What Is Meant By "Inline UPS"?

[olds]

I am looking to put UPS on a 20 amp circuit. I want the outlets on that circuit to have the UPS protection. I don't want to use a UPS that I would plug into the outlet and then the device into that UPS.
Line in - UPS - Breaker - Load
Is that inline?

 

[who?]

I think that inline means that the battery is always powering the output and the charger is always powering the battery so that there isn't any switching.

 

[Carson Dyle]

I think in a home the term would be whole-house UPS. I'm not familiar with them, but I would then suppose that a whole-house UPS could either be online or line-interactive. And, of course, if using it to power an entire house, you'd typically also want a generator, as a UPS powering everything in a home is likely only going to be good for some number of minutes.

 

[JoeBleed]

Online UPS is one that is always running off of the battery supplied power while the charging circuit feeds the batteries.

Inline, i'm not really sure. i'm only used to UPS devices you plug into a wall and then plug the device into. I know they make bigger UPS devices for server rooms and such that are like what olds is asking about. But you might actually be better off looking into an inverter for battery backup/solar systems that will use either solar or grid power to charge the battery bank but have the inverter wired to feed circuits. This would meet what olds is asking about. I don't think you'd need to use solar panels, but you could if you ever wanted too. The inverter will/should feed the circuits with grid power or battery (if the inverter you chose allows you to change it) pending power charges. if the grid loses power it would switch the circuits it feeds over to battery. the units i've looked at (i don't own any) claim it to switch in 16ms or less.

there may be other options, this is just the only thing i can think about. Magnum inverter/chargers are the one's i've looked at the most. there are a few other decent ones.

 

[Mayne]

i'm only familiar with ballasts..hence my grow-up.

 

[ultimatebob]

Damn... how much would a whole house UPS cost? Sounds awesome if you live out in the boonies, but it can't be cheap.

 

[deadlyapp]

Damn... how much would a whole house UPS cost? Sounds awesome if you live out in the boonies, but it can't be cheap.

The tesla wall units are basically whole house UPSs and cost only around 8k IIRC.

Basically any time you have a battery and some other electronics in-line with your system, you've got a UPS. Then you can either power all the time off the UPS, or switch to the UPS when it senses power loss (similar to generator switchover).

 

[Carson Dyle]

I've always wondered what, if any, are the downsides to using online UPS vs. line-interactive. Wear and tear on the batteries? Some power loss penalty? In large data centers with both UPS and generator backup, are those UPS systems online or switched?

 

[olds]

This isn't in my house. It's for a video wall. There will actually be two 20 amp circuits in a double gang box. Each feeding a surge protector. Equipment plugged into the surge protector.
When the power goes out, I only need UPS for up to a minuter or so while the generator kicks in.

 

[Viper GTS]

I've always wondered what, if any, are the downsides to using online UPS vs. line-interactive. Wear and tear on the batteries? Some power loss penalty? In large data centers with both UPS and generator backup, are those UPS systems online or switched?

They're less efficient (due to everything being double converted) and if you're using them at home they put off more heat (due to the lower efficiency) and tend to have always on active cooling vs line interactive that only produce excess heat and noise when they're outputting power.

Data center UPS are near (if not) universally online double conversion.

Viper GTS

 

[Mark R]

I've always wondered what, if any, are the downsides to using online UPS vs. line-interactive. Wear and tear on the batteries? Some power loss penalty? In large data centers with both UPS and generator backup, are those UPS systems online or switched?

Typically large UPSs for industrial or data center are online, although some can be configured into a standby mode, if desired. However, there is a difference between the switching used in an industrial grade UPS and a home/SOHO grade UPS.

Low cost UPSs use a mechanical relay to switch from mains to inverter, and these take time to switch - usually around 10 ms - additionally, the inverter output is usually not synchronised with the mains (so that inverter voltage waveform may be at a random point compared to the mains waveform when the transfer takes place), so there is a power glitch of variable severity whenever a low-cost standby UPS switches.

Industrial grade UPSs use transistor switching - even when in standby mode, the power goes through an electronic transfer switch. Additionally, the inverter output is kept synchronised with the mains voltage. If mains power gets interrupted, the UPS will electronically switch over to inverter output within about 0.5 ms. As the inverter voltage waveform precisely tracks the mains waveform until transfer, the voltage waveform caries on from exactly where it left off.

The main disadvantage of online mode is lower efficiency. Typically industrial units are about 98% efficient in standby mode, and 96% efficient in online mode - but some of the very latest ones get 99%/98%.

Industrial units are generally not "line interactive" - this is basically a crutch for low-quality switched UPSs to reduce the amount of switching that is required. If the mains voltage fluctuates, then the unit can attempt to reduce/raise the voltage, rather than switching.

If you need that in an industrial UPS, you just switch it to online mode, and the output voltage will be regulated independently of the input voltage. In many cases, as long as the input voltage is only mildly anomalous, the internal DC voltage will be regulated and the batteries will not discharge.

 

[Red Squirrel]

Guessing you meant online. Online or dual conversion would mean that the inverter is always running and the load is running off the inverter. The benefit of that is there is no delay between switching to battery when power goes out. With typical consumer ones they are standby, and a relay actually has to switch the output to the inverter as the AC-DC converter is strictly only for charging the battery and not powering the load. They can save money that way by not needing a beefy one.

Basically with an online UPS you have:

120vac hydro in => AC-DC converter generating DC (ex: 54v) -> battery => Inverter => 120vac UPS protected power out.

When power goes out, the AC-DC converter stops working, but the battery is in parallel with the output and connected to inverter so it then takes over immediately as it's part of the circuit. The AC-DC converter's voltage is set to float voltage which is a voltage you can set a battery at indefinitely without overcharging it.

The telcos do this, except they skip the inverter part, (well they still have inverters for some loads) as most of the equipment runs straight off 48vdc. Well it's actually a positive ground system, so it's -48vdc, but same idea. Float voltage for a 48vdc system is actually 54v. If you stick a multimeter on your phone line you'll get about that, and that's actually from the telco's batteries.

For a house, you'd do a 48vdc system with a couple large inverters that can work in parallel so that if one fails you still have power.

 

[Elixer]

I am looking to put UPS on a 20 amp circuit. I want the outlets on that circuit to have the UPS protection. I don't want to use a UPS that I would plug into the outlet and then the device into that UPS.
Line in - UPS - Breaker - Load
Is that inline?

Nope, what you are looking for is a called a "hardwired UPS".
A hardwired UPS is expensive though.

 

[who?]

Gas, coal or nuclear probably works just as well as hydro.

 

[IronWing]

Inline UPS:

-------------------------------------------
|                                         |
|                 UPS                     |
|                                         |
-------------------------------------------

Outline UPS

--------------------------------------------
|                                          |
|                                          |               UPS
|                                          |
-------------------------------------------

 

[snoopy7548]

Guessing you meant online. Online or dual conversion would mean that the inverter is always running and the load is running off the inverter. The benefit of that is there is no delay between switching to battery when power goes out. With typical consumer ones they are standby, and a relay actually has to switch the output to the inverter as the AC-DC converter is strictly only for charging the battery and not powering the load. They can save money that way by not needing a beefy one.

Basically with an online UPS you have:

120vac hydro in => AC-DC converter generating DC (ex: 54v) -> battery => Inverter => 120vac UPS protected power out.

When power goes out, the AC-DC converter stops working, but the battery is in parallel with the output and connected to inverter so it then takes over immediately as it's part of the circuit. The AC-DC converter's voltage is set to float voltage which is a voltage you can set a battery at indefinitely without overcharging it.

The telcos do this, except they skip the inverter part, (well they still have inverters for some loads) as most of the equipment runs straight off 48vdc. Well it's actually a positive ground system, so it's -48vdc, but same idea. Float voltage for a 48vdc system is actually 54v. If you stick a multimeter on your phone line you'll get about that, and that's actually from the telco's batteries.

For a house, you'd do a 48vdc system with a couple large inverters that can work in parallel so that if one fails you still have power.

Good explanation. The industry buzz-phrase for the topology is "true on-line double conversion."

The company I work for has some UPS products (I'm heavily involved in them). Being able to play around with lithium-ion battery packs was a lot of fun.

 

[Red Squirrel]

Good explanation. The industry buzz-phrase for the topology is "true on-line double conversion."

The company I work for has some UPS products (I'm heavily involved in them). Being able to play around with lithium-ion battery packs was a lot of fun.

I imagine lot of UPS systems will start moving to lithium ion, but how does that work, for balance charging and using at same time? Ex: how do you both draw from, and balance charge a pack? Or do they alternate between charge/discharge using more than one pack?

With lead acid you just set it to float and call it a day, but you can't do that with lithium ion unless you want to celebrate the birth of your country and invite the fire department over for the party.

 

[Ken g6]

 

[Carson Dyle]

Is that in front of Kaido's place? Did he order some more gadgets from Amazon for the house?

 

[sdifox]

Is that in front of Kaido's place? Did he order some more gadgets from Amazon for the house?

Instant Pots

 

[snoopy7548]

I imagine lot of UPS systems will start moving to lithium ion, but how does that work, for balance charging and using at same time? Ex: how do you both draw from, and balance charge a pack? Or do they alternate between charge/discharge using more than one pack?

With lead acid you just set it to float and call it a day, but you can't do that with lithium ion unless you want to celebrate the birth of your country and invite the fire department over for the party.

I can't go into too much detail (proprietary design information and all), but the battery pack is never charged while it is in use (i.e. loss of AC or DC input power) - it is simply discharging. There is a regulated charger module that controls the charging current for the battery pack. When a valid source is present and the battery is fully charged, it is kept in a float state. When the battery is charging, the charger is drawing power from the DC bus. The system has an electronic switch module which isolates the battery from the DC bus; it connects the battery directly to the bus when the input source is down, and disconnects it when the input souce is present. Note that this is a military-grade system.

Inside the battery pack are eight 4.2V lithium ion cells arranged in series for each "tray". There are three trays in our 1U pack connected in parallel (200Whr), and seven trays in our 2U pack (500Whr). Each tray contains charge/discharge control and protection, and monitoring circuitry with additional protection (i.e. over-temperature). It's incredibly robust.

 

[Red Squirrel]

I can't go into too much detail (proprietary design information and all), but the battery pack is never charged while it is in use (i.e. loss of AC or DC input power) - it is simply discharging. There is a regulated charger module that controls the charging current for the battery pack. When a valid source is present and the battery is fully charged, it is kept in a float state. When the battery is charging, the charger is drawing power from the DC bus. The system has an electronic switch module which isolates the battery from the DC bus; it connects the battery directly to the bus when the input source is down, and disconnects it when the input souce is present. Note that this is a military-grade system.

Inside the battery pack are eight 4.2V lithium ion cells arranged in series for each "tray". There are three trays in our 1U pack connected in parallel (200Whr), and seven trays in our 2U pack (500Whr). Each tray contains charge/discharge control and protection, and monitoring circuitry with additional protection (i.e. over-temperature). It's incredibly robust.

Oh interesting so it essentially works more like a standby system then.