In the Shop
As a farm machinery mechanic and writer, Dan brings a hands-on approach that only a pro can muster. Along with his In the Shop blog, Dan writes a column by the same name as well as the Shop Series for Farm Journal magazine. Always providing practical information, he is a master at tackling technical topics and making them easy for all of our readers to understand. He and his wife, Becky, live near Bouton, Iowa.
Hanging Electrical Harnesses
Jan 13, 2013
Modern electrical connectors used in farm equipment electrical harnesses have come a long way from the days of male/female spade-type connectors. Modern Weatherpak- and Deutsch-style connectors use rubber grommets and seals to virtually waterproof the connection once the male and female connectors are twisted or "clicked" into place.
BUT--moisture can sometimes still weasel its way inside those connectors if they are hung, draped or mounted vertically. A little moisture and corrosion wasn't a big deal back in the days when connectors were transmitting 12 volts, but today's can-bus systems work on very low voltages that are notoriously sensitive to even minor corrosion. Wiring harness connectors on planters are especially susceptible because they commonly hang from the back of the tractor cab. Water runs down the wiring harness and pools in the upper end of the vertically hanging connector. Capillary action encourages the moisture to creep along the sides of the wires, down into the housing where it attacks the metal of the pins and connectors, damaging their electrical conductivity.
When possible, position electrical connector housings horizontally, so rainfall and moisture---even the moisture from a heavy dew--drips off instead of draining into the connector housing. If electrical connectors must be mounted vertically so that there is a risk of moisture invasion, consider smearing a dab of silicone around the harness/connector junction, to seal the connection against moisture. You may cuss that silicone if you ever have to disassemble or replace that connector, but--maybe, if you keep water out of it, you'll never face that problem.