How to monitor a small home PV plant ?

srhill
srhill Registered Users Posts: 8
Hi everyone,
I have been trying to figure out how to monitor my new PV plant I am installing. The more I look at the SMA options the more confused I get. I will be monitoring a SB8000 inverter. Has anybody got a recommendation ?
I have a 400 foot distance from the array / inverter to the house and would like to lay the proper com wire at the same time I do the electrical, and of course I would like to see lots of data and charts....
Thanks to all.

Comments

  • solar_dave
    solar_dave Solar Expert Posts: 2,397 ✭✭✭✭
    Re: How to monitor a small home PV plant ?

    I monitor mine with a TED 5000 (see signature, it is down now as I have painter here and it is unplug, it will be back later today) the advantage is if you setup right you can monitor the load side as well.
  • vtmaps
    vtmaps Solar Expert Posts: 3,741 ✭✭✭✭
    Re: How to monitor a small home PV plant ?
    srhill wrote: »
    I have a 400 foot distance from the array / inverter to the house and would like to lay the proper com wire at the same time I do the electrical

    Be sure to lay a separate conduit for the com wires. The AC power wires will induce currents in your com wires if they are in the same conduit.
    --vtMaps
    4 X 235watt Samsung, Midnite ePanel, Outback VFX3524 FM60 & mate, 4 Interstate L16, trimetric, Honda eu2000i
  • inetdog
    inetdog Solar Expert Posts: 3,123 ✭✭✭✭
    Re: How to monitor a small home PV plant ?
    vtmaps wrote: »
    Be sure to lay a separate conduit for the com wires. The AC power wires will induce currents in your com wires if they are in the same conduit.
    --vtMaps

    It is hard to go wrong by installing a couple of CAT 5 runs. But the best planning for the future is to put in conduit with only sweeps instead of L section and maybe a pull box access halfway along.
    And by all means put in a pull wire or pull tape at the time you lay it to make sure that you can get additional wires through it someday.

    On the other hand, that is not too great a distance for Internet over WiFi frequencies with only modest directional antennas, so maybe just choosing only equipment with a network interface would be a better way to go as long as you have a clear line of sight.
    SMA SB 3000, old BP panels.
  • stephendv
    stephendv Solar Expert Posts: 1,571 ✭✭
    Re: How to monitor a small home PV plant ?

    You can buy an additional RS485 "piggyback" module which is installed in the SB and then use CAT5 to connect this to a sunny webbox for example. If you don't want the sunny webbox you could also build your own DIY solution with a USB RS485 adapter and freely available software (e.g.: http://users.coditel.net/vdeconinck/smysqlogger/index_en.xhtml )

    SMA also offer an RS485 wireless set: http://www.sma.de/en/products/monitoring-systems/wireless-set-485.html but it isn't on the US website, so might not be available.
  • Surfpath
    Surfpath Solar Expert Posts: 463 ✭✭✭
    Re: How to monitor a small home PV plant ?
    vtmaps wrote: »
    Be sure to lay a separate conduit for the com wires. The AC power wires will induce currents in your com wires if they are in the same conduit.
    --vtMaps
    Hi Vt,
    A quick related question. Would a DC wire run affect a Cat 5 cable run? I was hoping to run my Mate II cat5 up the same 33mm conduit that my combiner to controller wire runs down (the latter is 110V DC). This same run passes down near a kitchen wall. It'd be great to place the Mate there.
    Outback Flexpower 1 (FM80, VFX3048E-230v, Mate, FlexNetDC) 2,730watts of "Grid-type" PV, 370 AmpHrs Trojan RE-B's, Honda 2000 watt genny, 100% off grid.
  • inetdog
    inetdog Solar Expert Posts: 3,123 ✭✭✭✭
    Re: How to monitor a small home PV plant ?
    Surfpath wrote: »
    Hi Vt,
    A quick related question. Would a DC wire run affect a Cat 5 cable run? I was hoping to run my Mate II cat5 up the same 33mm conduit that my combiner to controller wire runs down (the latter is 110V DC). This same run passes down near a kitchen wall. It'd be great to place the Mate there.
    The DC by itself will not have any effect on the circuits using the Cat 5.

    But if there is switching noise on the DC, as a result of the input circuit of the inverter or CC, then it might be a problem. If you use twisted + and - wires for the run, it will minimize the coupling. The Cat 5 already uses twisted pairs, which will be good if the application using the Cat 5 properly chooses the wires that they use for different purposes.

    You can get a very rough idea of the amount of noise on the DC compared to the AC by bringing an AM radio close to the wires.
    SMA SB 3000, old BP panels.
  • Surfpath
    Surfpath Solar Expert Posts: 463 ✭✭✭
    Re: How to monitor a small home PV plant ?
    inetdog wrote: »
    You can get a very rough idea of the amount of noise on the DC compared to the AC by bringing an AM radio close to the wires.
    Nice tip. Thanks! It's good to know the difference. -SP
    Outback Flexpower 1 (FM80, VFX3048E-230v, Mate, FlexNetDC) 2,730watts of "Grid-type" PV, 370 AmpHrs Trojan RE-B's, Honda 2000 watt genny, 100% off grid.