Lightning Transient Coupling to Signal Lines - RME111 - RWS200 - AWS310-SITE - AWS430 - RWCC - AWS310 - FOC201

Grounding and Lightning Protection in Vaisala Outdoor Installations Technical Reference

Document code
M211786EN
Revision
B
Language
English (United States)
Product
RME111
RWS200
AWS310-SITE
AWS430
RWCC
AWS310
FOC201
Document type
User guide

Lightning transients have three main coupling paths:

  1. Radio-frequency interference (RFI) with limited impact on anything. It can cause data packet loss or similar.
  2. Induced voltages through magnetic or capacitive coupling. Use shielded signal cables and twisted pairs that are fairly immune against differential coupling. Still, common mode voltages can cause component damage.
  3. Surge currents caused by localized shifts in ground potential. They cause relatively low-voltage, long-lasting common mode pulses, which can burn series impedance components in multi-phase surge protection circuits.

Ground potential shifts are a common cause of modem failures in systems connected to both the AC (mains) power and telecommunication networks.