Forum Topic

Unified Solar Panels and Controllers Thread (FAQs, DIY Help)

  • I've talked to an insurer before, di ko sure kung Prudential or Malayan. I was asking how they would insure my pv system and mostly compliance ang kailangan nila down to the rating of the smallest wire. Since the same is needed by the city engineers for net metering purposes, there should be no problem.

    What I remember disagreeing with was the valuation of the insured system. Kasi may sarili silang depreciation which if I remember correctly yung value was way below what the value of the system would be in five-ten years. Maybe because this was more than two years ago and they have no experience with the correct valuation or they foresee solar becoming cheaper as the tech advances, I don't know.

    What I do remember specifically was how they would treat solar additions to an existing insured house. If the cause of a claim was a fire, and there was an undeclared and/or uninsured pv system, no matter what the investigation says, the claim could be denied due to the added risk of the pv system not being factored in when the policy took effect. Ang analogy was an insured helicopter flying with fuel containers. Pag lumabas sa investigation yun in the event of a crash, automatic breach of policy siya whether or not the fuel caused the crash or the succeeding fire, if any.
  • Bakit kaya 13v ang output voltage ng SCC 12v setup ko? Plano ko din kasi ikabit ang Skydirect digibox 12v, okey lang kaya yun kahit 13v ang SCC output? Salamat
  • Ano po ba make and model ng scc nyo?
  • ^ CM5024Z yung galing kay daking.
  • Mga sir any review sa NPP battery?? Mga ilan taon kaya itatagal nito? Ung motolite solar master kasi di talaga maganda..thanks in advance sa sasagot.
  • Yung 200 ah na npp ko in use since 2014, oks pa naman hanggang ngsyon.
  • Baka madalas ma deep discharge yung solarmaster nyo sir, or baka kailangan i-top off ng tubig (?)
  • Yung 200 ah na npp ko in use since 2014

    sir, ilang piraso po ung npp nnyo at anong volts setup nya? thanks po
  • isa lang po, 12 volts. Being charged by a 300 watt panel + mppt scc. Tapos sa gabi nakatop off using a 12v suoer battery charger or pede din gamitin ko sa gabi. Pero mas prefer ko na gamitin sa umaga.
  • 200ah battery charging at 300w panel, dpo ba maliit ang ratio ng charging? definitely png araw lng talaga na gamit.

    ask ko na din, ung Tomzn 63a ayaw ng lumipat sa reserve ksa automatic pro manual ok nmn sya preho. marepair pa kaya ito me 1 yr nrin ata sya. parecommend nrin sna ng fast switch na ATS, eto ksing Tomzn pgswitch namamatay ung ibang ac appliances.. thanks po ng mrmi.
  • Bakit kaya 13v ang output voltage ng SCC 12v setup ko? Plano ko din kasi ikabit ang Skydirect digibox 12v, okey lang kaya yun kahit 13v ang SCC output? Salamat


    dahil "charge" controller ang SCC upang magampanan nya ang kayang tunkulin para mag charge dapat itong makapag bato nang mas mataas na voltahe sa battery. Amps will be affected if no flow is achieved. no flow means yung difference nang voltage, the higher the difference the higher the amps.

    ang mga DC gadgets kasama digibox may say 12v ang adaptor nya pero in reality may range yan na maaring +-1 to 2 volts pero wag itong hulaan dahil baka masira. unless may info or test i dont suggest going to high a voltage. ang suggestion ko is gamit ka nang 12v stable circuit o converter e.g. accepts 5v to 24v but output is stable 12volts. saka never put a load sa SCCM na walang battery. yung battery acts as a voltage limiter.
  • ^ maraming salamat.
  • 200ah battery charging at 300w panel, dpo ba maliit ang ratio ng charging? definitely png araw lng talaga na gamit.
    pwede nga 300W charging a 1200AH battery bank or more... depende yan sa design ng system mo... yung mga ratio na yan eh para lang yan malaman kung ilan ang kayang icharge for 1 day ng panel. Eh paano kung walang araw (bagyo o kaya low pressure) nga naman sabi ni panot... eh aasa ka sa backup mo which is yung sobrang capacity ng battery bank mo. Pagbalik ng araw eh unti unti na yang magcharge.
  • Bakit kaya 13v ang output voltage ng SCC 12v setup ko? Plano ko din kasi ikabit ang Skydirect digibox 12v, okey lang kaya yun kahit 13v ang SCC output? Salamat
    may sinasabing nominal voltage ibig sabihin nun may range ang working voltage at para madali eh nilabel nila sa pinakalamapit sa gitnang whole number ng range na yun.

    unless may info or test i dont suggest going to high a voltage. ang suggestion ko is gamit ka nang 12v stable circuit o converter e.g. accepts 5v to 24v but output is stable 12volts. saka never put a load sa SCCM na walang battery. yung battery acts as a voltage limiter.
    Disagree ako ng konti dito... pwede niyang gamitan ng 13V yung 12V TV niya kasi una sa lahat... negligible ang electronics na walang tolerance at safety factor lalo na sa medical electronics at yung grabe ka specialized na .001 ang tolerance eh nag eexists lang yan sa Laboratories or companies na gumagamit ng precision instruments...example laser.
  • ^ ganun po ba. Salamat
  • @olhr

    Hindi po ako sure pero meron arrow (triangle) sa lower right na naka turo <<

    Same pa din po kahit ngayung araw, nasa 1800w napoproduce ng Solar Panels, na confirm ko na yung number sa lower left ng Digital Meter screen is yung current usage, so nag monitor po ako bawat bukas ng appliance, computer etc, nababawasan yung number hanggang maging nasa 1.3kw/h yung nandun so meaning po diba dapat walang dadagdag dun sa cumulative reading. After 1 hour, nadagdagan ng 1 yung reading nya even though alam na alam ko na yung reading doon is energy supplied back to the grid and hindi yung ginagamit namin.

    Edit : Contacted both our Solar Provider and ERC to get more opinions.

    Edit 2 : So it turns out na Uni-directional daw yung installed na meter or something. So either daw magbayad ako for Net Metering para hindi ko daw kelangan bayaran yung binabalek kong kuryente or gamitin ko daw yung binabalek kong kuryente. What?

    -- edited by ConiPa on Feb 15 2019, 03:06 PM
  • Meaning nyan mag apply ka ng netmetering or magdagdag ng load o kaya evil plan...magpalit ng multidirectional smart meter. Hehehe
  • So it turns out na Uni-directional daw yung installed na meter or something. So either daw magbayad ako for Net Metering para hindi ko daw kelangan bayaran yung binabalek kong kuryente or gamitin ko daw yung binabalek kong kuryente. What?


    ibigsabihin na kahit over produce ka lumalabas kumokonsumo ka parin. imbis na nakatipid, sinisingil pa parin nang meralco na kala mo sakanila ang na produce mo. example: load mo 1kw pero produce mo 2kw, edi over produce ka na 1kw, mangyayari 1kw singil sayo na dapat ay 1kw utang nang meralco.

    ganyan rin metro ko eh, dahil old house yung bahay namin hindi ako pwede lagyan nang netmeter, so ginawa ko, if over produce walang iababalik sa meralco. setting ko lang sa inverter ko na produce lang based on load.
  • Pa recommend po ng sulit na solar street lights, plano ko ilagay sa likod bahay namin. Salamat!
  • Kaya important talaga ang limiter pag walang net metering.
    Yung grid tied setup ko nilagyan ko ng 2 batteries, kasi nang hihinayan ako sa sobrang kuryente na kayang iproduce ng PV. Auto On ng 7am, auto Off ng 9pm.
  • Here's a good discussion topic:

    Given A) A limiter prevents backfeeding into the grid when production is more than consumption.

    Given B) A generator connected to a grid-tie inverter when the grid is down will be in danger of being backfed excess energy harvested by the panels.

    Doesn't this mean that a limiter should suffice in allowing your grid-tie to continue operating and supplementing your generator output?

    I haven't found a clear discussion about this topic apart from the generator being a voltage source and the gti being a current source. Because if a limiter can solve this problem, then all I need would be that plus a generator when the grid is down instead of costly batteries and hybrid inverters.
  • @rancor

    Are we assuming the limiter is a separate device from the inverter or one of those inverters that have a limiter function as well?

    Maybe Its not technical but the business side of it.

    Most grid-tied inverters, are listed UL 1741 which means that they are equipped to detect line voltage from the grid and to shut down when this voltage is lost to prevent them from backfeeding into the grid. This called anti-islanding and it is meant to protect linesman who could be servicing the utility from harm. If a grid-tied inverter were feeding into the grid while the linesman is working on the power lines that person could be seriously injured or worse.


    From the above, i would think it has to do with the UL certification. Certification that is needed to be able to sell in different markets. Yes putting a limiter should prevent back feeding into the grid but what if someone doesn’t have one. It could cause major harm. So manufacturers probably did the simplest thing which is to just shutdown if the inverter can’t detect grid power. Sure some inverter could still operate but correct me i’m wrong, those are hybrids and cost more.

    So if they want to produce affordable inverters to meet certain certifications then that would be the route they chose.

    Now what if a market does not need that kind of certification. They still wouldn’t do it because their inverters can travel cross border and unscrupulous individuals may sell them to unknowing customers (how many of us really try to find out what the UL certification means). This might get their product banned; this will open them to lawsuits, penalties and fines; worse if someone dies, criminal liability.

    So from a manufacturing and safety point of view that would be my opinion.

    UL is but one standard, there are also several others like iec, tuv, etc.

    -- edited by wmaxell on Mar 06 2019, 10:58 AM
  • You misunderstood my two givens. The scenario focuses on using limiters--whether built-in or not--alongside portable generators when the grid is down to prevent the panels and inverter from backfeeding to the generator. There's very little discussion I have found which touches on the subject and the most that I found is the incompatibility between the pv inverter being a current source and the generator being a voltage source.
  • You misunderstood my two givens. The scenario focuses on using limiters--whether built-in or not--alongside portable generators when the grid is down to prevent the panels and inverter from backfeeding to the generator. There's very little discussion I have found which touches on the subject and the most that I found is the incompatibility between the pv inverter being a current source and the generator being a voltage source.


    Its not as simple as that,
    1. A limiter works by attaching a CT clamp that measure AC current going from the grid to the loads. If more current is going in, the grid tie inverter increases AC production to feed the loads. It does not measure the current draw from the loads directly. Conversely if there is less inflow of current from the grid, it throttles back AC production to prevent excess AC going to the grid.

    2. Grid tie inverters dont have a seperate AC "OUT". (Only hybdrid inverters have it) Grid tie inverters only has AC "IN" where it gets power to power itself and where it dumps AC generated by the PV to the household loads and the excess to the grid. (Hence the limiter). You will then have to connect the generator to this AC "IN" as well if you want it to power it using the generator. Since the inverter's limiter is monitoring grid power and not the generator it will not throttle its production back and would still backfeed the excess to the generator with catastrophic result.
  • Since the inverter's limiter is monitoring grid power and not the generator it will not throttle its production back and would still backfeed the excess to the generator with catastrophic result.


    This is the part that baffles me. Assuming the generator is tapped into the main breaker going into the house but is disconnected from the grid, how is the inverter/limiter able to tell that it is not grid power and prevent throttling down production to prevent backfeeding?

    Ex:
    Meralco -> main breaker -> limiter -> inverter
    Generator -> main breaker -> limiter -> inverter
    From a layman's pov, there shouldn't be a difference in preventing a backfeed.

    But
    If more current is going in...

    Is this the key difference? This is where most discussion I've found states that the generator is a voltage source. And no one has yet ELI5 the difference with respect to the proposed setup above.
  • Spoke too soon.

    I finally found a source which explained that while the scenario posted above should work theoretically, the inverter's anti-islanding would only allow a smooth operation in rare cases specifically relying on how good your generator is (if it provides "clean" output).

    Basically, when???? the load changes suddenly, the voltage will change, even if? just momentarily. And when the voltage ?cha?nge?, because of all sorts of laws that says the total energy? must stay the same, the frequency must change ?too, even if just subtly. So even with an electronic gen?erator?, islanding equipment still use the same technique?s.


    The way I understood this is that generator engines run as slow or as fast as the demand requires so long as it is within the capacity. But if the demand is not constant, the subtle change in the demand triggers the necessary frequency adjustments that then trigger the inverter's anti-islanding features.

    The limiter can do the job as proposed above, but for it to work as closely as a grid substitute, your generator cannot be your standard, portable and AFFORDABLE emergency generator. Which defeats the purpose of trying to avoid expensive battery backups.

    Side note: California, Germany and Australia are not the only areas with thriving solar forums. I found my info from a South African forum I never thought of checking before.

    To end, for those who may be wondering, no you cannot simply buy a generator from Ace, plug it in to your grid during a blackout and expect your pv to work even if you have a limiter.
  • Also if I may add there is a split second backfeed to the grid caused by the delayed reaction by the inverter as it throttles down it's AC production when it receives the signal from the CT sensor. I see this in my system as the Meralco meter turns backward a bit before moving forward again. This usually happens when a heavy load usually an air conditioner in my house is suddenly turned off and the inverter is producing lots of power. I don't think a generator will take too kindly to the sudden onrush of current equivalent to thousands of watts even for a split second when a heavy load is turned off.
  • Mga kasolar, summer is near and simula na ang fire prevention month. Saating Mga DIY sana po tayo ang manguna sa safety.

    Check list:
    1. gaano ka protectado ang inyong wiring alaban sa tubig at init?
    - mainit na yero nang bubong, kaya tumunaw nang plastic ng wires, gumagamit ba kayo atleast nang pvc pipes para maipaluob ang wires nyo, sana hindi po ito yung rumurupok.
    - gumagalaw nang wires, maaring maka sugat sa wires.

    2. over sizing. nasanay tayo maulap, ngayon tag init, maaring lumagpas sa normal rating ang inyong panels, sana ito ay properly sized meaning, wire size, fuse size..etc

    3. panahon na nang mag linis nang panel - alikabok at tubig ang kalaban nang panel.. mag ingat at baka madulas.

    4. check your batteries - sa mga may battery backup, check your water levels at connections. sparks during charging may ignite the hydroxy gas.

    5. para tumagal ang mga components e.g. controller, breakers...etc checkin na ito at hindi maalikabok, mga fans ay maganda ang ikot kung meron, mag down nang system at check na freely moving ang mga breaker

    ..marami pang iba. =) happy and safe summer sa lahat.
  • ^+1M, thanks bro.

    just replaced my old ats to a fast switch [email protected] dina kasi ng switch pakabila ung luma ko. 1st 3days ok naman ung fast switch as in walang glitch at dna namamatay ung tv, pc and other appliances. on the 5th day bigla syang pumutok black out lahat. itinawag ksa pinagbilhan ko and wow they offered me an replacement plus free shipping. 1st time daw cla nkaencounter ng ganun at aalamin sa supplier anong cause. i received the replacement and 2wks now at stable na sya. btw, nka timer at remote control setup ung ats switch ko.
  • How many hours will a motorcycle battery lasts, If I use it on A desktop with 600watts power supply ?