What's wrong, help needed....

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CBHunter
CBHunter Solar Expert Posts: 39 ✭
in General Solar Power Topics #1
Hello, need some help trying to understand what is wrong here. I'am powering my well pump with my inverter. ( pump is submersible 1/2 hp, draw about 10 amps @ 110vac ) pump is running ok, but after a while when pressure is down, it won't start again. My inverter is still capable of giving me power for other appliances. ( I did a test with my shop Vac ) My batterie voltage is low ( 11,8 volts ) but my inverter doesn't go in shutdown mode yet. If I unplug my pump from my inverter and connect it to the grid, it starts back OK.
Any idea?
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  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    #2
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    Re: What's wrong, help needed....

    Some specs would help diagnose this. Is it a pure sine inverter or modified? How many watts?

    Most likely cause is that when the batteries are low the inverter output is also, especially after the line loss to the pump motor. In other words; not enough voltage at the pump motor to spin it up. Start-up current on these things is tremendous - up to seven times run current, depending on the particular motor. High current + low voltage = pump doesn't run, even though inverter output reads fine.
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  • icarus
    icarus Solar Expert Posts: 5,436 ✭✭✭✭
    #3
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    Re: What's wrong, help needed....

    Marc has it about right.

    As suggested,, the starting load of the pump motor greatly exceeds that of the running load. Factor in line loss to the pump from the inverter and I would guess you would have to low a voltage. Try putting a kill-a-watt (or ammeter) on the pump line and see what it really draws.

    Also realize that the starting load of a shop vac is going to be WAY less,, even if the shop vac is rated ate similar HP.

    Tony

    PS If your battery voltage at rest is 11.8 you have a dead battery. I assume you are measuring the voltage under pump load. What is the voltage of the battery at rest?

    PPS Continuing to run the pump on low voltage is a recipe for burning out the pump fast(er)
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  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    #4
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    Re: What's wrong, help needed....

    that is a very large draw normally at 1100watts and startup power must be tremendous. either suspect the batteries not providing enough power for the startup surge or the inverter may not be handling the startup surge or both. if the inverter is modsine this can further complicate it with wasted power and overheating of the pump motor can't be ruled out although unlikely if it's under water.
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  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    #5
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    Re: What's wrong, help needed....

    quote from icarus,
    "PS If your battery voltage at rest is 11.8 you have a dead battery. I assume you are measuring the voltage under pump load. What is the voltage of the battery at rest?"

    now what i was thinking was that the battery started out at a full charge (thinking positively and the light pun intended) and was drawn down to 11.8v from the heavy loading upon the battery. no matter the case it isn't good.
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  • CBHunter
    CBHunter Solar Expert Posts: 39 ✭
    #6
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    Re: What's wrong, help needed....

    I have not put a voltmeter on the batteries, but my Flexmax80 was giving me a reading of 11.8 volts. ( pump not running )
    The inverter was able to run the pump for several hours ( not continuously ) I'm pretty sure it can handle the surge, because it did many on & off without no problem. I just don't understand why the inverter doesn't shut itself off if the voltage is to low???
    BTW inverter is a Power Bright PW-6000-12, modified sine wave.
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  • PhilS
    PhilS Solar Expert Posts: 370 ✭✭✭
    #7
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    Re: What's wrong, help needed....

    I think the previous members have confirmed your suspicions about the voltage.

    I'll add that I had problems using an MSW inverter and a 1/2hp water pump. After a few years, sometimes the pump would "want to start" but couldn't due to the MSW. That eventually devolved to where the smoke got out of the pump and I had to replace it. Shortly afterward I moved a true sine wave inverter onto that circuit and haven't had a problem since (well over a year now).

    I suspect your pump may be objecting to both the waveform and the voltage.

    Phil
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  • CBHunter
    CBHunter Solar Expert Posts: 39 ✭
    #8
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    Re: What's wrong, help needed....

    Thanks a lot for the tip, I will consider the true sine wave. Too bad I just bought this one! If the voltage is ok, you still think I can damage my pump?
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  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    #9
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    Re: What's wrong, help needed....

    get your battery bank back up to a good charge % and see if it will still act up.
    as to burning out your pump, we can't rule that out because the msw inverter dumps extra harmonic power into inductive loads like motors. this will hold true for your vacuum cleaner too. any and all motor lifespans can be shortened using msw.
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  • icarus
    icarus Solar Expert Posts: 5,436 ✭✭✭✭
    #10
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    Re: What's wrong, help needed....

    If your flex-mate is calling the battery ~11.8 with no load,,, then clearly you battery isn't charged! I would get the batteries up to full charge asap,, either by using the genny,, or reducing the loads until they can come up to proper SG and ~12.7 at rest.

    My hunch is that in spite of your best intentions you have been taking out more from the batteries that you have been putting back in.

    Tony
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  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    #11
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    Re: What's wrong, help needed....

    AC induction motors do not like MSW. It is essentially like hooking it up to low voltage at the best of times. That is, your meter reads 120 VAC but the motor "sees" 95 VAC. Eventually this will burn out the motor.

    It will work sometimes (curiously, the compact motors accept MSW more readily than the larger ones - this gets complicated so let's just leave it, okay? :D ). Problem is, when the pump is trying to start under pressure it takes even more current to get it going. Your inverter current capacity drops off as the batteries go down, so the pump ends up "seeing" very low voltage even though your meter will still read 120 VAC at the inverter. The inverter is probably capable of running until batteries reach 10.5 VDC before shutting down. Furthermore, not all MSW inverters produce the same waveform - some are better than others.

    Pure sine wave is the best way to solve this problem. You should also be looking at your battery bank size and charge array in regards to your over-all power requirements as you really don't want batteries being dragged down too low.

    Or put in a really big pressure tank and charge it with gen power or off the grid.
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  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    #12
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    Re: What's wrong, help needed....

    i should also mention that the built-in shutoff features on some inverters aren't worth a crap as your battery should not be drawn down to dead or 100% dod. even those that spec 11v for the shutoff is way too low.
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  • n3qik
    n3qik Solar Expert Posts: 741 ✭✭
    #13
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    Re: What's wrong, help needed....

    Ok I see the inverter has a meter also. Lets do this, with the pump off. Is the meter on the inverter and Flex-mate reading the same? Now get the pump to turn on, what is the meter on the inverter at ??

    The well, how deep is the pump at. At what pressure is the on/off settings ? Is there a control box for pump?
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  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    #14
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    Re: What's wrong, help needed....

    Reading from your specs: Eight 530 A/hr 6V batteries? On a 12 V system that's 2120 amp hours total. They would want a minimum charge rate of about 100 amps! 4 * 175 W panels would be 700 watts maximum, @ 12 V = no more than 60 amps charge current available. This doesn't include the usual de-rating for inefficiencies.

    I'd say there's no way your panels are able to keep that battery bank charged - which is a different problem, but still a problem. Try disconnecting all but one set of batteries (and charge all the rest) and see if you can't keep the system voltage up above 12.5.

    You spent a lot of money on those Surettes - why did you buy the cheap inverter? :confused:

    Usual caveat: my calculations could be completely wrong. It's happened before and will again! :p
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  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    #15
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    Re: What's wrong, help needed....

    good catch marc as he only has about a 1.85% charge rate. you need to try getting them charged asap even if with an automotive type charger feeding the bulk charge too. when dealing with those chargers be sure to stop them from charging past the normalized voltage maximum for those batteries or risk boiling out the electrolyte and damaging the batteries as they are not regulated like a charge controller is.
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  • mike95490
    mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    #16
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    Re: What's wrong, help needed....
    niel wrote: »
    good catch marc as he only has about a 1.85% charge rate. you need to try getting them charged asap even if with an automotive type charger feeding the bulk charge too. when dealing with those chargers be sure to stop them from charging past the normalized voltage maximum for those batteries or risk boiling out the electrolyte and damaging the batteries as they are not regulated like a charge controller is.

    I'm not sure an automotive charger could "cook" a battery bank of that size.
    Powerfab top of pole PV mount | Listeroid 6/1 w/st5 gen head | XW6048 inverter/chgr | Iota 48V/15A charger | Morningstar 60A MPPT | 48V, 800A NiFe Battery (in series)| 15, Evergreen 205w "12V" PV array on pole | Midnight ePanel | Grundfos 10 SO5-9 with 3 wire Franklin Electric motor (1/2hp 240V 1ph ) on a timer for 3 hr noontime run - Runs off PV ||
    || Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
    || VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A

    solar: http://tinyurl.com/LMR-Solar
    gen: http://tinyurl.com/LMR-Lister ,

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  • CBHunter
    CBHunter Solar Expert Posts: 39 ✭
    #17
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    Re: What's wrong, help needed....
    icarus wrote: »
    If your flex-mate is calling the battery ~11.8 with no load,,, then clearly you battery isn't charged! I would get the batteries up to full charge asap,, either by using the genny,, or reducing the loads until they can come up to proper SG and ~12.7 at rest.

    My hunch is that in spite of your best intentions you have been taking out more from the batteries that you have been putting back in.

    Tony

    This is also what i think, my batteries are charging right now, it is a perfect sunny day here. I will try it with the batteries fully charged.
    Thanks
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  • CBHunter
    CBHunter Solar Expert Posts: 39 ✭
    #18
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    Re: What's wrong, help needed....
    Cariboocoot wrote: »
    Reading from your specs: Eight 530 A/hr 6V batteries? On a 12 V system that's 2120 amp hours total. They would want a minimum charge rate of about 100 amps! 4 * 175 W panels would be 700 watts maximum, @ 12 V = no more than 60 amps charge current available. This doesn't include the usual de-rating for inefficiencies.

    I'd say there's no way your panels are able to keep that battery bank charged - which is a different problem, but still a problem. Try disconnecting all but one set of batteries (and charge all the rest) and see if you can't keep the system voltage up above 12.5.

    You spent a lot of money on those Surettes - why did you buy the cheap inverter? :confused:

    Usual caveat: my calculations could be completely wrong. It's happened before and will again! :p


    I'm planning to add 2 more 175 watts panels to my existing array. I'm also looking for a charger to be kooked up to the genny. Have any recommendations? As for the inverter, I had a real good deal on it, this is why I bought it, I do realize it is not the best.
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  • CBHunter
    CBHunter Solar Expert Posts: 39 ✭
    #19
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    Re: What's wrong, help needed....

    BTW I forgot to mention, right now everything is hooked up temporarely. My panels are sitting in my trailer in my backyard, my batteries, controller and inverter in my garage. I'm running the waterpump of my house to do some tests. When all the snow will be melted, I'm going to do this install in my log cabin ( photo in profile )
    up north. My pump is similar to the one in my house. I just want to make sure everything is OK before I go up there and do the install, it's a five hour drive in the woods!!! I'm going there maybe once a month, so the batteries have some time to recharge, my longest stay should'nt be more than a week. This is still a lot considering a family of four. ( showers, toilet, cooking, etc )
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  • icarus
    icarus Solar Expert Posts: 5,436 ✭✭✭✭
    #20
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    Re: What's wrong, help needed....

    Take advantage of the sun,, but put them on the gennie at the same time,,, get them as full as possible,, as fast as possible to limit a damage.

    T

    PS look at the IOTA or the Xantrex TC series of charges. The TC series are very well suited to charge off a genny efficiently.

    T
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  • BB.
    BB. Super Moderators, Administrators Posts: 33,447 admin
    #21
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    Re: What's wrong, help needed....

    Divide your charging current into the battery capacity...

    If you are near 0% state of charge:

    2120AH/60 amps = 35 hours

    35 hours / 5 hours of "full sun" per day = 7 days to fully charge the battery bank from solar panels alone.

    You really should fire up the generator and hook a good sized battery charger on the bank and get that thing to at least 80%-90% state of charge before using the solar panels to finish off... And, it probably would not hurt to let the generator run a couple extra hours to equalize the bank too.

    Get your self a hydrometer (and accurate thermometer) to measure specific gravity (the "gold standard" to measure flooded cell state of charge) such as (or equivalent):

    wind-sun_2050_3042969Freas HD98C Precision Hydrometer Set

    For longer term... Get your self a battery monitor. The Trimetric is a good low cost unit... The Xantrex linklite / linkpro are good high end systems (I like the programmable alarm contact you can set to turn off/ring a bell if you take your batteries below 50% State of Charge--great if there are others that need to monitor power--spouse, guests, etc.).

    wind-sun_2050_2431644Trimetric TM2020 Battery Monitor System
    Shows state of charge and other information about deep cycle battery sytems

    wind-sun_2045_9146840Xantrex LinkLITE Dual Battery Monitor
    Xantrex dual battery monitor system

    wind-sun_2045_9161581Xantrex LinkPRO Dual Battery Monitor System
    Xantrex dual battery monitor

    There will easily pay for themselves if they save your next set of batteries from deep discharge/deficit charging damage.


    You can review this thread about a trailer solar panel + controller + battery monitor install. Kevin also made a Youtube Video that shows how the whole system was installed and works with a Battery Monitor.

    And "2manytoyz" has a nice page documenting the install and function of a Xantrex LinkPro Battery Monitor.


    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
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  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    #22
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    Re: What's wrong, help needed....
    mike90045 wrote: »
    I'm not sure an automotive charger could "cook" a battery bank of that size.


    i didn't think so either, but i managed to cook my walmart batteries with about a 2% charge rate 4-5hrs a day from solar. if he uses both the pv and battery chargers at the same time this affords a faster and higher charge rate that needs watched. the solar will back off, but the automotive charger would not. the use of regulated charging all of the way will take any guesswork out of the equation in any case. he will not be doing this day after day like i did so an overcharge once will not do much harm. just add some distilled water if that happens. it's still best not to exceed specs though.
    edit to add;
    of course this also depends on how large a charger we are talking about as a little 2 or 6a charger won't do much. he needs a larger charger than this and as big as he can get it even though every little bit helps.
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  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    #23
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    Re: What's wrong, help needed....

    May I just ask why you have such a large battery bank?

    At 50% DOD that bank would supply 12 kW/hrs of power to your 12 V system. That's about five times what I use at my cabin, with water pump. Ordinarily we try to design systems so that they recharge each day, not over a period of days. That bank would require three charge controllers and about 3600 watts of solar panels to charge up daily. Another 350 watt array isn't going to make much difference.

    I suggest you get a handle on your power requirements and see if you can scale back a little. :roll:
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  • CBHunter
    CBHunter Solar Expert Posts: 39 ✭
    #24
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    Re: What's wrong, help needed....
    Cariboocoot wrote: »
    May I just ask why you have such a large battery bank?

    At 50% DOD that bank would supply 12 kW/hrs of power to your 12 V system. That's about five times what I use at my cabin, with water pump. Ordinarily we try to design systems so that they recharge each day, not over a period of days. That bank would require three charge controllers and about 3600 watts of solar panels to charge up daily. Another 350 watt array isn't going to make much difference.

    I suggest you get a handle on your power requirements and see if you can scale back a little. :roll:


    You run a 110vac water pump and other appliances in your cabin? Can you tell me what system do you have ? ( list of equipement )
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  • CBHunter
    CBHunter Solar Expert Posts: 39 ✭
    #25
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    Re: What's wrong, help needed....

    Guys, correct me if I'm wrong, I'm no expert, but since I will be at my cabin only once a month. ( on average ) I tought that my solar panel requirements would be much smaller than usual!?
    My thinking was, that having a large battery bank would allow me to have sufficient power to run my pump. Even if it would take several days to charge them up wasn't a big deal, as long as I have enough power for a week.....
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  • BB.
    BB. Super Moderators, Administrators Posts: 33,447 admin
    #26
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    Re: What's wrong, help needed....

    Well... It can work that way.

    The issues (that I see):
    1. Self discharge of batteries... Goes up as they age--so solar panel has to be sized to make up the losses there. You will have to look around for the specs. on your battery bank, but depending on batteries and age you might get between 2% to 10%+ per month self discharge rate.
    2. Solar panel is not large enough to equalize your battery bank--so you will need to fire up the genset when you need to equalize (~5%-13% rated bank capacity/current).
    3. You don't want to discharge your bank below ~75% capacity. If the batteries spend any significant time below ~75% state of charge--the sulfates on the plates will start to harden (within hours or day) and your battery's capacity will begin to fall.
    4. You have a large bank--so may not be an issue with your setup--but when you pull high loads (or even high charging currents) the "efficiency" of the battery begins to fall... Roughly, C/20 discharge rate and less--very efficient. C/10 and higher discharge rates, more losses as heat (warming battery bank).
    So--if you can meet 1-3, and take care of the issues with #4 with more generator charging time (if needed)--you should be OK.
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
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  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    #27
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    Re: What's wrong, help needed....
    CBHunter wrote: »
    Guys, correct me if I'm wrong, I'm no expert, but since I will be at my cabin only once a month. ( on average ) I tought that my solar panel requirements would be much smaller than usual!?
    My thinking was, that having a large battery bank would allow me to have sufficient power to run my pump. Even if it would take several days to charge them up wasn't a big deal, as long as I have enough power for a week.....

    Not quite. If the panels don't produce enough current in respect to the size of the battery bank, the bank will never charge. It just goes down, down, down. Batteries in need of charge are a resistance load on the panels. It's like trying to charge a car battery with one of those 500 mA wall transformers; it won't work. Instead of the supply bringing the batteries up, the batteries drag the supply down. Then it fries. Don't worry: the solar panels won't fry.

    The battery bank is sized to supply the load requirements in between charge windows. You can size them large enough to handle a spell of bad weather, but that just means you need all the more panels to bring them up once the sun comes out. Generally speaking, the charge rate should be 5%-10% of the A/hr rating of the batteries. Not enough current = not enough "oomph" to shove the electrons around. :D

    My system consists of 4 175 W Sharp panels feeding 48 V nominal into an Outback MX-60 which charges a bank of (inadequately rated Interstate) 320 A/hr batteries. This powers an Outback FX 3024 true sine inverter, which include a generator input/charge feature in case the sun doesn't shine.

    My loads: 240 watts for the 'frige (cycles about 1/3 the time, and hits 500 watts on defrost). Water pump is a 1/3 HP shallow well that charges a very LARGE pressure tank so it doesn't cycle a lot (start up uses more current than run). There is also a 1 HP 'digester pump' for the septic system, which only runs about 1 minute per day. The big user is the computer/satellite/phone set-up which chews a steady 150 watts average when on. There are the usual CFL lights and a small radio/Cd player.

    My 'rules of thumb' for system design:

    Inverter should be sized to handle the maximum load at any given time (in my case the massive draw of the 1 HP pump plus the 'standard' loads).

    The batteries should be able to handle the day's ('over-night', as it were) power usage (mine at 3840 watt/hrs are above usage rating - if they really were as advertised).

    The solar panels should be capable of recharging the batteries as quickly as practical (my batteries recharge in less than 3 hours on a good day - PV array handles all power after that 'til the sun starts to go). Over-all the system produces 2.5 kW/hrs on a good day.

    Things I will improve: not good enough solar exposure for 'marginal' days means I run the gen more than I like. Batteries that really meet spec would be nice - like some Trojan L16H's.
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  • icarus
    icarus Solar Expert Posts: 5,436 ✭✭✭✭
    #28
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    Re: What's wrong, help needed....

    While that is generically correct,,, the error here is that the battery bank is SO large compared to the solar input,,, that the solar can just barely cover the stand by losses of the batteries. I would guess that your system puts out ~50 amps under ideal sun,, some where in the nieghbourhood of 2% of capacity,,, just enough to keep up at float, if that.

    The rule of thumb as I'm sure you know is ~5-13% would be normal.

    My hunch is that by leaving your batteries significantly discharge more than one, you have begun to kill your bank! Batteries left below ~80% for more than a couple of day will begin to sulphate in a hurry. As such they can't take much of a charge anymore, and can't hold one.

    As has been suggested,, I would give them a massive charge asap, keeping the specific gravity of each cell closely monitored until you get them all up to the proper SG.

    Tony
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  • CBHunter
    CBHunter Solar Expert Posts: 39 ✭
    #29
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    Re: What's wrong, help needed....
    Cariboocoot wrote: »
    Not quite. If the panels don't produce enough current in respect to the size of the battery bank, the bank will never charge. It just goes down, down, down. Batteries in need of charge are a resistance load on the panels. It's like trying to charge a car battery with one of those 500 mA wall transformers; it won't work. Instead of the supply bringing the batteries up, the batteries drag the supply down. Then it fries. Don't worry: the solar panels won't fry.

    The battery bank is sized to supply the load requirements in between charge windows. You can size them large enough to handle a spell of bad weather, but that just means you need all the more panels to bring them up once the sun comes out. Generally speaking, the charge rate should be 5%-10% of the A/hr rating of the batteries. Not enough current = not enough "oomph" to shove the electrons around. :D

    My system consists of 4 175 W Sharp panels feeding 48 V nominal into an Outback MX-60 which charges a bank of (inadequately rated Interstate) 320 A/hr batteries. This powers an Outback FX 3024 true sine inverter, which include a generator input/charge feature in case the sun doesn't shine.

    My loads: 240 watts for the 'frige (cycles about 1/3 the time, and hits 500 watts on defrost). Water pump is a 1/3 HP shallow well that charges a very LARGE pressure tank so it doesn't cycle a lot (start up uses more current than run). There is also a 1 HP 'digester pump' for the septic system, which only runs about 1 minute per day. The big user is the computer/satellite/phone set-up which chews a steady 150 watts average when on. There are the usual CFL lights and a small radio/Cd player.

    My 'rules of thumb' for system design:

    Inverter should be sized to handle the maximum load at any given time (in my case the massive draw of the 1 HP pump plus the 'standard' loads).

    The batteries should be able to handle the day's ('over-night', as it were) power usage (mine at 3840 watt/hrs are above usage rating - if they really were as advertised).

    The solar panels should be capable of recharging the batteries as quickly as practical (my batteries recharge in less than 3 hours on a good day - PV array handles all power after that 'til the sun starts to go). Over-all the system produces 2.5 kW/hrs on a good day.

    Things I will improve: not good enough solar exposure for 'marginal' days means I run the gen more than I like. Batteries that really meet spec would be nice - like some Trojan L16H's.




    I'm confused, 4175 watts on a MX-60??? In my owners manual they say that my Flexmax 80 can not handle more than 1250 watts with a 12 volts configuration.....
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  • CBHunter
    CBHunter Solar Expert Posts: 39 ✭
    #30
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    Re: What's wrong, help needed....
    Cariboocoot wrote: »
    Not quite. If the panels don't produce enough current in respect to the size of the battery bank, the bank will never charge. It just goes down, down, down. Batteries in need of charge are a resistance load on the panels. It's like trying to charge a car battery with one of those 500 mA wall transformers; it won't work. Instead of the supply bringing the batteries up, the batteries drag the supply down. Then it fries. Don't worry: the solar panels won't fry.

    The battery bank is sized to supply the load requirements in between charge windows. You can size them large enough to handle a spell of bad weather, but that just means you need all the more panels to bring them up once the sun comes out. Generally speaking, the charge rate should be 5%-10% of the A/hr rating of the batteries. Not enough current = not enough "oomph" to shove the electrons around. :D

    My system consists of 4 175 W Sharp panels feeding 48 V nominal into an Outback MX-60 which charges a bank of (inadequately rated Interstate) 320 A/hr batteries. This powers an Outback FX 3024 true sine inverter, which include a generator input/charge feature in case the sun doesn't shine.

    My loads: 240 watts for the 'frige (cycles about 1/3 the time, and hits 500 watts on defrost). Water pump is a 1/3 HP shallow well that charges a very LARGE pressure tank so it doesn't cycle a lot (start up uses more current than run). There is also a 1 HP 'digester pump' for the septic system, which only runs about 1 minute per day. The big user is the computer/satellite/phone set-up which chews a steady 150 watts average when on. There are the usual CFL lights and a small radio/Cd player.

    My 'rules of thumb' for system design:

    Inverter should be sized to handle the maximum load at any given time (in my case the massive draw of the 1 HP pump plus the 'standard' loads).

    The batteries should be able to handle the day's ('over-night', as it were) power usage (mine at 3840 watt/hrs are above usage rating - if they really were as advertised).

    The solar panels should be capable of recharging the batteries as quickly as practical (my batteries recharge in less than 3 hours on a good day - PV array handles all power after that 'til the sun starts to go). Over-all the system produces 2.5 kW/hrs on a good day.

    Things I will improve: not good enough solar exposure for 'marginal' days means I run the gen more than I like. Batteries that really meet spec would be nice - like some Trojan L16H's.


    Marc, how large is your pressure tank?
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  • BB.
    BB. Super Moderators, Administrators Posts: 33,447 admin
    #31
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    Re: What's wrong, help needed....
    CBHunter wrote: »
    I'm confused, 4175 watts on a MX-60??? In my owners manual they say that my Flexmax 80 can not handle more than 1250 watts with a 12 volts configuration.....

    That "4 175 watt" might be 4x 175 watt panels.

    With production at "2.5 kWhrs" on a good day--that daily kWhr output would be very possible with 4x175=700 watts of solar panels into a DC battery bank.

    -Bil
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
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