All good networking server setups require a UPS (Uninterruptible Power Supply) to keep the equipment going long enough to properly shutdown after a power outage has occurred.
What is sometimes neglected is to regularly check your battery to ensure that it’s holding a charge, should the time come when you have to use it.
This is done by connecting the UPS to the network or a Server, and then running the proper diagnostic testing on the battery. Often times the software or the controller will test the battery on it’s own interval, but without the software you may not notice the gradual changes that occur when the battery slowly is no longer holding as much as a charge, or is able to keep the system up, as long as it used to.
Once this occurs, it is time to replace your battery.
Here’s a scenario, you have recently been assigned a new client, and they already have a power structure in place. A week or two goes by. One of the UPSs lights are all green, but constantly blinking. What does this mean, and what do you do? Here’s a little guide you can follow:
Battery light is Red
The battery is no long holding a charge
The charge light is green, but blinking.
The battery is only able to keep the power going less than what it is supposed to. Default is usually 2 minutes.
If you see red on the battery, then it’s a no brainer, time to replace the battery.
Back to the scenario, if you see blinking green, it’s a little tricky. This doesn’t mean that the battery is necessarily dead, it just means that the controller is saying that the battery can’t hold power on it’s own for longer than 2 minutes. Here’s what you do:
1. Login to the APC monitoring software and perform a runtime calibration test
2. If after the calibration test the lights are still blinking – it’s time to get a new battery. Sometimes though, it will return back to normal after the run time calibration test (about 1 hr after). In which case, all it needed was a good kick in the pants.
How to get a new battery:
1. Write down the model number of the unit and also get the serial number (The exact model number is at the rear of the unit, or behind the face plate.)
2. Get the serial number of the unit (by the face plate).
3. Get the serial number of the battery (on the battery towards the face plate).
Note: On some APC UPSs you can remove the battery, while the UPS is still plugged in so as not to have to shutdown servers.
4. Call APC to see if the battery is under warranty. If not, it’s still recommended to buy a battery through APC since they give a warranty on them.
Replacing the battery:
Once you get the new battery, check to see if the battery is hot swappable. If it is, go ahead and replace it with the server still connected. After replacing the battery INITIATE A RUN TIME CALIBRATION TEST FROM THE APC MONITORING SOFTWARE. If you don’t, the time wont be calibrated on the APC and you may get false results, or the battery may run down a lot sooner than it should. If you can’t install the APC monitoring software, then you will need to:
1. Charge the battery until it is full on the front panel
2. Power down all of the servers, plug a CRT or another non critical item into the UPS and unplug the UPS from it’s power source. Allow it to run down, and then charge it again. Doing this will initiate a automatic built in run time calibration.
Once you’ve been at a client long enough you will get a feel for how long a battery lasts in a UPS. It’s recommend that you replace it around the time that you’ve noticed it tends to begin to deteriorate. If they were all installed around the same time, try to replace them all at the same time – because if one fails the others are probably soon to follow (especially if they’re the same model).