Anyone experienced in IT UPS systems?

[Frank]

We have jacks of all trades here so, I figured I'd throw this out there. I was curious about UPS systems with battery backups. Smaller ones, maybe rack mountable. I personally have never used one, but I assume that like most things with batteries, if you never allow it to discharge and charge ever so often and only have it in standby, then the batteries probably fail prematurely and when there is a power loss, the battery backup is useless. Am I right?

Do they typically have some kind of means to check battery condition without actually going through such a cycle? Either by remote monitoring or an indicator light on the device?

My client has hundreds of sites using probably the cheapest of UPS systems and on occasion, they fail without warning. We find out because the switch/router/etc connected to it shows down, but there is not way to tell if it is a site power failure without a tech being dispatched. More times than not it is a power issue rather than the device. Sometimes they find that the site had a UPS, but just couldn't power the device long enough for any graceful shutdown could be performed.

I was wondering if there are procedures, preventive maintenance for cycling UPS that do not incur an interruption of the client's services. How long would such a procedure take?

[Ratt]

For rack-mountable UPS systems, generally there is an I/O card you can buy to put in a server that will connect via cable to the UPS that will monitor statuses. APC is the brand of UPS and monitor card our company uses.

[UserX]

Most UPS chassis are good for 8 years, batteries for 4. Any good UPS you can add a web card so you can monitor UPS health remotely. Battery health, current load, estimated run time, etc. You can also setup alerts to auto generate a ticket in your ticketing system.

If you have an extended power outage, removing the batteries from the UPS after everything has been gracefully shutdown will greatly extend their life. Discharging them 100% takes a toll.

I can't say enough good things about APC. Their support is great, and their units are simple to service. We also use some Eaton's, and they're a PITA. If something fails, they want to replace the entire control module, which is almost $10k. Doing that to replace something simple like a fan failure is ridiculous.

[lowthreeohz]

We use APC at our sites and report alarms back via the site switch. No experience with smaller rack mount stuff though, all ours are standalone banks

[TeeShock]

We only spec apc for small applications. Have you considered a small flywheel cabinet? No need to worry about batteries!

[Frank]

We only spec apc for small applications. Have you considered a small flywheel cabinet? No need to worry about batteries!

What is a flywheel cabinet?

[TeeShock]

What is a flywheel cabinet?

A flywheel machine is a mechanical battery. Normal/utility power is passed through a double conversion that energizes the flywheel. In the instance of an outage, the energy stored in the flywheel carries the load until (hopefully) your gens fire up. The size of these modules are a lot smaller than a standard battery cabinet. The maintenance is minimal, something like a bearing swap every ten years vs. replacing batteries. The smallest one I've seen so far is 150kva. It's really an interesting technology that is easily confused with drups. Most clients want to stick with what they are familiar with.

[S_K]

Flywheels are old technology. The reason no one uses them any more is that run time is usually not long enough to fire up a generator if it fails on the first crank.

Flywheels work great for spikes, brownouts, and converting power from 2 phase to 3 phase though.

[S_K]

Another useful product is a smart power strip. APC makes some nice ones. They are IP adressable and will give you voltage and amps in real time. Some will also allow you to power cycle a device as well.

[jw33]

We have jacks of all trades here so, I figured I'd throw this out there. I was curious about UPS systems with battery backups. Smaller ones, maybe rack mountable. I personally have never used one, but I assume that like most things with batteries, if you never allow it to discharge and charge ever so often and only have it in standby, then the batteries probably fail prematurely and when there is a power loss, the battery backup is useless. Am I right?

Do they typically have some kind of means to check battery condition without actually going through such a cycle? Either by remote monitoring or an indicator light on the device?

My client has hundreds of sites using probably the cheapest of UPS systems and on occasion, they fail without warning. We find out because the switch/router/etc connected to it shows down, but there is not way to tell if it is a site power failure without a tech being dispatched. More times than not it is a power issue rather than the device. Sometimes they find that the site had a UPS, but just couldn't power the device long enough for any graceful shutdown could be performed.

I was wondering if there are procedures, preventive maintenance for cycling UPS that do not incur an interruption of the client's services. How long would such a procedure take?

A UPS battery is usually good for about five years as long as it is kept at about 77 degrees. For a small valve regulated lead acid (VRLA) battery any usage will slightly shorten that time. Some UPS will perform a routine test that puts a slight amount of load on the battery for a specific time and monitors the battery voltage. If the battery voltage falls below a threshold the UPS will alarm or can send out an alert if it is being remotely monitored. A UPS relies on the battery during a utility power outage and will not support the load if the utility source is not present. In other words without a good battery it does not work when it is needed the most. If these are small single phase <1kw UPS it might be cheaper to just replace the entire UPS compared to replacing only the battery. For something that small I wouldn't even bother to test them that often because it cost a decent amount of money. Instead I would just record the battery date codes and schedule a battery replacement every four years. FWIW I work in field service for a OEM UPS manufacture for a little over 13-years.

[jw33]

There are a couple of sites we work on that have some of the newer flywheels and the ones we sell with our box don't run on a mechanical bearing. The wheel is levitated with a magnetic field inside of a vacuum chamber and spins at 33K RPMS. At full load they are sized to get about 15 seconds of run-time. These are 1MW UPS and the diesel generators/ATS are setup to be running and transferred within about eight seconds of an outage. I was skeptical, but it was fully tested at start-up and has been working mostly trouble free for several years now.

[mikeb]

There are a couple of sites we work on that have some of the newer flywheels and the ones we sell with our box don't run on a mechanical bearing. The wheel is levitated with a magnetic field inside of a vacuum chamber and spins at 33K RPMS. At full load they are sized to get about 15 seconds of run-time. These are 1MW UPS and the diesel generators/ATS are setup to be running and transferred within about eight seconds of an outage. I was skeptical, but it was fully tested at start-up and has been working mostly trouble free for several years now.

The flywheel is good as long as the generator starts in time.

I worked at a company one time that had a power outage and the generator didn't start. Turns out some genius in accounting cancelled the maintenance contract on the generator to save money and it had moss growing in the fuel tank.

Another time the generator started but the most important cabinet in the computer that the company used for it's business wasn't wired to the emergency power. Everything else (including the line printer) was wired and stayed on