Видео

They’re health and safety officer mandates it? But I agree, only our electricians suit up if they are working on live boards where you can literally reach out and touch the 800 amp bus bars…

You bypass the batteries internally in the UPS, then parallel bypass around the UPS through a bus. Then open the internal bypass within the UPS.

Be greater to see barricades and signage

We call it a hot suit. And yes, if something goes wrong inside that switch gear At worst you lose a limb, die, or have all of your skin combust and melt off into a puddle on the floor. And even the suits don’t protect someone fully. Also, the vaporized copper from an arc fault can be inhaled. So Yea hold your breath when you flip breakers :)

You'd love bitcoin mining farms 😉

@@tjmooney4181 I know i would😉

Each has their own expertises. Do these data center workers for example know what goes into operating a nuclear power plant? I doubt...

@@Aomicplane Its interesting that a lot of data center workers worked on some type of nuclear stuff in the military, and then they transitioned to data center engineering.

because when switch is switched on you realy never know what will happen. teoreticaly switch should handle maximum shortcircuit current, but poorly maintained switch or wrongly designed switch/cabinet (or shortcircuit in strange place) and explode can happen. equwalent of shortcircuit in this scenario will be explosion of granade.

ruclips.net/video/PO6see7_ODY/видео.html

@@prjk7339 Well yes, I agree. But isn't it closed cabinet ? And how can short circuit happen apfter installation test, and regular monthly tests ? Or can this happen only in USA ?

@@robimaren3247 don't know how it is in USA but i know you have lower voltagest so to have same power current increases.the higher current the more sophisticated switch, bigger wires diameters and shortcircuit currents. Also you see only cabinets. But how to enter to cabinet with wires/rails? Often this is weak point used by fluids/animals. Also bad connections/wrong technology can cause heating/melting/shortcircuit. During normal operation it is rare event. Most common it happens during maintance/test/brakedown often by peoples in stress, lack of procedures. Also peoples dont realize that switches have limited numbers of switching actions (switching current dependant, and it is hard to aproximate how broken connection inside switch are)

It protects them from dangerous arc flashing

This! There's no need for 40 cal suits during an ATS open transfer if all enclosure doors are closed. The enclosure is DESIGNED to withstand an arc flash event by directing the flash behind the cabinet.

@@shortattentionspangarage1312it is a closed transition as both utility and generator are active sources at the time of the switching

I would guess as a just in case. Without running backup power, any disruption to utility would bring the place down.

Generators are more trustworthy than utility power.

The maintenance bypass is downstream from the ATS so you could send utility power through the maintenance bypass if utility was selected on the ATS. However utility power is not considered reliable so before that operation takes place the ATS selects the generator source.

that diagram is very poor, symbols are not conventional, but they show the load transferred from UPS modules to "static bypass" cabinet (operation done by UPS to transfer to its internal bypass), then its transferred to "maintenance bypass" (performed by closing external bypass breaker on switchgear). At the end the load wasnt feed by utility because UPS was transferred to generator then placed in bypass.

What do you mean "closed transition"? Utility and generator breakers closed at the same time for a second during transfer?

The 40cal suits are safety theater. They're not working on exposed an exposed bus. Honestly they expect people to suit up in an emergency like an ATS failure?

I currently work for NAVFAC UPS Shop. Looked like a Powerware 9390 UPS in the video. Everything is PLC ran now. Automagic! hahaha

MVP

It is referring to a oneline diagram of the system not that the system is online.

@@meoutdoors6106 shows how much this guy knows above your comment lmao

RUclips is drunk

same

All I watched was one ups video 3 days ago

@@TRC98 Watches one video YT: OH WOULD YOU LIKE MORE!??? HERE YOU GO! OH YOU LIKE WATCHING THE SAME VIDEO ONCE OR TWICE? HOW ABOUT 10 TIMES IN A ROW!

Same. But I was searching for these kind of stuff.

I don't think you should look at them as doing each their redundancy, but rather that to supply enough power for everything, you need both, at least if you want it to run within the time-window for testing.

I'm thinking they are both separate. Ex: UPS-1 is doing one row of racks, and UPS-2 is doing the other row. Though I suppose they could engineer it where they can transfer load around in order to have more redundancy.

Its for reliability. Running on one UPS at double load is a single point of failure. Running on multiple parallel gens is not.

Arc Flash suit

Because this can happen if something is wrong: ruclips.net/video/6hpE5LYj-CY/видео.html You don't want to be anywhere near an arc flash.

@@Manawyrm Thats pretty scary, whats even more scary is that the workers didnt wear gloves with their suits.

It's a arc flash suit and some electricians will say its the difference between an open casket and a closed casket funeral if your not wearing one.

@@Manawyrm arc flash is ticket to heaven don't buy it early 😂

From my experience, as you are taking the UPS (batteries specifically) offline, if the utility were to fail, generators would not be ready instantly as they have a warm-up/spin-up time. Normal operations if the utility were to fail, batteries would provide enough power until the generators became operational. With generators operational, you have a second power option with utility. Always have two active forms of power.

@@NathanChan40 Thanks for the answer. In my area there's a lot of hydro and pump hydro (excess power) and I haven't ever experienced a black out, however when working in isolated industry I saw a few gensets releasing their inner smoke, hence my question.

They have no control over the grid, but some level of control over their generators. As Nathan Chan has said, it takes a long time for a generator to startup and take the load. The bigger the generator, the longer it takes. If the UPSes are bypassed, and the grid fails, you want the generators to already be spinning and in sync. Even 'tho they aren't on grid, the PLC is keeping the generators in sync with the grid; should the need arise, they could go back to grid-only in milliseconds, without dropping the load.

@@ml9849 There's loads of hydro power in my area as well, but that doesn't help you when a tree falls into a power line or a drunk driver takes out a utility pole

It's more reliable as they will have multiple generators they can sync together so don't have to worry about grid going down.

Explain more! This sounds really interesting. What can happen in these situations?

Oh that's nothing. When you reset and the circuit breaker starts to eat itself due to malfunction. Ive seen that

I imagine they only want to rely on one UPS system in true emergencies, where one UPS has genuinely failed. They don’t want to voluntarily throw away their safety measures for any period of time if they don’t have to.

@@appleintosh sorry I don’t follow you reply. They are running the load of two ups systems in parrelle they want to do ups maintance. So they shut off both ups systems and switch to a generator . So now they have no ups backup. Generator stops they have lost it . Why not just turn off one ups and let its brother take the full load then isolate the other ups and service it . They would now still have ups backup. Unless they are not running N+ 1. And one ups can’t take the full load ...

@@hotrex7779 Sounds from the video like they are running multiple paralleled generators. If N+1, the loss of a generator shouldn't impact the load. On the other hand, if you take one UPS down for maintenance, you no longer have N+1 UPS, so if a failure occurs to any other UPS while one of them is undergoing maintenance, you drop the load. It may seem like an unlikely scenario but I've seen it happen, where one UPS was being worked on and the other UPS suddenly gave up the ghost, dropping the load.

@@hotrex7779 If they have multiple generators, the risk of one generator dying during the middle of UPS maintenance is mitigated. If they have enough generators to handle the load with one or more generators failed, they don’t have a single point of failure. If they take one UPS offline for maintenance and rely on the other UPS for their backup, that’s now a single point of failure. If mains power is cut off during maintenance, and something were to go wrong where the one operational UPS can’t take the load until the generators kick on, their facility loses power.

@@TehMG I would have guessed the most systems would also be fed using redundant power supplies with separate power rails. In this case you could patch one rail to the gensets and leave the other rail on the spare UPS for added redundancy. Better safe than sorry - I've seen too many controls not entirely delivering the advertised failover capabilities when needed in real life.

Pretty sure they did the transfer properly. It was the UPS maintainence itself that was the problem.

Remember the 2017 outage?

@@k4be. both incidents

That was actually different. The whole Battery system or so made smoke and shit and caucht fire

It could be handled by some capacitor to correct the power factor I think.

Even if you switch to utility, there's still no UPS between the load and the generator. I'm curious how you think they work on the UPS? The genset is sized to handle the load and power factor.

@@stargazer7644 Hmm I don't understand your thought process and you answered a question with a question. It seems you may have some relevant information but unsure how to write it. "Even if you switch to utility, there's still no UPS between the load and the generator." - What does this mean? The question was about a generator powering IT with with no UPS. " The genset is sized to handle the load and power factor." - I'm not sure what size has to do with a difference in power factor and theoretically dropping IT load. Can you elaborate?

"I'm curious how you think they work on the UPS? " - UPS maintenance is performed by placing the UPS into maintenance bypass which allows utility power to bypass the UPS and still power the IT load. You do not need to switch to generator power to perform UPS maintenance. Do you think this? Sorry. I can't tell.

@@steakikan This seems correct. I just can't verify it haha.

With that much power you just assume everything is an ark flash hazard lol. We have big batteries at work, if you were to drop something across the terminals not only would it turn into a gas, your family won't even need to pay for your cremation.

@@redsquirrelftw Right, but the rule (at my plant anyways) is to do an arc-flash study for every high voltage cabinet and place a sticker on each cabinet to designate the EXACT PPE needed for that specific cabinet. We don't walk up to small 480V cabinet wearing a full suit and gloves, you couldn't get any work done safely if you had to do work in the panel. We wear the correct PPE for the corresponding cabinets. That is the importance of arc-flash labels, to know exactly what is needed and not have to guess.

Ya. It's a 6 year old video

you'd be surprised how old the equipment is in a lot of datacenters. the computer equipment may be modern, but the power equipment keeping it going can be decades old. it's very expensive equipment, expected to last a very long time.

Not at all. We just refreshed a Symmetra PX that's nearly 20 years old. (same frame, new electronics.) Those in-row AC units are still being made today (2021).

By going to Static Bypass, you have removed your UPS batteries from the system. This means that if you were to incur an utility outage or a significant sag/swell, your IT loads may be severely impacted. By putting your system onto generator, you have eliminated this particular risk.