Fuse only the hot wires, and size the breaker to the wire
In a four-conductor 240 V circuit (two hots, neutral, ground), fuses or breakers go only in the hot wires.
Fuse the hots, never neutral or ground. Colours vary: a white wire can be re-marked as a hot.
The breaker must protect the thinnest wire. AWG 14 goes with a 15 A breaker, AWG 12 with 20 A. A lower AWG number is thicker wire. The National Electrical Code covers the electrical safety of the station.
Copper wire drawn to scale. Lower AWG number = thicker wire = more current allowed.
RememberHots only. 20 A needs AWG 12, 15 A needs AWG 14.
GFCIs and interlocks cut the power when something goes wrong
A GFCI trips when current flows from a hot wire directly to ground, for example through you. Current from hot to neutral through a load is normal.
Hot to neutral through the load is normal. Hot to ground is the fault a GFCI catches.
A power supply interlock removes dangerous voltages when the cabinet is opened. It does not sense heat or overvoltage.
The lid holds the interlock switch closed. Lift it and the AC feed is cut.
RememberGFCI: leak to ground. Interlock: cabinet opened.
Ground outside, arrest at the entry, bond everything
Outside, at the entry, all bonded.
Put the lightning protection ground system outside the building. Mount arrestors where the feed lines enter. Bond every ground rod together with all other grounds, so no point rises above the rest during a strike.
RememberOutside, at the entry, all bonded.
Before a climb: lock out the power, check the harness
Lock out and tag the power. Check the harness rating and service life.
Confirm the harness is rated for the climber's weight and within its allowable service life. If the tower supports electrically powered devices, lock out and tag every circuit that feeds it first. Do not unground the tower.
RememberLockout and tag, then a rated, in-date harness.
Fumes and lead: ventilate the generator, wash after soldering
Exhaust gas is poisonous. Lead from solder rides on your hands.
Run an emergency generator in a well-ventilated area. Do not store fuel next to it. The danger from lead-tin solder is lead contaminating food if you do not wash your hands.
RememberGenerator: fresh air. Solder: clean hands.