BW SOLAR Waterboy, Installation Manual

Page: 7 / 27

7
Lightning Protection
A surge induced by lightning is one of the most common causes of electronic controller failures in solar
water pumps. Damaging surges can be induced from lightning that strikes a long distance from the
system, or even between clouds. The risk of damage is greatly reduced if these instructions are
followed.
Lightning protection is recommended under any of the following conditions

Isolated location on high ground in a severe lightning area

Dry, rocky, or otherwise poorly conductive soil

Long wire run (more than 30m) from the controller to the bore head, or to the float switch
Lightning rods, surge arrestors and additional lightning protection devices may be obtained from a
local supplier.
Float switch cable.
A long run of control cable to a float switch in the storage tank can pick up damaging surges from
nearby lightning. The best protection is to use shielded cable. Shielded cable has a metallic foil or braid
surrounding the two wires. Earth the cable shield at the controller end only NOT at the float switch.
This will reduce surges induced by nearby lightning. This product is suitable for direct burial, but not
for submersion in the water.
Legal expectation
CHECK with local authorities on any Lightning protection obligations.