User`s guide

Chapter 2 __________________________________________________________ Product Overview
VAISALA_______________________________________________________________________ 29
Transient Protection Devices
Each sensor input in the logger has a varistor (VDR) protection against
induced transients. The maintenance terminal I/O port has transzorb
diodes in their inputs.
In case of long signal cables, additional transient protectors can be
installed on the DIN-rail. These surge arrestors consist of a combination
of VDR, transzorb diodes, and coils, thus providing excellent
protection.These are easy to change in the field without tools.
0407-016
Figure 14 Surge Arrestor for Serial Lines
Optional coaxial surge arrestors will be used for UHF and VHF
antennas as well as for the RF signal input when a radio or satellite
equipment is used.
0407-017
Figure 15 Surge Arrestors for AC (Mains) Power