Solar Panel connectors - MC4 and replacements

Sak_newhereSak_newhere Registered Users Posts: 11 ✭✭
Hey everyone, 

I am relatively new to this field and was hoping to get some help.

I have a few questions about the MC4s and their ideal replacements. I read the discussions about the MC4s, pros, cons in many forums and I don't want to go for them. I checked about Anderson Power Pole and few others but they don't seem to fit in my scenario. I was wondering if there are any ideal replacements for the MC4 Y connectors? The entire setup would be used on an EV (around 6 - 10 panels) therefore, should be able to withstand extreme conditions, vibrations etc. Any suggestions would be highly appreciated. 

Many Thanks!

Comments

  • littleharbor2littleharbor2 Solar Expert Posts: 1,482 ✭✭✭✭
    Buy or build a combiner box. Here's a basic one.

    2.1 Kw Suntech 175 mono, Classic 200, Trace SW 4024 ( 15 years old  but brand new out of sealed factory box Jan. 2015), Bogart Tri-metric, 700 ah @24 volt AGM battery bank. Plenty of Baja Sea of Cortez sunshine.

  • Sak_newhereSak_newhere Registered Users Posts: 11 ✭✭
    edited November 2019 #3
    Hey mate,

    Thanks a lot for the reply. It is pretty much interesting and I have a direction now. But I forgot to mention that I have some constraints when it comes to the dimensions. The height of the connector/combiner box should just be 1.5 cm including the casing if needed for the ambient resistance. The length and breadth wouldn't matter that much. I went through Dinkle power boxes and I reckon that the height of any combiner box when placed horizontally or vertically would be more than that. This was the reason to go for MC4 Y in the first place. Are there anything that could fit in this bracket? 

    Thanks!
  • littleharbor2littleharbor2 Solar Expert Posts: 1,482 ✭✭✭✭
    edited November 2019 #4
    I think you could build one from scratch, although probably not with integrated fusing. There are inline fuses you can use. Using these you can combine with MC-4 branch connectors. Once you combine 3 or more panels they need to be individually fused.



    2.1 Kw Suntech 175 mono, Classic 200, Trace SW 4024 ( 15 years old  but brand new out of sealed factory box Jan. 2015), Bogart Tri-metric, 700 ah @24 volt AGM battery bank. Plenty of Baja Sea of Cortez sunshine.

  • Sak_newhereSak_newhere Registered Users Posts: 11 ✭✭
    Thanks mate! I don't want to use the MC4s, therefore, I will check on how I could build a combiner box. Thanks a lot! 
  • Sak_newhereSak_newhere Registered Users Posts: 11 ✭✭
    edited November 2019 #6
    I was wondering if there are any Anderson Power Pole connectors / other connectors that combines multiple input strings and delivers a single output pair which could be coupled with the solar panels (other than MC4s). I found one website link that gives a similar product (3 in 1 Power Pole) but couldn't find any other similar products that combines multiple input strings and delivers a single output pair. 

    https://www.grandado.com/products/3-in-1-50a-12v-anderson-connector-harness-stekkerconnector?variant=15896725192798&currency=EUR&gclid=Cj0KCQiA5dPuBRCrARIsAJL7oejGwui9tAE1cghtzIUWqzyOM6vEE1AI0wuKI3i_npdI4J8NzsCfIAAaAgdOEALw_wcB


  • BB.BB. Super Moderators, Administrators Posts: 30,037 admin
    You can find some various Power Pole assemblies in HAM radio stores:

    https://www.mfjenterprises.com/Product.php?productid=MFJ-1106

    But I am not sure I would go down that route. Cutting off and wiring up with new weather proof or simply crimp splices with a few wraps of self vulcanizing tape, a few wraps of plastic electrician's tape, and a coating of 3M sealant... That is what we did on shipboard electronics/wiring connections exposed to weather (and even with radio antenna connectors)--Of course, took all the tape off once every year or so, inspected, and re-sealed.

    But I doubt anyone would want to do that... Our host has various combiner boxes (just cut wire ends, and MC4)...

    https://www.solar-electric.com/search/?q=combiner+boxes

    I would not suggest Anderson Power Pole connectors for exterior connections... (the ones I am aware of) Power Pole is not water/weather tight, and you would need to install them in weather tight a J-Box with drip loops, etc. anyway.

    Y connectors can work for smaller system (just a few panels)--But more than that, really need a combiner box of some sort (even just a utility AC distribution panel, "wired backwards" (circuit breaker protected branch circuits to panels, main buses to charge controller).

    Of course, you have to have the right DC rated breakers for such a panel too...

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • photowhit_crapphotowhit_crap Registered Users Posts: 3
    I was wondering if there are any Anderson Power Pole connectors / other connectors that combines multiple input strings and delivers a single output pair which could be coupled with the solar panels
    Not sure why you want to reinvent the wheel. Anderson  connecters are not water tight,  I would not use them where they were not intended.

    Have you seen massive failures in MC4 connectors? I can't  recall a  failure in 100 or so panels I've installed. We get plety of vibration with 60+  mph winds and 17 inches of snow last year. 


    If  you do find a replacement, be sure that the wiring is designed for UV protection.
  • Sak_newhereSak_newhere Registered Users Posts: 11 ✭✭
    BB. said:
    You can find some various Power Pole assemblies in HAM radio stores:

    https://www.mfjenterprises.com/Product.php?productid=MFJ-1106

    But I am not sure I would go down that route. Cutting off and wiring up with new weather proof or simply crimp splices with a few wraps of self vulcanizing tape, a few wraps of plastic electrician's tape, and a coating of 3M sealant... That is what we did on shipboard electronics/wiring connections exposed to weather (and even with radio antenna connectors)--Of course, took all the tape off once every year or so, inspected, and re-sealed.

    But I doubt anyone would want to do that... Our host has various combiner boxes (just cut wire ends, and MC4)...

    https://www.solar-electric.com/search/?q=combiner+boxes

    I would not suggest Anderson Power Pole connectors for exterior connections... (the ones I am aware of) Power Pole is not water/weather tight, and you would need to install them in weather tight a J-Box with drip loops, etc. anyway.

    Y connectors can work for smaller system (just a few panels)--But more than that, really need a combiner box of some sort (even just a utility AC distribution panel, "wired backwards" (circuit breaker protected branch circuits to panels, main buses to charge controller).

    Of course, you have to have the right DC rated breakers for such a panel too...

    -Bill
    Hey Bill,

    Thanks a lot for the suggestions. I have also read that the APPs are not water resistant but was wondering if I can use some body covers of the company-make (Anderson Power Products) to shield the connector. Just curious!!! 

    I have already gone through the combiner boxes but I have some tolerance level / constraints when it comes to my design. The combiner box can easily go upto 10 cm of height whereas I have a minimum allowable limit of just 2 cm, hence my interest lies in connectors like APPs etc.., If I don't find any replacements, I will find a way to use a combiner box. Cheers!

    When you say 'Y' connectors, do u mean MC4 Y?

    Regards,
    Sakthi,
  • Sak_newhereSak_newhere Registered Users Posts: 11 ✭✭
    I was wondering if there are any Anderson Power Pole connectors / other connectors that combines multiple input strings and delivers a single output pair which could be coupled with the solar panels
    Not sure why you want to reinvent the wheel. Anderson  connecters are not water tight,  I would not use them where they were not intended.

    Have you seen massive failures in MC4 connectors? I can't  recall a  failure in 100 or so panels I've installed. We get plety of vibration with 60+  mph winds and 17 inches of snow last year. 


    If  you do find a replacement, be sure that the wiring is designed for UV protection.
    Thanks for the suggestions. There may be advantages of MC4s but I am trying to find a replacement for my design. Having said that, which brand of MC4 do you recommend ?

    Thanks mate!
  • BB.BB. Super Moderators, Administrators Posts: 30,037 admin
    Using Y (including MC4 Y) connectors in power systems are always difficult to do "safely". N+1 power supplies (lots of paralleled power supplies) and distributing power from a central bus to multiple locations almost always require fuses/circuit breakers to reduce the chances of fire from a short circuit/over current event.

    About the only way to avoid using a bunch of breakers/fuses is to design "all the wiring" in a branch circuit to carry the maximum amount of current available from the energy source(s). But this is an expensive (lots of $$ copper) and heavy/awkward solution (working with heavy/stiff copper wiring where only a small diameter cable is needed for the actual current flow).

    -Bill

    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • BB.BB. Super Moderators, Administrators Posts: 30,037 admin
    Regarding your question of which brand(s) of MC4 connectors... It has been too many years since I have been out of industry using connectors to give you a good answer.

    Also, MC4 connectors are (I guess) copyrighted/patented and cannot be made by "anybody"... So you end up with MC4 connectors that are close, "compatible", or look about the same but not compatible. And getting bulk MC4 connectors seems to be less than easy to find too.

    Call up your supplier and see what they sell/recommend. Or perhaps some other folks here can give you the current answer.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • icarusicarus Solar Expert Posts: 5,400 ✭✭✭✭
    edited November 2019 #13
    ^Actually, Amazon is filled with MC4 connectors and tools:  

    https://www.amazon.com/PowMr-Pairs-Mc4-Solar-connectors/dp/B07R8BXH6B/ref=sr_1_1_sspa?keywords=Mc4+solar+connectors

    Can’t speak to the “authenticity” of any of these, but I have bought many and they all seem to work just fine, if you have the proper crimping tool.  

    T
  • PhotowhitPhotowhit Solar Expert Posts: 5,103 ✭✭✭✭




    Thanks for the suggestions. There may be advantages of MC4s but I am trying to find a replacement for my design. Having said that, which brand of MC4 do you recommend ?
    I  don't  know about the connectors, I  purchased 50 sets or so many years  ago and they have worked  fine for me,  I have read about people buying ones  they  were not happy with,  I think   most often when  people  have stated  that here  they were trying to mate MC4 connectors with Tyco(?) connectors  another type of  waterproof connectors  which  look similar.

    Still  haven't heard of any problems you have had with the connectors, or if you have had any problems.

    I   would suggest  a couple think in  using  MC4 connectors, Do not use a single hinge  design  crimper,  they don't  work  well. I have one purchased (dearly) many years ago and  would  replace  it    if   I was doing any large job  again.  The  make  an anvil type  crimper   today that costs less than half of what  I paid  and replicates  the action of the UL crimps  very closely.

    Anvil type crimper, where  the action goes straight  up and down;

    Picture 5 of 12
    I   would  also be careful about what type of wire you buy to use the connectors on. The selection of  UV  protected wire  is pretty  slim, USE2 wire is almost  or  always 7 strand and   difficult  to crimp.  I  did my first array solely with USE 2 wire and basically I just clipped  1 strand and hand  fed the 3 strands into each side of the crimp. This made   a quick job  very tedious and time consuming, but it was the only way I could get a good crimp. PVwire  is  19 strands and much easier to get a  proper crimp! Back  to a quick job!

    If you buy premade wire,  check it! I bought some  because it was cheaper  per foot than I could  find. I had  to cut off the  soldered connecters and do my own.  The were  MC4 connectors, but not  designed for crimping and had been soldered only. Not good for a wirethat will hve constant micro vibrations from wind and rain.
    Home system 4000 watt (Evergreen) array standing, with 2 Midnite Classic Lites,  Midnite E-panel, Prosine 1800 and Exeltech 1100, 660 ah 24v ForkLift battery. Off grid for @16 of last 17 years. Assorted other systems, and to many panels in the closet to not do more...lol
  • Sak_newhereSak_newhere Registered Users Posts: 11 ✭✭
    BB. said:
    Regarding your question of which brand(s) of MC4 connectors... It has been too many years since I have been out of industry using connectors to give you a good answer.

    Also, MC4 connectors are (I guess) copyrighted/patented and cannot be made by "anybody"... So you end up with MC4 connectors that are close, "compatible", or look about the same but not compatible. And getting bulk MC4 connectors seems to be less than easy to find too.

    Call up your supplier and see what they sell/recommend. Or perhaps some other folks here can give you the current answer.

    -Bill
    Hello Bill,

    Rightly said! One of the best options as you stated is to have a conversation with the supplier for better understanding of the compatibility with the tail end connection of the solar panel and choice of the MC4. If I am choosing to go with the connectors, I have certain pre-written pointers to carefully select like the choice of company, crimping tool and certain conventions with regards to mounting etc. So, thanks a lot for the messages :)

    Regards,
    Sakthi.
  • Sak_newhereSak_newhere Registered Users Posts: 11 ✭✭
    icarus said:
    ^Actually, Amazon is filled with MC4 connectors and tools:  

    https://www.amazon.com/PowMr-Pairs-Mc4-Solar-connectors/dp/B07R8BXH6B/ref=sr_1_1_sspa?keywords=Mc4+solar+connectors

    Can’t speak to the “authenticity” of any of these, but I have bought many and they all seem to work just fine, if you have the proper crimping tool.  

    T
    Thanks! hahaa.. Yes, I have also checked amazon and could find a lot of MC4s. As stated in the previous message to Bill, I will follow the guidelines that I have, if I am going with MC4s. 
  • Sak_newhereSak_newhere Registered Users Posts: 11 ✭✭
    Photowhit said:
    Thanks for the suggestions. There may be advantages of MC4s but I am trying to find a replacement for my design. Having said that, which brand of MC4 do you recommend ?
    I  don't  know about the connectors, I  purchased 50 sets or so many years  ago and they have worked  fine for me,  I have read about people buying ones  they  were not happy with,  I think   most often when  people  have stated  that here  they were trying to mate MC4 connectors with Tyco(?) connectors  another type of  waterproof connectors  which  look similar.

    Still  haven't heard of any problems you have had with the connectors, or if you have had any problems.

    I   would suggest  a couple think in  using  MC4 connectors, Do not use a single hinge  design  crimper,  they don't  work  well. I have one purchased (dearly) many years ago and  would  replace  it    if   I was doing any large job  again.  The  make  an anvil type  crimper   today that costs less than half of what  I paid  and replicates  the action of the UL crimps  very closely.

    Anvil type crimper, where  the action goes straight  up and down;

    Picture 5 of 12
    I   would  also be careful about what type of wire you buy to use the connectors on. The selection of  UV  protected wire  is pretty  slim, USE2 wire is almost  or  always 7 strand and   difficult  to crimp.  I  did my first array solely with USE 2 wire and basically I just clipped  1 strand and hand  fed the 3 strands into each side of the crimp. This made   a quick job  very tedious and time consuming, but it was the only way I could get a good crimp. PVwire  is  19 strands and much easier to get a  proper crimp! Back  to a quick job!

    If you buy premade wire,  check it! I bought some  because it was cheaper  per foot than I could  find. I had  to cut off the  soldered connecters and do my own.  The were  MC4 connectors, but not  designed for crimping and had been soldered only. Not good for a wirethat will hve constant micro vibrations from wind and rain.
    Hello,

    Seems like I have to learn a lot about crimping. Thanks for the detailed do's and dont's. From the different conversations I have had so far, I understand that the crimping method and the selection of crimping tool plays an integral part in the mating of the connectors.

    Personally, it is just been few days since I took up the project. My colleagues have been working with MC4s for a very long time and they have had a lot of issues and thus, I am trying to find alternative solutions for the design we have in place. I will explore more on this and get back to you if I have some doubts.

    Thanks,
    Sakthi.
  • garynappigarynappi Registered Users Posts: 68 ✭✭
    I have what you can call a minimal system and found that having an MC4 crimping tool invaluable. Also as mentioned above a solar combiner is a good way to start. I got the pre-wired model below for ~$50 and there was enough room inside to mount two circuit breakers. Also with the MC4's below the box they are shielded from rain. 

     
  • softdownsoftdown Solar Expert Posts: 2,905 ✭✭✭✭

    There are a lot of ways to do connections. All with fans and detractors - pros and cons. There are a lot of ways for a solar installation to fail. I think it is about paramount to have a system voltage readout that you can very easily keep an eye on. Mine involves twisting my head 45 degrees - I'll likely catch a problem on the quicker side.

    First Bank:16 180 watt Grape Solar with  FM80 controller and 3648 Inverter....Fullriver 8D AGM solar batteries. Second Bank/MacGyver Special: 10 165(?) watt BP Solar with Renogy MPPT 40A controller/ and Xantrex C-35 PWM controller/ and Morningstar PWM controller...Cotek 24V PSW inverter....forklift and diesel locomotive batteries
  • Sak_newhereSak_newhere Registered Users Posts: 11 ✭✭
    garynappi said:
    I have what you can call a minimal system and found that having an MC4 crimping tool invaluable. Also as mentioned above a solar combiner is a good way to start. I got the pre-wired model below for ~$50 and there was enough room inside to mount two circuit breakers. Also with the MC4's below the box they are shielded from rain. 

     
    Hey, Thanks for sharing your experience and for the suggestion pal. I have kinda decided to go with designing DIY combiner box. Hopefully, it should come out well. 

    - Sakthi
  • Sak_newhereSak_newhere Registered Users Posts: 11 ✭✭
    softdown said:

    There are a lot of ways to do connections. All with fans and detractors - pros and cons. There are a lot of ways for a solar installation to fail. I think it is about paramount to have a system voltage readout that you can very easily keep an eye on. Mine involves twisting my head 45 degrees - I'll likely catch a problem on the quicker side.

    Hey man,

    Honestly, its been just a month and I have personally learnt a lot from all the different experiences of so many experts here. Irrespective of the pros and cons where it helps in most of the cases, sometimes a design/product that works well for one would not be a right choice for another. 45 !!! I agree on that! hahaaaa, 

    - Sakthi
  • littleharbor2littleharbor2 Solar Expert Posts: 1,482 ✭✭✭✭
    edited December 2019 #22

    Hey, Thanks for sharing your experience and for the suggestion pal. I have kinda decided to go with designing DIY combiner box. Hopefully, it should come out well. 

    - Sakthi
    I have built lots of combiner boxes from scratch. All parts are easy to find on eBay starting with din rail stock and all circuit breakers, fuse holders etc. that work on din rail. There's a a certain satisfaction in building your own combiner. Whether your time is more valuable than the cost of a pre-made one is up to you.

    2.1 Kw Suntech 175 mono, Classic 200, Trace SW 4024 ( 15 years old  but brand new out of sealed factory box Jan. 2015), Bogart Tri-metric, 700 ah @24 volt AGM battery bank. Plenty of Baja Sea of Cortez sunshine.

  • softdownsoftdown Solar Expert Posts: 2,905 ✭✭✭✭

    Hey, Thanks for sharing your experience and for the suggestion pal. I have kinda decided to go with designing DIY combiner box. Hopefully, it should come out well. 

    - Sakthi
    I have built lots of combiner boxes from scratch. All parts are easy to find on eBay starting with din rail stock and all circuit breakers, fuse holders etc. that work on din rail. There's a a certain satisfaction in building your own combiner. Whether your time is more valuable than the cost of a pre-made one is up to you.

    Seems like everyone here is a mcgivor. 
    First Bank:16 180 watt Grape Solar with  FM80 controller and 3648 Inverter....Fullriver 8D AGM solar batteries. Second Bank/MacGyver Special: 10 165(?) watt BP Solar with Renogy MPPT 40A controller/ and Xantrex C-35 PWM controller/ and Morningstar PWM controller...Cotek 24V PSW inverter....forklift and diesel locomotive batteries
Sign In or Register to comment.