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Operation Manual V.34 - Modems, Version 07/97
Chapter 7
7.4
Lightning and Overvoltage Protection
Modem failures can be caused by discharges or overvoltages from the
telephone access side or the operating voltage whenever lightning
discharges occur. Electronical installations within a distance of 1.5 km
are subject to hazards when thunderstorms occur due to electro-
magnetical fields and line overvoltages.
The modems feature a special protection against overvoltages from the
telephone access side (ref. to block diagram below).
FKS 8
E
La
Lb
a2
b2
G
3
5
2
8
1
4
115 V
115 V
115 V
115 V
For leased line applications and especially for operation in areas with
frequent thunderstorms further protection should be installed. Lightning
protection is available (in Germany) from the manufacturers listed below:
Phönix Contact GmbH & Co.
P.O.Box 1341
32819 Blomberg
or
DEHN + Söhne GmbH
92306 Neumarkt/OPF
Tel. (09181) 901 - 0
Applications
Summary of Contents for LOGEM 928
Page 8: ...8 Operation Manual V 34 Modems Version 07 97 Contents...
Page 10: ...10 Operation Manual V 34 Modems Version 07 97 General...
Page 12: ...12 Operation Manual V 34 Modems Version 07 97 General...
Page 32: ...32 Operation Manual V 34 Modems Version 07 97 ON Chapter 2 Switches Description...
Page 42: ...42 Operation Manual V 34 Modems Version 07 97 ON Chapter 2 Switches Description...
Page 66: ...66 Operation Manual V 34 Modems Version 07 97 AT Chapter 3 AT Commands...
Page 102: ...102 Operation Manual V 34 Modems Version 07 97 AT Chapter 3 AT Commands...
Page 104: ...104 Operation Manual V 34 Modems Version 07 97 REG Chapter 4 Register Description...
Page 124: ...124 Operation Manual V 34 Modems Version 07 97 V 25 bis Chapter 5 V 25bis Commands...
Page 134: ...134 Operation Manual V 34 Modems Version 07 97 Chapter 6 Dial Backup Features...
Page 142: ...142 Operation Manual V 34 Modems Version 07 97 Chapter 6 Dial Backup Features...
Page 144: ...144 Operation Manual V 34 Modems Version 07 97 Chapter 7 Applications...
Page 168: ...168 Operation Manual V 34 Modems Version 07 97 Chapter 7 Applications...
Page 170: ...170 Operation Manual V 34 Modems Version 07 97 Chapter 8 Appendix...
Page 192: ...192 Operation Manual V 34 Modems Version 07 97 Chapter 8 Appendix...
Page 199: ...199 Operation Manual V 34 Modems Version 07 97 Chapter 8 Appendix...
Page 200: ...200 Operation Manual V 34 Modems Version 07 97 Chapter 8 Appendix...