Friday, April 9, 2010

UPS Battery Replacement

Commentary: My old UPS battery died; rather than buying a new unit, I replaced the battery. A UPS is recommended if you have dirty power -- and my power was dirty because of a piggy laser printer.

An un-interruptable power supply (UPS) provides battery power for your computer when the main grid fails. During a "power anomaly," these relatively inexpensive devices keep the computer running for about 10 to 12 minutes -- giving enough time to save your work and shut down. If you are not at home, included software can gracefully shut down the computer.

The real reason for a UPS is to protect the hard disk from brownouts and power surges. Power gremlins like these can fry a computer's motherboard but a bigger fear is corrupting the hard disk -- which would ruin everything. As always, data is more valuable than hardware.

Related Keyliner Article: UPS turns off and on

My UPS is Pooped-out:

My (six) year old APC cs350 UPS has been slowly dying. The unit has a sealed, lead-acid rechargeable battery and like a car battery, it can lose its punch. When it was new, it ran the computer and two monitors for about 10 to 12 minutes -- but now it can hold a charger for 2 or 3 seconds.
The final straw came last week when my Brother HL-2040 laser printer (Keyliner reviewed here), printed a page and then surprised me by rebooting the workstation. When it crashed, a document was lost, the RAID array failed, and all kinds of other mayhem occurred. As I found out later, it had been crashing each time the children printed from their laptops -- but they never noticed my computer crashed. The prior week I noted the RAID was constantly rebuilding (article: Raid Power Gremlins) and when I put two-and-two together, I understood the issue. Bounces like this are hard on equipment and they were happening far too frequently.

Although it is safe to plug an inkjet printer into a UPS (on the surge-side), one should never plug a power-hungry laser into the UPS. But out of necessity, the printer and computers live on the same household circuit -- this is nearly the same as being plugged in on the same power-strip. When the printer fires up, it pulls an amazing 450 watts and the lights throughout the house (and probably throughout the neighborhood), flicker. The power company rejoices.

Sadly, the UPS was compensating for this and I never knew. Each time the printer printed, the circuit had a mini brown-out and the UPS stepped in to save the day -- that is, until it became too tired to work.

APC cs350:

I am partial to the APC brand cs350 UPS, which costs about $70 and you can get one at any office-supply store. It features a user-replaceable battery and surge protection for your phone/modem.

Installing a new UPS is a cinch: Plug it into the wall. Plug in the computer and monitor, and you are set. I don't bother with the USB connector, which can tell the computer to shut down, but I probably should.

Most UPS's, including this one, have two rows of plug-ins. One side is battery and surge-protected and the other is simply a surge-protected circuit (with no battery). Here is the back-side view of the cs 350:

User Replaceable

At first, I was going to buy a new, smaller UPS, figuring it was cheaper than a new battery. Replacement batteries can be bought directly from APC's online store for $50, which is the same price as a new, smaller UPS.

But after a little searching, a replacement battery was found at a local retailer (BatteriesPlus) for (then) $33.00 -- now $40.00. If you mail-order, the battery is significantly cheaper, even with freight and they include a free return-ship for your old battery (you must recycle lead-acid batteries - they are dangerous).

To replace the battery, literally, turn the UPS on its back, and pull the battery out, unplugging a red and black cable. It takes about a minute.

The battery is surprisingly dense and weighs about 5 pounds but with this new battery, I expect to get another 4 years service. But long before then, when the laser printer runs out of toner, it will have a mysterious hardware failure, probably involving a baseball bat. This will force me to buy a new, less hungry printer.

Your comments are welcome.

Related links and products:
Staples: New cs350
Raid Volume Rebuild
Raid Power Gremlins

Keyliner Article: UPS turns off and on

Replacement Battery: 12V 28W 7.2AH
GP 1272 F2  (APC)
GP1272 F2
Werker 12Volt 7Ah AGM Battery .250 Terminal WKA12-7F2

05201050BAT, 182735, 23275, 6DW9, 6FM6, 6FM6A, 6FM7, 791181624, B00007, BAT0062, BAT0370, BD712, BERBC31, BP127F, BT712, CB1270, CFM12V65, CP1270 , CS36D12V, DG127F, EP1229W, EP1234W, EVA12-7.5F2 , F6C127BAT, GNBSP12V7F1, GP1270, GP1270F2, GP1272, GP1272F2, GT12080HG, HE12V77, HEPNP712, HEPNP712FR, HP712, HR1234WF2, HR1234WFR, HR912, LC-R127CH1, LC-R127R2CH1, LCP127R2P, LCR127R2P, LCR129CH1, LCR12V65BP1, LCR12V65P, LCR12V65P1, LCRB126R5P, MBCFM12V72, NPW3612, NPW4512V, PE12V72F1, POWPS1270F, POWPS1270F2


  1. Good article. I, too, have had a positive experience with BatteriesPlus. Purchased a cell phone battery. Will use them again.

    An interesting aside - there are true UPS's and battery backups. What's the difference? A true UPS runs on the battery continuously and the AC current keeps the battery charged. This also provides line conditioning. The Battery Backup runs on the AC power & when it fails, there is a split second when it switches from the AC to the battery. While technically this is not a UPS, most home users would be well served by such a device & with the cost savings in their pocket.

  2. I was not aware of the difference. Is it safe to assume that APC cs350 is a UPS?

  3. I didn't know for certain. I went to the APC web site & looked up the CS line. It states
    "APC CS - Best value battery backup & protection for business computers."
    As I remember (it has been a while) most of the true UPS devices started in the $200-$300 range and went up quickly from there.
    This is my OPINON but the odds of a PC writing at that exact second the switch over takes place is far less than a server. Also the value of the data on a server is far greater than that on a PC.

  4. The issue may be moot for a single computer. Whether the power always runs through the battery or if it switches over in a milli-second is probably inconsequential -- as long as the results are the same.

    Thanks for your comments.


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