Hot plugging and unplugging

Shadowcatcher
Shadowcatcher Solar Expert Posts: 228 ✭✭✭
I have seen warnings not to hot plug/unplug solar panels, which I have ignored. I have used Anderson Power Poles which have a wiping connection good for hot swapping.

Comments

  • Vic
    Vic Solar Expert Posts: 3,208 ✭✭✭✭
    Re: Hot plugging and unplugging

    Sc,

    The advice regarding the MC connectors on PV Modules is good, and should be heeded. If done early in the AM or late PM should not be a problem. DC currents can easily harm contacts when made/broken with reasonable currents flowing. Why tempt fate?

    Believe that the Anderson PPs are not rated for make/break with DC currents flowing. DC easily creates arcs, which can destroy contacts in a single event.

    Again, it is not too dificult to reduce the current flow to zero before making/breaking contact with these connectors.

    just my experience, YMMV, Vic
    Off Grid - Two systems -- 4 SW+ 5548 Inverters, Surrette 4KS25 1280 AH X2@48V, 11.1 KW STC PV, 4X MidNite Classic 150 w/ WBjrs, Beta KID on S-530s, MX-60s, MN Bkrs/Boxes.  25 KVA Polyphase Kubota diesel,  Honda Eu6500isa,  Eu3000is-es, Eu2000,  Eu1000 gensets.  Thanks Wind-Sun for this great Forum.
  • westbranch
    westbranch Solar Expert Posts: 5,183 ✭✭✭✭
    Re: Hot plugging and unplugging

    It's the same reason 'regular' 120 V ac light switches wear out faster when used for DC lights...
     
    KID #51B  4s 140W to 24V 900Ah C&D AGM
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  • waynefromnscanada
    waynefromnscanada Solar Expert Posts: 3,009 ✭✭✭✭
    Re: Hot plugging and unplugging
    westbranch wrote: »
    It's the same reason 'regular' 120 V ac light switches wear out faster when used for DC lights...

    Wear out faster, or, if the voltage and current are enough, totally destroyed by an arc the very first time they're selected to the OFF position.
  • peakbagger
    peakbagger Solar Expert Posts: 341 ✭✭✭
    Re: Hot plugging and unplugging

    My friend hooked up a 3.3 KW system several years ago. It was not practical to cover the panels and he needed to make a connection on the line from the PVs. Rather than waiting until dark (this was the last connection before putting it on line), he started to make the connection. He said the resulting arc was quite impressive and if he does need to work on the system he waits until dark. Sure folks might get awy with it 99% of the time but that 1% is potentially lethal.
  • Shadowcatcher
    Shadowcatcher Solar Expert Posts: 228 ✭✭✭
    Re: Hot plugging and unplugging

    These are two single panels on separate 10ga lines and while they are 40+ volts ea they are hardly a danger. One of the characteristics of power poles is that they shield the contacts from touch. I have some of the bigger 150A Power poles I have used for other purposes.
    My concern was possible damage to the panel not the contacts.
  • Photowhit
    Photowhit Solar Expert Posts: 6,003 ✭✭✭✭✭
    Re: Hot plugging and unplugging

    My panels combine and then come into a DC breaker ahead of the CC, while I don't like to do it, if I need to I'll trip the breaker 1st then work on any MC connections. This should be a 'need to' event as each event weakens the connection, from my sometimes feeble understanding.
    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.
  • boB
    boB Solar Expert Posts: 1,030 ✭✭✭✭
    Re: Hot plugging and unplugging
    My concern was possible damage to the panel not the contacts.

    That won't have any effect on the modules themselves. Just the contacts.

    boB
  • Shadowcatcher
    Shadowcatcher Solar Expert Posts: 228 ✭✭✭
    Re: Hot plugging and unplugging

    Thanks Bob, that is the answer I was looking for. The Anderson Power Poles are for their shear simplicity quite amazing.