What is Thermal Runaway?
  Thermal runaway is a condition caused by a battery float current that produces more internal heat than the
  battery can dissipate. As a result of temperature rise the float current is increased even further, therefore
  generating more heat. This condition may ultimately cause battery overheating, melt down or even fire.
  Refer to section 608.3 of The International Fire Code for regulation regarding this condition.

  How the FS3 - Factstar, detects Thermal Runaway
  The Factstar measures and monitors the battery float current of the string and detects the float current rise
  ratio over time. This indicates thermal runaway before the temperature of the battery increases. Since the
  Factstar monitors other parameters in the battery room (such as room temperature, battery voltage, ripple
  current, etc) it would not trigger a false alarm.

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