Station protector use.
Telephone lines are subject to electrical hazards from three sources: electric light, power
lines and lightning. The primary means of protecting telephones circuits from electric light and power
lines is to plan construction which will prevent contact between the two kinds of lines. The best
methods of construction, however, cannot be relied upon to prevent accidental contacts. Station
protectors are the only practical means of protecting the station apparatus against lightning and possible
contact with electric light and power lines, and are required wherever such accidental interference is
possible. There are basically two types of protectors, fused, Figure 29 and fuseless, Figure 31.
Reliable 2000 protector installed
Wiring reliable 2000 substation
outside (cover not shown).
Figure 31. 123 Fuseless protector.