High voltage off grid

davidwillisdavidwillis Solar Expert Posts: 104 ✭✭
I am planning on converting my vehicle to be an electric vehicle, however I would also like to use the car for a battery backup for my house, since it will be able to store a lot of power in it (about 40 kwh). However it will be at about 200VDC. I don't see off grid inverters that go over 48v. So my questions are.

1- are there any inverters that will run off 200VDC input

2- if not, is it best to have some dc disconnects to rearrange the batteries to be 48VDC, or use a DC to DC converter to drop the voltage down to 48 volts, then use an inverter.

This would only be used for backup power when the grid is down. I would be able to charge the batteries using the charger in the car, and my solar panels that currently go to my grid tie inverter. But the grid tie inverter won't work with the power out, so I need a second inverter to use as backup power. I only need about a 2kw inverter.

Thanks
David

Comments

  • peakbaggerpeakbagger Solar Expert Posts: 341 ✭✭✭
    Re: High voltage off grid

    There is an individual this forum that uses a industrial UPS which is rated for a high voltage series input from his prius. If you do some searching I expect you will find his rather informative posts.
  • CariboocootCariboocoot Banned Posts: 17,615 ✭✭
    Re: High voltage off grid

    I think this is the thread you want to look at: http://forum.solar-electric.com/showthread.php?12962-Using-a-Prius-as-a-generator
  • techntrektechntrek Solar Expert Posts: 1,372 ✭✭✭
    Re: High voltage off grid

    That would be me. See the link in my signature. APC SURT3000, SURT5000, and SURT6000 use a nominal DC voltage of 192 volts. These require also buying a transformer to get 120/240 split-phase and the SURT003 works well for this. You can get the UPS and transformer for about $250 each if you search carefully. These can be cold/black started from the battery without AC input.

    There is also the Toshiba 1600EP and 1600XP (also found under the Alpha brand name and one other) with nominal voltages of 216 volts. They have built-in transformers which makes them much heavier but you don't have to hunt down a separate transformer. Toshiba groups models with varying specs under the one model number so you must be careful to look at the kVA capacity to get the right ones. The 3.6 and 6 kVA versions have the nominal DC voltage of 216 volts, with an alarm at 192 and shutdown at 170. A downside to the Toshiba line is they can't be cold/black started from the battery - you need AC input first.

    One more option is the AIMS Prius 2kw PSW inverter, which can be found on ebay for just under $400.
    4.5 kw APC UPS powered by a Prius, 12 kw Generac, Honda EU3000is
  • davidwillisdavidwillis Solar Expert Posts: 104 ✭✭
    Re: High voltage off grid

    Thanks, that is perfect. I will have to read over the details, but the first option looks perfect.
  • bill von novakbill von novak Solar Expert Posts: 891 ✭✭✭✭
    Re: High voltage off grid
    1- are there any inverters that will run off 200VDC input

    Here's the one I used for a Prius conversion:

    http://www.ebay.com/itm/AIMS-Prius-2kW-Pure-Sine-Wave-Inverter-for-Backup-Power-Generator-/200841111789

    180-260 volts in, 2kW nominal, 4kW surge.
  • mike95490mike95490 Solar Expert Posts: 8,614 ✭✭✭✭✭
    Re: High voltage off grid
    Here's the one I used for a Prius conversion:
    http://www.ebay.com/itm/AIMS-Prius-2kW-Pure-Sine-Wave-Inverter-for-Backup-Power-Generator-/200841111789
    180-260 volts in, 2kW nominal, 4kW surge.

    Slick, but without a Prius, what would one charge the batteries with ?
    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 ,

  • davidwillisdavidwillis Solar Expert Posts: 104 ✭✭
    Re: High voltage off grid

    I plan on using the emw 12000 watt charger. It will take AC or DC voltage, so I can charge with 110/220, or my DC solar panels. Normally I will just charge with 220VAC, but when the power goes out, I can just plug my panels into the charger. However with 40 KWH, it will last days without even charging. But if the power is out for a few days, and it is cloudy, I could always plug in a portable generator to charge them back up.
  • bill von novakbill von novak Solar Expert Posts: 891 ✭✭✭✭
    Re: High voltage off grid
    mike95490 wrote: »
    Slick, but without a Prius, what would one charge the batteries with ?

    My first choice would be a Manzanita Micro charger (20 amps at 200 volts.) It's a very versatile charger, but it's pricey. However there are a lot of other EV chargers out there that will work.
  • techntrektechntrek Solar Expert Posts: 1,372 ✭✭✭
    Re: High voltage off grid

    Yup, definitely don't want to rely on the built-in chargers in the UPSs, they are designed for much smaller batteries.
    4.5 kw APC UPS powered by a Prius, 12 kw Generac, Honda EU3000is
  • davidwillisdavidwillis Solar Expert Posts: 104 ✭✭
    Re: High voltage off grid

    I couldn't find the APC setup, I think it may be easier to just use the AIMS Prius 2kw PSW inverter.

    BTW, you can get a kit to build an emw 12000, but if you buy it all built, it is about $2300 for the pfc version. It is pricy, but will do 12kw of charging if you can supply that much....
  • mike95490mike95490 Solar Expert Posts: 8,614 ✭✭✭✭✭
    Re: High voltage off grid

    Will any of the EV chargers, run off PV. OR would I need to invert it to 240VAC, then feed that to the charger. Any chargers have a internal HV DC buss that PV could feed directly? (and then collapse the voltage as the charger ramps up past the IV curve....)
    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 ,

  • davidwillisdavidwillis Solar Expert Posts: 104 ✭✭
    Re: High voltage off grid

    I am not sure about all the chargers, but the one I have been looking at will take a DC input.


    Specs

    Input voltages:



    240VAC or 110VAC for the non-PFC version
    90-260VAC for the PFC version (output power automatically limited to ~1.5kW if connected to 110VAC)
    Both non-PFC and PFC units can be used to charge your battery from a DC source. This feature can be used to charge one EV from another, to use the charger with a separate rectifier (e.g., for 3-phase operation), charger your EV from your solar array / stationary battery, etc.
    Non-PFC units can be used with DC input above the voltage of the battery being charged (up to ~400 VDC)
    PFC units can be used with any DC source ~100-400VDC
    Output voltage

    Field - programmable - use simple button-LCD interface to change parameters at ANY time - see our videos below for examples
    ~20-250VDC (non-PFC version)
    ~20-350VDC (PFC version; upgradeable to 450VDC with simple modifications; up to 800V possible with more significant mods)
    Output current:

    Up to 70A continuous
    100A option offered for low-voltage outputs
    Output power:

    12kW rated
    Tested to 15kW in our labs
    Efficiency at full power:



    95%+ for non-PFC version (offset by higher losses in AC wires, however)
    93%+ for PFC version
    Switching frequency:

    22kHz (PFC stage)
    15-20kHz (buck output stage)
    Control methods:

    Manual - charger can be programmed for any input / output current / voltage at any time in field - no need to do any factory setting!
    Automatic:
    J1772 support with automatic power regulation (charger reads and interprets the J1772 pilot signal & limits max power draw to the one suggested by the EVSE)
    NEW [August 2013]: Serial control now available for fully automatic operation. Multiple chargers can be run in parallel, controlled by one simple head unit. Work ongoing on CAN-to-Serial conversion to enable full CAN-driven operation. Let us know if you can help!
    Additional features:

    BMS stop-charge TTL input
    End-of-Charge TTL output
    Hardware current limiting
    Thermal output derating above 55C heatsink temperature
    Inductor temperature sensing
    Flexible battery settings: set your battery type (Li, NiXX are currently available), number of batteries, capacity through a simple-to-use interface
  • davidwillisdavidwillis Solar Expert Posts: 104 ✭✭
    So I have been using the Aims Prius inverter and it has been working great.  However now I have an application where I would like to use something for a 120VDC input.  Does anyone know of anything that will convert 120VCD to 120VAC?

    Thanks
  • MarkCMarkC Solar Expert Posts: 188 ✭✭✭
    So I have been using the Aims Prius inverter and it has been working great.  However now I have an application where I would like to use something for a 120VDC input.  Does anyone know of anything that will convert 120VCD to 120VAC?

    Thanks
    The APC SMX3000RMLV2UNC is a line-interactive UPS that uses nominal 120 volt DC input for the inverter section.  Pricey!
    BTW, do you know of any supplier of a high voltage (DC), mppt charge controller (200+ VDC)?

    3850 watts - 14 - 275SW SolarWorld Panels, 4000 TL-US SMA Sunny Boy Grid tied inverter.  2760 Watts - 8 - 345XL Solar World Panels, 3000 TL-US SMA Sunny Boy GT inverter.   3000 watts SMA/SPS power.  PV "switchable" to MidNite Classic 250ks based charging of Golf cart + spare battery array of 8 - 155 AH 12V Trojans with an  APC SMT3000 - 48 volt DC=>120 Volt AC inverter for emergency off-grid.   Also, "PriUPS" backup generator with APC SURT6000/SURT003  => 192 volt DC/240 volt split phase AC inverter.  
  • davidwillisdavidwillis Solar Expert Posts: 104 ✭✭
    Wow, those are pricey!...

    I plan on using two 60VDC charge controllers, and charge half of the bank with each one.
  • MarkCMarkC Solar Expert Posts: 188 ✭✭✭
    Midnite made a MPPT style 120VDC CC for a short while - I wonder if 2 stacked could charge up to 240 VDC? which, in theory, could charge a Gen 1 and 2 Prius battery directly from solar - with proper charge profiles AND efficient use of PV panels.  Hard to find any of these!  For your application, it might be the answer for the CC side of things.  Can U tell me more about your "battery" set up as I have a partially functioning, but workable SMX3000 (the display is out, but can be controlled by the network card).  I've considered going to it for off-grid as it is very efficient.
    3850 watts - 14 - 275SW SolarWorld Panels, 4000 TL-US SMA Sunny Boy Grid tied inverter.  2760 Watts - 8 - 345XL Solar World Panels, 3000 TL-US SMA Sunny Boy GT inverter.   3000 watts SMA/SPS power.  PV "switchable" to MidNite Classic 250ks based charging of Golf cart + spare battery array of 8 - 155 AH 12V Trojans with an  APC SMT3000 - 48 volt DC=>120 Volt AC inverter for emergency off-grid.   Also, "PriUPS" backup generator with APC SURT6000/SURT003  => 192 volt DC/240 volt split phase AC inverter.  
  • davidwillisdavidwillis Solar Expert Posts: 104 ✭✭
    My battery setup is not very complicated.  I just have 10 batteries in series.  It is more of an experimental thing right now.  But It will just be an emergency backup that I can use to run a 120VAC cooktop stove and a few 120VAC appliances that will run off DC.  The reason for this is that is is very simple (less things to fail), and EMP Proof (I can just have a couple cheap charge controllers safely protected).  It is also more efficient than using an inverter to run AC.  But I was thinking it would be nice to have an inverter to run a few things like a microwave.  But it is not worth the price of the smx3000.

    I will use two of these for the charge controllers:  http://www.ebay.com/itm/141719192969?_trksid=p2057872.m2749.l2649&ssPageName=STRK:MEBIDX:IT

    They are really the only thing that can fail, so I will have some backups of them



  • PhotowhitPhotowhit Solar Expert Posts: 5,108 ✭✭✭✭

    High voltage DC is very dangerous, What type of 40 KWh battery will you have? 40 Kwh lead acid would be in the 2.5 - 4000 lb range. Lithium might bet getting close to 1000 lbs...

    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
  • davidwillisdavidwillis Solar Expert Posts: 104 ✭✭
    No, this is small.... My 40kw was for my electric car (lithium).  This is just going to be 10 small batteries (8 amp hour).  I will also put in a 10 amp fuse, so it will shut down if it is shorted out.  I am not really sure if DC is that more dangerous than AC (both are dangerous).  It will arc more that is for sure though, but a fuse should stop that before it burns too much...?   To bad I can't find a cheap Inverter that will run off 120VDC.

    thanks
    David
  • inetdoginetdog Solar Expert Posts: 3,123 ✭✭✭✭
    Your best bet for an inverter that take that high a  DC voltage would be the one in a commercial UPS.

    The fuse will stop the DC arc as long as the fuse itself has a DC voltage rating that is high enough. The AC rating of a fuse assumes that the arc from the fuse melting will stop when the AC current passes through zero. In some cases the fuse holder cannot withstand a high DC voltage either.
    SMA SB 3000, old BP panels.
  • vtmapsvtmaps Solar Expert Posts: 3,738 ✭✭✭✭
    It will arc more that is for sure though, but a fuse should stop that before it burns too much...?  

    That is wrong.  An arc can be sustained at currents that are well within the ratings of the OCPD (OverCurrentProtectionDevice=fuse or circuit breaker) and of the wire.  A classic example is arcing that occurs in a loose connection.  These types of arcs are called 'series' arcs. 

    You are probably thinking of 'parallel' arc faults, such as (for example) a hot wire being shorted to ground.  The current in these types of faults MAY be exceed and trip the OCPD.  But you can't count on that... the arc may be sustained at low current levels.

    The reason that building codes now require arc fault protection devices is because OCPD do not protect against arc faults.

    --vtMaps
    4 X 235watt Samsung, Midnite ePanel, Outback VFX3524 FM60 & mate, 4 Interstate L16, trimetric, Honda eu2000i
  • inetdoginetdog Solar Expert Posts: 3,123 ✭✭✭✭
    edited October 2015 #23
    deleted
    SMA SB 3000, old BP panels.
  • inetdoginetdog Solar Expert Posts: 3,123 ✭✭✭✭
    edited October 2015 #24
    There is some heated discussion about what voltage is required to sustain a series arc, as opposed to an intermittent sparking contact. (The discussion is at its heaviest when arguing whether AC  Arc Fault Circuit Interrupters (AFCIs) perform any useful function in a US residential setting.)

    The value will as many welders know, be different between DC and AC since the DC arc does not have to re-ignite 120 times per second at the working electrode spacing

    PS: A sparking contact such as vtMaps describes will usually go one of two ways:
    1. Enough metal is removed to open the circuit permanently, hopefully before a fire starts.
    2. The repeated sparking resolves into a steady high resistance metallic connection called a glowing connection This is what most often starts fires and cannot be detected by either overcurrent devices or AFCIs.

    SMA SB 3000, old BP panels.
  • MarkCMarkC Solar Expert Posts: 188 ✭✭✭
    edited October 2015 #25
    My battery setup is not very complicated.  I just have 10 batteries in series.  It is more of an experimental thing right now.  But It will just be an emergency backup that I can use to run a 120VAC cooktop stove and a few 120VAC appliances that will run off DC.  The reason for this is that is is very simple (less things to fail), and EMP Proof (I can just have a couple cheap charge controllers safely protected).  It is also more efficient than using an inverter to run AC.  But I was thinking it would be nice to have an inverter to run a few things like a microwave.  But it is not worth the price of the smx3000.

    Have you looked into the 48 volt based APC UPSs?  FLA or AGM batteries are easily configured and a wide option of AH availability at the lowest of initial costs.  One cheap PWM CC might suffice for your "experiments".  I actually have several UPSs available in 750 to 5000 VA ranges - all at 48 volt DC.  I know that they are not the most efficient, but low cost and extremely reliable.  Plus with a network card, you can log all "experimental" data that you want.  I've had great experience with this set up to run two ceiling fans, a mid sized refrigerator, big screen TV and sound system, plus a few lights for 10-12 hours off my golf cart deep cycle batteries (2 sets).  I've thought about using the 10 series set up with a SMX3000 UPS because it is so efficient, but worried about that many FLA's in series - plus the high DC voltage involved.


    3850 watts - 14 - 275SW SolarWorld Panels, 4000 TL-US SMA Sunny Boy Grid tied inverter.  2760 Watts - 8 - 345XL Solar World Panels, 3000 TL-US SMA Sunny Boy GT inverter.   3000 watts SMA/SPS power.  PV "switchable" to MidNite Classic 250ks based charging of Golf cart + spare battery array of 8 - 155 AH 12V Trojans with an  APC SMT3000 - 48 volt DC=>120 Volt AC inverter for emergency off-grid.   Also, "PriUPS" backup generator with APC SURT6000/SURT003  => 192 volt DC/240 volt split phase AC inverter.  
  • davidwillisdavidwillis Solar Expert Posts: 104 ✭✭
    48V could be done, but since I will have 10 batteries, it would be easier to have a 60V input, and use half the bank.  Do you know of any that will work of a 60V input?


    MarkC said:
    My battery setup is not very complicated.  I just have 10 batteries in series.  It is more of an experimental thing right now.  But It will just be an emergency backup that I can use to run a 120VAC cooktop stove and a few 120VAC appliances that will run off DC.  The reason for this is that is is very simple (less things to fail), and EMP Proof (I can just have a couple cheap charge controllers safely protected).  It is also more efficient than using an inverter to run AC.  But I was thinking it would be nice to have an inverter to run a few things like a microwave.  But it is not worth the price of the smx3000.

    Have you looked into the 48 volt based APC UPSs?  FLA or AGM batteries are easily configured and a wide option of AH availability at the lowest of initial costs.  One cheap PWM CC might suffice for your "experiments".  I actually have several UPSs available in 750 to 5000 VA ranges - all at 48 volt DC.  I know that they are not the most efficient, but low cost and extremely reliable.  Plus with a network card, you can log all "experimental" data that you want.  I've had great experience with this set up to run two ceiling fans, a mid sized refrigerator, big screen TV and sound system, plus a few lights for 10-12 hours off my golf cart deep cycle batteries (2 sets).  I've thought about using the 10 series set up with a SMX3000 UPS because it is so efficient, but worried about that many FLA's in series - plus the high DC voltage involved.



  • MarkCMarkC Solar Expert Posts: 188 ✭✭✭
    edited October 2015 #27
    Most of the 1500 VA and above APC UPSs use 48V DC in the SU, SUA and SMX lines.  The SMX3000 and the SURT lines use higher voltages (120 and 196 respectively).  Can you parallel/series 8 of them for 48 volts - keep 2 available as spares?  Just remember the internal battery chargers only work consistently with the original specified batteries for these units.  You will have to ignore the battery charge LEDs and turn off the warning beeps!
    3850 watts - 14 - 275SW SolarWorld Panels, 4000 TL-US SMA Sunny Boy Grid tied inverter.  2760 Watts - 8 - 345XL Solar World Panels, 3000 TL-US SMA Sunny Boy GT inverter.   3000 watts SMA/SPS power.  PV "switchable" to MidNite Classic 250ks based charging of Golf cart + spare battery array of 8 - 155 AH 12V Trojans with an  APC SMT3000 - 48 volt DC=>120 Volt AC inverter for emergency off-grid.   Also, "PriUPS" backup generator with APC SURT6000/SURT003  => 192 volt DC/240 volt split phase AC inverter.  
  • bill von novakbill von novak Solar Expert Posts: 891 ✭✭✭✭
    48V could be done, but since I will have 10 batteries, it would be easier to have a 60V input, and use half the bank.  Do you know of any that will work of a 60V input?



    The Outback 48V FX line will work up to 68 volts but you'd have to disconnect the inverter and use a separate charger to charge the batteries fully.  The onboard charger will only take a 60 volt pack to about 2.25 volts per cell which isn't enough for absorb,
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