As an alternative to electronic sensors, the Matsuo MQT thermostat offers UPS system installers a simpler and more cost-effective solution. Matsuos MQT thermostat has a twin-bimetal system that creates a control which is capable of switching over one million cycles. Accuracies of 1.5K and differentials down to 3K1K are readily available, with repeatability as small as 0.2K.
The thermostats IP64 plastic housing can be readily fixed to the side of a battery and so each one can be safely monitored.