPS is to keep the loads powered during maintenance or repair of the UPS, thats not overcomplicated, its good design practice.
RumRunner
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Study the concept in terms of its use as UPS.
Better still read this.
World-first home hydrogen battery stores 3x the energy of a Powerwall 2
To get off the grid with home solar, you need to be able to generate energy when the Sun's out, and store it for when it's not. Normally, people do this with lithium battery systems – Tesla's Powerwall 2 is an example. But Australian company Lavo has built a rather spunky (if chunky) cabinet that…
newatlas.com
That lavo thing is interesting, using an electrolyzer to make the hydrogen and a fuel cell to make the electricity. A bit expensive at $35k for 5kw of output. Looks too new for widespread adoption. And all this thing would do is replace the battery component of the UPS -you still need the rest of the UPS.....
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