Originally Posted by Martin B.
Solar power seems to have it's own style of wire and fittings. I'd like to know: 1) How #12 awg PV (photo-voltaic) wire is different than other #12 awg wire.
2) Why MC4 connectors are used in solar
wiring rather than other low voltage, high amperage connectors, such as Anderson Power Pole.
Standard #12 AWG building wire comes in solid and stranded and with multiple types of
insulation for different applications IE temperature , voltage , wet or dry locations ,direct burial ,insulation thickness . insulation color and sunlight resistance. Solar
wire is rated for exposure to sunlight , wet locations and solar usage,
IE the conditions the wire will encounter in a solar application and are labeled / listed as such
The MC4 connectors are a code requirement . The terminations are
rated for there usage and provide a disconnecting means for isolating solar panels.
The Anderson power pole connectors are not rated for outdoor use , wet locations ,and have a limited voltage rating .
That being said I used 50 amp Anderson power pole connectors for my portable solar system without issue. The code differentiates little between solar used in a residential /commercial application or an RV application. IE One rule fits all. I would not use Anderson connectors where permanently exposed to the elements where they can degrade . In limited use such as in small portable RV system they probably do not present any major issues.
*Refer to Art 690 of the NEC for clarification*