DC electronics safety notes
* Why are we talking about this?
* Personal safety
* Fire safety
* Preventing catastrophic equipment failure
* Wire gauge - sizing wire correctly
* Measured in AWG, bigger numbers are smaller wire
* Many wire manufacturers will provide an "ampacity" chart to talk about current rating in various wire products.
* Wire construction
* Stranded wire is easier to work with generally but isn’t as good of a conductor as solid wire. Stranded wire is also best for applications where the cable is expected to bend and move.
* Solid wire is harder to work with but has higher durability and is a better conductor than stranded wire. It’s best for applications where the cable won’t be moving a lot such as fixed installations and is generally cheaper.
* Copper wire is more expensive and is a better conductor of electricity and tends to be more durable.
* Aluminum wire is half as heavy but requires heavier gauges to carry the same amount of current as copper wire.
* Sizing wire to not be the thing that gets hot when a short circuit occurs.
* Overgauging for expected load relative to fuses or breakers to ensure the wire isn't the thing that heats up and burns.
* Fuses and breakers
* Why fuses?
* Burn out and stop the flow of current with a fusible link.
* Affordable
* Keep spares
* Why breakers?
* When the heat of an internal element is too high the circuit is broken by an element. Circuit breakers can be reset.
* More expensive than fuses.
* Automatically resetting circuit breakers exist, but many are manual and can be used as a switch to turn sources of electricity off.
* Note: When building DC systems make sure circuit breakers are explicitly rated for DC systems. AC breakers aren't an acceptable substitute here.
* Install these items as close to the thing being switched as possible.
* Covering contact points
* Why cover contact points?
* Prevents accidental shorts by having less exposed surface area.
* Cover contact points
* Wire nuts
* Electrical tape
* Heat shrink
* Quality splices (mention marine grade)
* Connectors
* Powerpole
* SAE connectors
* Keeping things dry/sealed
* Because metallic dust and water can potentially short internal parts
* Using and understanding the limitations of various sealed enclosures
* Using properly built installed sealed connectors
* Use cable glands
* Silicon / sikaflex
* Power source disconnects
* Batteries
* Solar panels
* Avoid deep discharge of batteries
* Some sort of monitoring of battery capacity used
* Varies by battery chemistry