Whether you buy dedicated UPS batteries, marine batteries, AGM batteries, GEL batteries or common car batteries, poor care reduce their service lifespan by as much as 65%. In other words, you can easily triple your overheads. Perhaps some car drivers can afford to be negligent about battery care, but anyone who depends heavily on the reliability of those batteries—such as offshore shipping or data centres—cannot afford to neglect them. They are simply not an install-and-forget component. The following basic care or UPS battery maintenance guidelines and using a UPS battery testing service will maximize your long-term cost/benefits.
Numerous factors contribute to battery problems, including electrical distortion and extreme weather, but more common causes include over-discharge, recharging delays, over-frequent cycling and the use of inappropriate chargers. An unbalanced array of batteries with varied capabilities, either because they are different products or because they are different in age and condition, will not help, nor will an underpowered battery array for the supported load.
Some basic UPS battery maintenance guidelines for battery care:
— Make sure the system is adequate for the load and remains
— Keep everything grease and corrosion free
— Maintain a cool ambient temperature, with neither hot nor cold extremes
— Do not discharge deep cycle batteries any more than necessary
— Avoid frequent cutting-in that causes rapid or fluctuating charge/discharge cycles
— Always recharge them as soon as possible and never allow the charge to decay in storage
— Use a UPS battery testing service to monitor your equipment over time
It is difficult to monitor a battery, let alone an array, without the help of a UPS battery testing service. This is because you’ll need to take exact measures of each cell’s electrical performance over time to figure out what’s going on within your batteries. It is common for one or more internal cells to degrade or fail before others and when they do, they accelerate the decline of neighbouring cells. The same is true in battery arrays—one failing battery accelerates the deterioration of others. The same interdependent principle applies to supporting capacitor banks. This therefore highlights the need for a UPS battery maintenance guidelines checklist.
You need a professional battery testing specialist to identify how each cell is holding up over time so that you can replace them early and extend the lifespan of the whole system.
The health of a battery cannot be determined by a single metric, such as voltage. Your batteries must be able to instantly produce the appropriate voltage and current when called for, and then keep it steadily under potentially changing loads to function as needed when needed. It should be able to continue discharging as long as required, and then recharge efficiently and maintain its charge availability over time. Various tests are needed to examine all these parameters, and those needed may depend on your particular equipment, but the main ones are the following:
- Impedance tests examine the resistance and voltage of individual battery blocks. This is a good measure of battery health over time. When the internal resistance has risen by about 50% from its initial baseline value, it should be considered to have failed and is due for replacement. However, the chief benefit of regular testing is to predict that date in advance so that you can schedule and budget for the intervention.
- Conductance tests measure the battery’s ability to generate current. Again, the point of these measures is to predict a point of failure and avoid it.
- Load bank tests involve applying realistic loads on the system and measuring the actual rates of discharge and recovery. This usually means the system has to be swapped out of service for testing.
Specialist battery testing engineers will also examine your other attached equipment such as the charger, capacitor banks and cooling fans. Controlling dirt and corrosion is also very important, so the engineer will address any immediate issues you have with grit, grease, cable oxidation or terminal corrosion.
Of course, a professional testing engineer will also warn you if you don’t have the most suitable equipment for the job. There is currently a big drive toward better power storage and permanent battery monitoring solutions, and UPS professionals will keep you abreast of all the exciting new opportunities.