Simply monitoring the overall plant voltage from your sites
isn't enough to ensure a timely response to developing battery
problems. By the time site voltage levels start to drop, its
too late. In many cases, you have less than 8 hours to repair
battery cells and/or strings before complete failure of the
battery occurs, which likely means service interruption.
Individual cells within a battery string can start to break
down long before the problem is apparent in terms of plant
voltage. If left unchecked, this can eventually lead to 'runaway'
conditions causing heating, as well as generation of hydrogen
gases that can explode. Thermal runaway can also create H2S
gassing which is very corrosive and will damage equipment
within the cabinet. The breakdown of a cell is initially indicated
by a fluctuation in voltage, but this small fluctuation is
indistinguishable when only the overall plant voltage is being
measured. Westronic has addressed this problem by providing
mid-point battery measurement, which can detect an imbalance
between the two string segments, and report user defined threshold
levels as alarms to the Network Operations Center. This proactive
approach can help operations and maintenance personnel address
the problems before they become catastrophic. This protects
the capital investment and can help to reduce service outages
caused by battery problems.