maintain the base station of a small Internet Co-Operative. I
bring in high speed Internet by radio from a town 12 miles away and
redistribute on 2.4 GHz to some of my neighbours. The network also has
a weather station and a PC acting as a server to provide network
news and local weather.
the top of the 68 foot tower (left) is the high speed link to Richer
and below it is the 2.4 GHz antennas for re-distribution.
shorter tower, the weather station wind speed and direction sensor is
just below the rotator for the 2M beam antenna and the temperature,
rainfall, and humidity sensor is located in the black box on the short
tower just below the ridge of the house.
the cables from both towers enter through a cable bulkhead through a
lightning protector of some sort. The high speed link is a Cat-5 signal
protected by an ITW Linx Cat-5 Power-Over-Ethernet protector (small
gray box mounted directly on the metal bulkhead). The 2.4 GHz
cable for the Access Point is protected by a 1/4-wave shunt (to the
left of the Linx protector). The assorted rotator, switch, and
weather station signals are protected by 300V 3-element gas tube
protectors (in the small aluminum box just below the bulkhead. RF
coaxial cables have the sheaths grounded at the bulkhead and are
protected by 300V (for VHF) or 500V (HF) gas tubes. Both towers, the
entrance bulkhead, and the house electrical service ground are bonded
by a buried 2/0 conductor. The taller tower was built on a 32"
corrugated surface well that extends 15 feet into the water table and
provides an excellent ground.
Inside the house is the Linksys
router (right) and the Access Point radio, both powered from a UPS with
surge suppression, and on the other side of the room is the display for
the Davis Vantage Pro 2 weather station. The Co-Op server is located in
the basement and connects to the router with a Cat-5 cable and to the
weather display with a serial cable.
around my property, I have a low-voltage control system that allows
remote control of a number of lighting circuits (1 in the house, 2 in
the garage), activation of the garage door, and conveys the door bell
signal to both the house and workshop from any of three pushbutton
stations in various places.
to right: one of the button stations, one of the relay panels, the
surge suppression on the 12 pair cable between the house and the
Having been in "the lightning business" for many years, I thought everything was well protected!
the night of August 12/13 a severe
electrical storm moved through southern Manitoba. Hot muggy weather
gave rise to a lot of cloud to cloud lightning and around 11:30
p.m. the power went off. With no fan, I moved down to the main floor
where it was cooler and since
the power outage was wide-spread, I shut off the UPS that protects and
backs up the Internet Co-Op and settled in to a chair near the weather
station display. At 12:28 (approx.) lightning struck somewhere on the
property and I saw an electrical flash between the cable on the weather
station display unit. I mistakenly assumed lightning stuck the 68 foot
following morning, with power restored, I powered-up the Internet Co-Op
and found everything was in working order. The weather station was dead
however. Subsequent investigations showed the weather station display,
its power supply, and the serial interface module had all been damaged
and were replaced. I also later found one of the protectors on the 12 pair low-voltage control cable had failed short.
could not understand how the
lightning energy reached the weather station display despite the
extensive protection until I noticed the top of the power pole in the
yard. Lightning struck the west face of the wet pole (note the
blackened pebbled texture), wrapped around the pole and picked up the
drop-wire insulator frame (very bottom of the picture) thus causing a
surge on both phases (to the house and garage) as well as the
To combat repeat performances, I installed a "whole house surge suppressor" that protects against power line surges.