Power Substations

Costs for ensuring reserve battery power for generation station controls, transmission switchgear & substation reclosers was becoming excessive. Physical inspections by technicians was expensive and inefficient.

Approximately 4% of the time the inspectors would find entire battery strings dead as a result of one battery going bad and causing all other batteries in the string to fail.

With weighted labor added, string replacement cost in excess of $15,000 for a 24 battery switch. Additionally, batteries could fail in as little as two weeks so the inspections weren’t frequent enough. Lastly, battery service life was restricted to five years to keep the string failure rate from going higher.


The solution to the problem was installing individual battery monitors remotely monitored providing realtime data on temperature, impedance, and voltage.

EMSYS Design Inc’s Cell SPY System was selected for its ease of installation, wireless communications, and total cost of ownership (TCO) model.


Alerts were automatically generated by the battery monitoring application the instant a monitored battery’s performance began to deteriorate. Immediate replacement of the offending battery totally eliminated string failures. Annual inspections of the batteries were no longer required because the monitors provided the coverage. With the historical performance data accumulated on every battery, usable service life was increased 40% to 7 years.


Eliminating string failures, terminating annual site battery inspections, and extending battery service life resulted in a cost savings of almost 48% of the annual cell tower battery expenses with the added benefit in ensuring 100% confidence in the ability to provide service if power was lost at the tower site.


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