missing mc4 connectors

alcatel99
alcatel99 Registered Users Posts: 31 ✭✭
I have just been to visit a neighbour 18 miles away and he showed me his new solar system which appears to be all good with well known products only thing i did not understand was he did not have any mc4 connectors on his panels or on extended cables he just has them soldered and shrink wrapped he says he was told that the mc4s can reduce power 
i have never heard of this, his system is working good and he seems happy ,so has anyone ever heard of this.

Comments

  • mike95490
    mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    Damaged or improperly handled MC4 connectors can reduce power.   And many folks in ignorance, have likely damaged them by connecting / disconnecting under load, leaving unconnected and exposed to weather, or rough handling and breaking the weathertight seals.

    Soldered and heat shrink works too, but becomes clumsy when repair/inspection/diagnosis is needed.
    Powerfab top of pole PV mount | Listeroid 6/1 w/st5 gen head | XW6048 inverter/chgr | Iota 48V/15A charger | Morningstar 60A MPPT | 48V, 800A NiFe Battery (in series)| 15, Evergreen 205w "12V" PV array on pole | Midnight ePanel | Grundfos 10 SO5-9 with 3 wire Franklin Electric motor (1/2hp 240V 1ph ) on a timer for 3 hr noontime run - Runs off PV ||
    || Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
    || VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A

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  • Photowhit
    Photowhit Solar Expert Posts: 6,002 ✭✭✭✭✭
    alcatel99 said:
    I have just been to visit a neighbour 18 miles away and he showed me his new solar system which appears to be all good with well known products only thing i did not understand was he did not have any mc4 connectors on his panels or on extended cables he just has them soldered and shrink wrapped he says he was told that the mc4s can reduce power 
    i have never heard of this, his system is working good and he seems happy ,so has anyone ever heard of this.
    Soldered and not crimped connections are not code compliant! Must be crimped first and still with wires subject to even gentle movement the solder creates a fulcrum point for connections to fail.

    There is a very slim chance to have problems with MC4 connectors unless, and to a degree even with, poor handling.
    Home system 4000 watt (Evergreen) array standing, with 2 Midnite Classic Lites,  Midnite E-panel, Magnum MS4024, Prosine 1800(now backup) and Exeltech 1100(former backup...lol), 660 ah 24v Forklift battery(now 10 years old). Off grid for 20 years (if I include 8 months on a bicycle).
    - Assorted other systems, pieces and to many panels in the closet to not do more projects.