for all applications volume control signals can operate separately very well suited for fire alarm systems and direct control due to low power consumption self-synchronising sounder for clear tone perception [...] 2 different externally controllable tones Here you can find suitable Zener barriers. protection system operating between +60 / –40 °C Electrical data IS-mC1 Rated voltage 24 V DC Operating range 16–28 [...] connected via a zener barrier (max. 28 V DC, 93 mA DC, 0.66 W) or galvanic isolator, specified by the system certificate Choose your LED in one of the following colours: yellow/amber, red, green, blue. Further