Escapees July-August 2024

Wire Size/Gauge As electricity passes through a wire, it heats up. If the wire is too small for the load, it will get too hot and could melt, or worse, causea fi re. This is why it’s important to size the wiring correctly and to protect with appropriate fuses. American Wire Gauge scale (AWG) is the standard way to measure wire in North America. Both the maximum current (or load in amps) that will run through the wire, as well as the length of the wire between the source and appliance, determine what AWG wire you’ll need in your system. The scale is not intuitive, however, the smaller the AWG number the larger the diameter of wire. See the charts on page 38 for clari fi cation.

Installations Considerations: Wire Color, Type and Gauge

One of the problems that DIYers get into when working on their RV is the confusion about wire colors, types and sizes between AC and DC wiring. When installing an inverter, you’ll be dealing with BOTH types, so it’s important to understand the differ ences. Generally speaking, AC wires can be a smaller gauge than DC wiring at the same current load, so it’s important to limit the length of any DC run and maximize the AC (see wire charts). As always, if you don’t feel comfortable with electrical wiring, consult a licensed electrician. Wire Color and Type Color coding is important to follow so that you or any other technician can easily deter mine the wiring in your system. The chart below refers to wires in a DC or AC circuit. DC wire can be single-strand or a braided copper wire made from many strands and coated in an insulating plastic. AC wire, like the kind used in homes, is often referred to as Romex (a popular brand name) or NM (non-metallic), which consists of three to four individual copper wires coated with insu lated and color-coded plastic and bundled in an insulated sleeve.

DCPower (typically 5V-12V)

ACPower (typically 120V-240V)

Red

Positive (hot) Negative (non-ground)

Black

Positive - Phase 1 (hot) Positive - Phase 2 (hot)

Black

Red

White*

Ground

Blue** White

Positive - Phase 3 (hot)

Neutral Green*** Ground

*Could also be gray. **Typically only used in commercial or very high voltage systems. ***Could also be bare wire.

DCPower

Installations Considerations: Location and Additional Parts

• Proximity to Battery: The inverter should be installed close enough to the battery bank to minimize voltage drop over the length of wire. However, if you are using fl ooded lead acid batteries, do not install the inverter in the same compartment because of the potential for fi re. Flooded lead acid batteries have the potential to off gas during charging and a spark from the inverter circuitry has the potential to ignite the gas. If you are using Gel, AGM, or Lithium Iron Phosphate (LiFePO4) batteries, you can install these in the same compartment because they are all sealed batteries. • Ventilation Space: While doing its work, inverters give off heat and need space, especially around the cooling fan intake vents. Each installation has parameters

POSITIVE (NON-GROUND)

NEGATIVE (NON-GROUND)

GROUNDED

ACPower 120/208/240V

PHASE1

PHASE2

PHASE3

NEUTRAL

GROUND

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July/August 2024 ESCAPEES Magazine