The Eagle Eye BTM-Series Battery Temperature / Thermal Runaway Monitor is a dependable low-cost solution to protecting stationary batteries against over-temperature and thermal runaway conditions. Individual sensors are quickly and securely attached to each battery jar and connected in series from the main unit. Each thermal sensor is sealed to an IP68 rated-enclosure (water, gas and dust proof) and the provided special gel-filled connectors are also sealed against acid ingress, dust, and gasses.

The alarm relays are 'fail-safe', meaning the user will always get an indication of supply failure. Several batteries in the vicinity of each other may be connected in series to the same monitor. In the event of one or more jars exceeding critical temperature, or a break in sensor circuit, the monitor warning relay activates and the warming LED on the monitor is illuminated. Also, at the same time, an LED flashes on the sensor attached to the over-temperature battery jar, indicating the source of the fault. Should more than 6 jars exceed critical temperature, the system critical alarm relay activates - warning of a serious situation in the battery as a whole. The microprocessor utilized by the BTM-Series updates change in conditions every four seconds.
  Longer interconnections, such as shelf-to-shelf and rack-to-rack are simple to accommodate with standard 20SWG cable, and the IDC connectors provided; cable lengths are not sensitive. Sensor installation for a 40-jar battery will typically take less than an hour.

LED Indicators For:

• 1+ Jars Critical Temperature
• 5+ Jars Critical Temperature
• Power Failure
• Sensor Circuit Break

Over-temperature in a standby battery is a potentially serious condition, which is often caused by either a fault condition within the battery cells leading to higher cell temperature, or a higher than recommended ambient temperature promoting a fault within the cell which leads to a higher current draw, and so on. It is a ‘positive feedback’ progression of exponentially increasing temperature often leading to explosion. The International Fire Code (US IFC 608.3) requires that if a sealed battery (or batteries) operated in a single premises contains over 50 gallons of acid the proprietor must install measures for thermal runaway prevention. The National Fire Protection Association also requires protective measures against thermal runaway in NFPA 1. Article 52.

While IFC 608.3 is intended to prevent a catastrophic explosion damaging the surrounding environment, batteries with smaller total amounts of acid should also be protected as they are just as vulnerable to thermal runaway as larger installations. Additionally, operating a standby battery in higher temperatures than specified can seriously shorten its life. Every 10°C above 25°C (77°F) reduces the service life of the battery by 50%.

The only way to prevent the damaging and costly effects of thermal runaway is to have a real-time battery monitoring system in place. The BTM-Series Battery Thermal Runaway Monitor is a cost-effective system that is easy-to-install, scalable, and protects against permanent battery damage in UPS cabinets, substation battery rooms, outside plant cabinets and other stationary battery applications.