Reducing the charge of Uninterrupted Power
Efficient Power Supply Management Saves Resources

By Preston L. Mintz, President, Dynacell Corp.

    Equipment power loss is like death to broadcasters. To assure uninterrupted service, at least until normal power is restored, use of uninterrupted power supplies (UPS) has become universal. Most people consider UPSs (basically storage batteries) necessary evils; not only are they nuisance to install and maintain their yearly costs can sometimes run into the high six figures. What’s worse, most broadcasters are paying too much for their UPSs – in some cases 30 to 50 percent more then they should.
     There are many ways to help reduce direct UPS costs, cut associated maintenance/labor costs, and realize savings of one-third to one-half of your current UPS budget. All of these can be achieved by proper system/battery selection, management, and maintenance. Many broadcasters (TV stations/cable headends) maintain traditional “sales only” supplier/customer relationships with their battery providers, which has generally resulted in their purchasing more batteries then they need. These batteries prematurely age from disuse and must be discarded. There are instances where some stations have purchased 500 batteries at once, and have had to discard 200 of them after only five months.
     A UPS system is typically composed of three, four, or eight batteries. The size of the system is dependent upon many factors. For example, most broadcast facilities require power between eight and 15 amps to overcome a power interruption. Although these are basic load calculations, power requirements are dependent on system resistance and how the power supply boxes are set up.
     Every system stands on its own as far as its load demands. Most systems are designed to provide backup power between one and three hours, but that also depends on the circumstances that include the physical location of the station. For example, how many power supply units are situated in a square mile or other geographic area? In a metropolitan environment, many times a power interruption can be resolved in an hour or less; in amore rural area, it might take three or four hours (sometimes even longer).
     Some metropolitan areas, for example, have two and three times the number of power supplies as their rural counterparts; this is based upon power needs as opposed to anticipated system downtime. Configuring a proper UPS system is obviously dependent upon a complex combination of issues.
     With regard to the batteries used in UPS systems, it is not good procedure to mix a new battery with older batteries, since the capacity of the newer battery will be drawn down into the older batteries, regardless of how many batteries that system contains. Instead, the older batteries should be removed and matched with the batteries of the same capacities (essentially a function of battery age).

Proper UPS Testing is a Key to Life Extension
    Many broadcast companies are also using out-moded battery testing procedures, mainly because most popular test equipment doesn’t provide accurate indications of battery’s true condition. For example, most cable TV headends use transient voltage meters and load testers that can provide inaccurate readings, depending upon the cycle or flow charge on the power supply. Dynacell uses — and recommends — a conductancy tester (Midtronics Inc., Oak Ridge, IL) that indicates the condition of the plates for a true determination of battery power. Voltage meters and load tests can be misleading. A voltage meter may indicate 12.65 volts, even though the battery may not be able to produce adequate amperage.
     Also, a load tester may indicate that a battery needs to be replaced when it is merely discharged. The Midtronics conductancy tester has been found to be fast, safe, and accurate for proper evaluation of battery condition. Another valuable maintenance tool (also manufactured by Midtronics) is an infrared heat sensor. Usually a hot battery is a bad battery.
     Basically, after three or four years – regardless of the maintenance program in use—maintenance is no more than changing batteries in the power supply boxes. At that point checking them might be wasting time, since all batteries have a finite life expectancy.
     Other maintenance issues could involve upgrading the power supply boxes, perhaps to accommodate higher loads or longer operational periods. Maintenance means different things to different organizations, depending upon how disciplined the system is.

Sensible Ordering Saves Substantial Money
    By ordering UPS batteries on an “as needed basis” (weekly or monthly, for example) the broadcaster always has fresh batteries and minimizes the possibility of both UPS failure as well as discarding good batteries. And by combining proper testing methods with sensible ordering policies, UPS purchases can be reduced by 30 percent or more.
     We know of one cable TV provider that was ordering (and receiving) about 1,000 batteries at a time, and installing about 100 a month. At the end of six months, 500 of these batteries had to be discarded because of improper charging and storage methods. The station’s chief engineer could have saved the cost of those 500 batteries (approximately $50,000, based on a typical UPS cost of $85 to 115) if inventory management and maintenance procedures ad been more efficient.

More Information is More Power
    Proper inventory management will help eliminate this waste. Sometimes as few as 10 batteries are all that is needed. Ideally, a battery supplier should maintain almost daily relationships with customers, so as to be aware of rebuilding schedules that allow it to provide customers with an as-needed inventory. Providing quarterly reports to customers by listing warrant reports on batteries supplied and returned, ordering/installation patterns for management analysis, and other information design to assure continuous power.
     Here is a typical example from a cable TV provider about to do a rebuild with 500 power supply boxes and 1,500 batteries. Instead of ordering 1,500 batteries, since they are likely to be installing about 50 power supply boxes a month, they should order only 150 batteries a month so as to always have fresh batteries. By ordering UPS batteries this way, battery storage requirements are virtually eliminated, since there are no excess inventories to manage.

Charging, Monitoring, and Handling UPSs
    To extend the life of any battery (all things being equal with regard to battery quality), proper charging, monitoring, and testing are the most critical factors. No one enjoys maintaining batteries. In the broadcast and cable provider industries, batteries are considered “dirty and dangerous”; they are heavy, and a technician must be careful installing or handling a 75-pound battery from a bucket. Some batteries have handles that help add convenience and safety during installation or removal.
     Proper charging is also critical to extending battery life. Surprising, many broadcast and cable TV providers are unaware of proper charging methods for their UPS batteries. Battery chargers must limit voltage to no more than 14.1, and no less than 13.8 (at 68 degrees F). Automotive battery chargers are not suitable for UPS batteries.
     We’ve had excellent success with Schauer’s (Cincinnati, OH) automatic battery chargers, designed especially for sealed, valve-regulated batteries. These chargers are temperature-and-voltage-compensated, protected against reverse-polarity and short-circuits, and provide adjustable voltage levels to maintain proper charge conditions for batteries to different ages.

Cost Savings Enhance Profits
     For the past few years, Dynacell has conducted a unique training program to educate technical management and maintenance technicians on all aspects of their UPS program, with results including thousands of dollars of savings. Broadcast cable, and TV stations have eliminated wasteful purchasing cycles and its negative effects. The program consists of two to four training sessions a year, where technical management and maintenance people are shown proper techniques for UPS testing, charging, maintaining, storing and inventory management.
    Seminars cover battery handling and safety issues as well, even to the level of demonstrating the proper lifting techniques to prevent back injuries during installation or removal. Middle and top management people at broadcast and cable TV providers have also become more interested in our UPS training program.
     Basically, these people want to become as valuable as possible to their organizations in today’s unstable and unpredictable business climate. If we can show them how to save 20 to 40 percent of a relatively large budget (in some cases the savings can be in the millions of dollars), top management understands the value of these savings vs. the need for revenue generation to accomplish the same goals. As a result, we’ve found that management at all levels has a keen interest in our UPS seminar program. For more information, please contact Dynacell.