A set of TTS-VF-12/4S DC communication signal surge protector is installed in elevator, escalator, power distribution equipment, self-supplied generator, power equipment control line for lightning protection.

A set of TTS-VF-12/4S DC communication signal surge protector is installed in HVAC system cold and heat source units, air conditioning units, fresh air fan unit control lines, water supply and drainage system pumps, water tank water level control lines, DC power supplies, lighting control lines and so on for lightning protection.