alternative to a midnite mini dc

BrianSunBrianSun Registered Users Posts: 9
I've gone to long with disconnects and circuit breakers. It would be nice to buy a MNDC125 and get it all done but I'm cheap. Can I stuff everything into a midnite panel mount type quad box? It says not more than awg 4 wire. I would like to use my 0 gauge battery/inverter wire. I'm looking for a inexpensive box that would hold a couple dc breakers and disconnect.

4- 50W solar panels mounted on a rack mounted to house roof with earth grounding, 15 amp PWM charge control, 2- 100 amh agm batteries, 1000W Wagan Pure Sine inverter.

Comments

  • waynefromnscanadawaynefromnscanada Solar Expert Posts: 3,009 ✭✭✭✭
    Re: alternative to a midnite mini dc

    1500 watt inverter? That's huge for a 200 ah/hr battery bank. You may well be able to extend your battery charge and thus operating time, with a smaller inverter which uses a lot less power just to keep itself running. What are the max loads you have on the inverter? A Morningstar pure sine 300 might very well do all you need, and have a far smaller drain on the battery. 300 watt continuous / 600 surge. Runs a heck of a lot of things all at once in my house, including this computer. It will also start and run the Rello oil burner and circulator pump on my hot water furnace. What bigger loads would you have?
  • vtmapsvtmaps Solar Expert Posts: 3,739 ✭✭✭✭
    Re: alternative to a midnite mini dc
    BrianSun wrote: »
    my system is only used to provide emergency backup for my medical devices cpap, nebulizer etc. nothing critical.
    Welcome to the forum Brian,
    I'm just curious, what would you consider to be critical, if not emergency backup for a cpcp?
    --vtMaps
    4 X 235watt Samsung, Midnite ePanel, Outback VFX3524 FM60 & mate, 4 Interstate L16, trimetric, Honda eu2000i
  • WindsunWindsun Solar Expert Posts: 1,164 ✭✭
    Re: alternative to a midnite mini dc

    A 125 amp breaker is far too large for your setup. I doubt that your equipment pulls anything like 1500 watts - 100 to 250 watts is much more typical. A 1500 watt inverter fully loaded would pull about 131 amps from the batteries, running them down in an hour or so.
  • BrianSunBrianSun Registered Users Posts: 9
    Re: alternative to a midnite mini dc
    vtmaps wrote: »
    Welcome to the forum Brian,
    I'm just curious, what would you consider to be critical, if not emergency backup for a cpcp?
    --vtMaps

    For my condition I could go with out it for a night or two but it would be nice to have. Sorry poor choose of words.
  • vtmapsvtmaps Solar Expert Posts: 3,739 ✭✭✭✭
    Re: alternative to a midnite mini dc
    BrianSun wrote: »
    I've gone to long with disconnects and circuit breakers. It would be nice to buy a MNDC125 and get it all done
    <snip>
    I want to be as close to code and safety as possible.

    Hi Brian, I presume you mean "too long without disconnects and circuit breakers".
    So you want to be close to code? Well, there's lots to discuss. For starters only, do you have a combiner box? Assuming your four panels are hooked up in parallel, you should have a weatherproof combiner box near the panels with each panel having its own fuse/breaker. Take a look at the Midnite combiners.

    --vtMaps
    4 X 235watt Samsung, Midnite ePanel, Outback VFX3524 FM60 & mate, 4 Interstate L16, trimetric, Honda eu2000i
  • BrianSunBrianSun Registered Users Posts: 9
    Re: alternative to a midnite mini dc
    1500 watt inverter? That's huge for a 200 ah/hr battery bank. You may well be able to extend your battery charge and thus operating time, with a smaller inverter which uses a lot less power just to keep itself running. What are the max loads you have on the inverter? A Morningstar pure sine 300 might very well do all you need, and have a far smaller drain on the battery. 300 watt continuous / 600 surge. Runs a heck of a lot of things all at once in my house, including this computer. It will also start and run the Rello oil burner and circulator pump on my hot water furnace. What bigger loads would you have?

    My mistake it is a 1000 watt inverter. The max I have used is 330 watts. With a special from amazon it was $150. It came with a remote, I turn it on and off without going to the garage. The few overnight trial runs have used 20% of the battery's capacity.
  • BrianSunBrianSun Registered Users Posts: 9
    Re: alternative to a midnite mini dc
    vtmaps wrote: »
    Hi Brian, I presume you mean "too long without disconnects and circuit breakers".
    So you want to be close to code? Well, there's lots to discuss. For starters only, do you have a combiner box? Assuming your four panels are hooked up in parallel, you should have a weatherproof combiner box near the panels with each panel having its own fuse/breaker. Take a look at the Midnite combiners.

    --vtMaps

    I used MC4 connector in parallel to a SolaDeck to get the wires through the roof. I have a 15 amp littlefuse to mount in the enclosure. 10 awg wire
  • vtmapsvtmaps Solar Expert Posts: 3,739 ✭✭✭✭
    Re: alternative to a midnite mini dc
    BrianSun wrote: »
    I used MC4 connector in parallel to a SolaDeck to get the wires through the roof. I have a 15 amp littlefuse to mount in the enclosure. 10 awg wire

    Cool. I've not seen a soladeck except on the internet. So you have 4 fuses in it?

    Moving on to the charge controller, from your original post you wrote "Can I stuff everything into a midnite panel mount type quad box?"
    What do you mean everything? Charge controller and inverter and batteries? What is the distance from combiner to charge controller, batteries, and inverter?

    --vtMaps
    4 X 235watt Samsung, Midnite ePanel, Outback VFX3524 FM60 & mate, 4 Interstate L16, trimetric, Honda eu2000i
  • BrianSunBrianSun Registered Users Posts: 9
    Re: alternative to a midnite mini dc
    vtmaps wrote: »
    Cool. I've not seen a soladeck except on the internet. So you have 4 fuses in it?

    Moving on to the charge controller, from your original post you wrote "Can I stuff everything into a midnite panel mount type quad box?"
    What do you mean everything? Charge controller and inverter and batteries? What is the distance from combiner to charge controller, batteries, and inverter?

    --vtMaps

    I would like to have circuit breakers and cut offs for the charge controller, batteries and inverter in one place. The distance between the combiner and charger controller is 40 feet routed through the garage attic and down the wall. The controller to batteries is about 6 feet and inverter is 3 feet. I have a nice little corner where every thing is mounted on the wall.
  • vtmapsvtmaps Solar Expert Posts: 3,739 ✭✭✭✭
    Re: alternative to a midnite mini dc
    BrianSun wrote: »
    I would like to have circuit breakers and cut offs for the charge controller, batteries and inverter in one place. The distance between the combiner and charger controller is 40 feet routed through the garage attic and down the wall. The controller to batteries is about 6 feet and inverter is 3 feet. I have a nice little corner where every thing is mounted on the wall.

    To do it by code requires conduit from your combiner to the panel or box. One way to do it has a battery bus, a ground bus, and an AC bus in one panel/box. You may also have another DC bus for the PV+ wiring. The battery cables run through conduit to the battery bus, and everything connected to that bus (inverter & controller) is through a circuit breaker. The PV output from the combiner goes through a PV disconnect breaker and a DC GFI on its way to the PV+ of the controller. The only bond you can have between the PV- and ground is the GFI. You can bond the AC neutral to ground in this panel if you wish (assuming your inverter permits bonding). That's it in a nutshell... if you wish to wire in the mains or a generator, you will also need a transfer switch.

    As for which midnite panel can hold all of these buses and breakers, I'm not sure if anything smaller than their e-panel will suffice.
    --vtMaps
    4 X 235watt Samsung, Midnite ePanel, Outback VFX3524 FM60 & mate, 4 Interstate L16, trimetric, Honda eu2000i
  • BrianSunBrianSun Registered Users Posts: 9
    Re: alternative to a midnite mini dc
    vtmaps wrote: »
    To do it by code requires conduit from your combiner to the panel or box. One way to do it has a battery bus, a ground bus, and an AC bus in one panel/box. You may also have another DC bus for the PV+ wiring. The battery cables run through conduit to the battery bus, and everything connected to that bus (inverter & controller) is through a circuit breaker. The PV output from the combiner goes through a PV disconnect breaker and a DC GFI on its way to the PV+ of the controller. The only bond you can have between the PV- and ground is the GFI. You can bond the AC neutral to ground in this panel if you wish (assuming your inverter permits bonding). That's it in a nutshell... if you wish to wire in the mains or a generator, you will also need a transfer switch.

    As for which midnite panel can hold all of these buses and breakers, I'm not sure if anything smaller than their e-panel will suffice.
    --vtMaps

    Thank you, I'm going to leave the AC side out for now, no transfer switch. I'll work on the DC side first with the e panel. It looks like the way to go. Thanks for your time.
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