Wiring the 5K generator to my inverter AC INPUT.

Hairfarm
Hairfarm Solar Expert Posts: 225 ✭✭✭
I created a new thread because it has to do with a generator to inverter question and not an inverter to sub-panel question.
How do you plan to use your Generator Output ?? Is it all going to the Inverter Input and through the transfer switch ??

As a matter of fact, yes, I am wiring my generator output into my inverter directly. It is an inverter / charger @ 2000 watts. But I could use some advice on the best way to accomplish that. Obviously I could just wire a three prong plug to the inverter AC INPUT. Then plug it into the generator manually, but I don't want to do it that way. I'd rather have the generator already started and warmed up before I open the power into the inverter (to either power my AC load panel or charge my batteries, or both at the same time).

Questions:
Since my inverter charges as well as passes generator (AC) power through the inverter to the load panel then I don't think I need a transfer switch right? The "transfer" is happening automatically in the inverter.

All I really need is a convenient way to flip a switch and have the (already running and warmed up) generator immediately start feeding AC power into the inverter. Seems like a much better way to provide power to my inverter than to start up the gen while plugged into my inverter. Seems like "bad" AC power to me.

I was thinking of installing a 20amp breaker with 12awg wire between the generator and the inverter then using the 20 amp breaker as the off/on switch. My generator is a 5k MSW model.

That should work, right?

Comments

  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Wiring the 5K generator to my inverter AC INPUT.

    Is this a 120 VAC only or a 120/240 VAC system?

    But--As you have stated, all seems OK.

    You will have to confirm where the Neutral/Ground bond is made (there may be one inside the genset-->3.5 kW is likely). And one in the AC inverter (although, the inverter could switch the neutral/ground bond with its internal transfer switch).

    Lastly, using the Breaker as a switch. They are not really intended for lots of use as a switch. Breakers can fail over time (have a spare). And I have seen old panels where the breakers rock quite a bit when switched/reset, and I would worry that the panel/bus bar blades/wiring is not really up to constant flexing.

    Does your Inverter/Charger have a generator delay built in? Some of the external (cheap) transfer switches to have a 6-30 second delay circuit built in.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • Hairfarm
    Hairfarm Solar Expert Posts: 225 ✭✭✭
    Re: Wiring the 5K generator to my inverter AC INPUT.
    BB. wrote: »
    Is this a 120 VAC only or a 120/240 VAC system?

    But--As you have stated, all seems OK.

    You will have to confirm where the Neutral/Ground bond is made (there may be one inside the genset-->3.5 kW is likely). And one in the AC inverter (although, the inverter could switch the neutral/ground bond with its internal transfer switch).

    Lastly, using the Breaker as a switch. They are not really intended for lots of use as a switch. Breakers can fail over time (have a spare). And I have seen old panels where the breakers rock quite a bit when switched/reset, and I would worry that the panel/bus bar blades/wiring is not really up to constant flexing.

    Does your Inverter/Charger have a generator delay built in? Some of the external (cheap) transfer switches to have a 6-30 second delay circuit built in.

    -Bill



    Good point about the breaker used as a switch BB. It's a 120VAC system.

    The neutral/ground bond will be made at the panel.

    (Please see text from previous post from me):
    My generator won't be grounded. It will only be rolled out of the shed and used when needed and won't be "living" near any ground source to use effectively. Xantrex tech says ungrounded generators are ok to use, even MSW ones. The default, factory position of the inverter bonding screw is "Auto bonding to ground in invert mode". However, my "shore-power" (actually my generator) will not be grounded. Therefore, I'll have to manually relocate the inverter "bonding" screw in the other hole, the permanently "unbonded in all modes" position. But then I will definitely have to bond the neutral to ground in my AC load panel. That way, I can hook up my non-grounded generator and be set up correctly. The "Auto bonding to ground in invert mode" setting assumes that the shore power (usually for prosine inverter applications like RV's, Boats, etc) will always be grounded. But in my situation my "shore-power" won't be grounded, so I use the "unbonded in all modes" setting and bond at the panel to "force the issue". This is how it was explained to me by Xantrex.



    I'm not sure if the inverter has a delay built-in or not. I'll check the documentation, but I don't recall ever seeing that feature mentioned.

    But I could still keep the breaker in line and use different kind of cutoff switch then right? What type of switch would that be? Something like this maybe:
    http://www.midlandhardware.com/30A-Light-Duty-Safety-Switch-1-Plug-Fuse-Fusible-2-Wire-120240V_p_99981.html


    thanks,
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Wiring the 5K generator to my inverter AC INPUT.

    I think you have it nailed. Grounding that way should be fine (assuming genset does not bond neutral/ground itself).

    You should verify that the genset is does not have a Neutral/Ground bond internally. At 5kW I would worry that it comes "pre-ground bonded" from the factory. Having the Neutral/Green Wire bonded will not "hurt/break" anything. However, in the best case it will cause current to be shared between the White and Green wires (ground should never carry current intentionally--it is there for safety). And, the worst could be if you have GFI breakers/outlets on the genset where you connect, it would pop the GFI protection.

    The disconnect has an internal fuse(s) in it... If you can find a cheaper box without fuses, I would do that. Less to debug when something goes wrong--But will not hurt anything (just use a large enough fuse so that it will never blow and use the breaker for over current protection and always have a spare fuse if you are in the middle of nowhere and/or want redundancy of spares).

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • Hairfarm
    Hairfarm Solar Expert Posts: 225 ✭✭✭
    Re: Wiring the 5K generator to my inverter AC INPUT.

    I could probably use a powerstrip too couldn't I? I could wire up an AC 3-prong outlet to the inverter AC INPUT, then plug a power strip into it. Then just plug the surge protected, 3-prong power strip into the generator. Then after the generator is up and running all I would have to do is turn on the power strip right? Or would that not be robust enough? My generator would only put out 20 amps @ 120VAC max.

    I'm wondering how others with my setup connect their generator when there's no call for a transfer switch. In other words those who only hook up their generators to their inverters occasionally for equalization, etc.



    thanks,
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Wiring the 5K generator to my inverter AC INPUT.

    Power strips and other "light duty" switches work fine in homes because they are almost always operated at a small fraction of their rated current/power.

    When operating a genset against a good sized battery charger (and a depleted battery bank), we are now looking at lots of current for several hours straight--A 15 amp power strip switch running at 80% of 15 amps is 12 amp max continuous for a 15 amp circuit.

    Are you looking at running 20 amps into a load (like the inverter/charger when charging)?

    Where the circuit should be 20 amps / 0.80 NEC derating = 25 amp breaker+wiring rating

    Or where the 20 amp circuit * 80% derating = 16 amps max continuous?

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • Hairfarm
    Hairfarm Solar Expert Posts: 225 ✭✭✭
    Re: Wiring the 5K generator to my inverter AC INPUT.
    BB. wrote: »
    Power strips and other "light duty" switches work fine in homes because they are almost always operated at a small fraction of their rated current/power.

    When operating a genset against a good sized battery charger (and a depleted battery bank), we are now looking at lots of current for several hours straight--A 15 amp power strip switch running at 80% of 15 amps is 12 amp max continuous for a 15 amp circuit.

    Are you looking at running 20 amps into a load (like the inverter/charger when charging)?

    Where the circuit should be 20 amps / 0.80 NEC derating = 25 amp breaker+wiring rating

    Or where the 20 amp circuit * 80% derating = 16 amps max continuous?

    -Bill
    Are you looking at running 20 amps into a load (like the inverter/charger when charging)?
    I just want to be able to charge the batts in addition to providing for the AC loads.

    You know, my 5k generator does have a 30amp 120VAC socket I could use. But then would that overload my AC load panel on the inverting side? All I have in the panel are six 15amp breakers for my circuits.

    2000W (inverter size) / 120VAC = 16.7amp. If I used the 30 amp socket on the gen would the inverter limit the incoming 30amps to 16.7amps on the AC side, but then allow more charging amps on the DC side than the 20amp socket would?

    When operating a genset against a good sized battery charger (and a depleted battery bank), we are now looking at lots of current for several hours straight--A 15 amp power strip switch running at 80% of 15 amps is 12 amp max continuous for a 15 amp circuit.

    But won't those 120VAC amps be converted to DC amps @ 12volt?


    Sorry if this sounds confusing.
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Wiring the 5K generator to my inverter AC INPUT.
    Hairfarm wrote: »
    I just want to be able to charge the batts in addition to providing for the AC loads.

    You know, my 5k generator does have a 30amp 120VAC socket I could use. But then would that overload my AC load panel on the inverting side? All I have in the panel are six 15amp breakers for my circuits.

    2000W (inverter size) / 120VAC = 16.7amp. If I used the 30 amp socket on the gen would the inverter limit the incoming 30amps to 16.7amps on the AC side, but then allow more charging amps on the DC side than the 20amp socket would?

    There should be a maximum input branch circuit rating for your inverter... I could see (note that 1/0.80 = 1.25 -- Same thing):

    2,000 watts * 1/109 VAC minimum * 1.25 NEC derating = 23 amps minimum branch circuit

    Or, a 25 amp minimum breaker/fuse/wiring on the input to the inverter. So, 30 amps, not a big step up.

    Note--The size of the source (amps) does not affect the loads in normal operation. Your pole transformer outside your average North American home is capable of 10,000 amps into a dead short. Yet all your AC loads work just fine.

    The fuse/breaker/wire size is setup to ensure that if the load (or shorted wiring) does draw too much current to be safe for your XX AWG wiring, then the breaker/fuse will trip.

    So, in your case, I would would suggest the 30 amp breaker with somewhere between 12 awg and 8 awg wire would be appropriate for your application (note per NEC, 10 AWG wire is the minimum code allows for a 30 amp branch circuit).

    Wire Current
    Ampacities NEC Table 310-16

    But won't those 120VAC amps be converted to DC amps @ 12volt?

    More or less, remember we work with "Power" in Watts which is Volts * Amps...

    So, from a first estimate, 15 amps * 120 VAC = 1,800 Watts = 12 VDC * 150 Amps

    So, a drop from 120 VAC to 12 VDC gives you 10x the current... Same power, just a "conversion" of voltage and current.

    Note, in real life, the numbers are a bit different... Take that 1,800 Watts and 150 Amps at 12 volts... A "typical" charge controller may actually need:

    150 amps * 14.5 volts charging * 1/0.80 charger efficiency * 1/0.67 charger Power Factor * 1/110 VAC * 1.25 NEC derating = 46 amp circuit

    You need to look the inverter manual in detail. Some can run the charger and the inverter at the same time (generator support) and limit the input current too (i.e., if your input is 20 amps, and you have an 15 amp AC load, it will limit the AC charger to 5 amp AC input current to make sure that inverter/charger does not draw more than 20 amps total on the AC input).
    Sorry if this sounds confusing.

    It is--And we can add Power Factor and Watts vs VA (volt amp) into the mix too (watts is the "power", VA is the actual amperage moving through the wires and is different from Watts by 1/PF)... And the installation manual is the place to get the "exact" information needed (hopefully).

    Do you have a link to the manual for your exact model you can post here?

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • Blackcherry04
    Blackcherry04 Solar Expert Posts: 2,490 ✭✭✭
    Re: Wiring the 5K generator to my inverter AC INPUT.

    I don't see a issue at all using the 30A plug on your generator based on the amp capability of your Inverter transfer switch. The breakers in your box have nothing to do with the transfer current. Even if you had 300 amps of breakers, your only going to be able to consume the 30 amp capability of your generator and 20 amps will go to the charger when you are in Bulk, that means you'll only have 10 amps for loads without cutting into the charger with power share.

    To operate the PROsine at the full 100A charging current rating
    Xantrex recommends a 2kW generator or larger and a breaker size setting of 20A.

    AC Input: The circuit breaker or fuse used to protect the PROsine must be
    rated no more than 30A and must be approved for use on 120Vac branch
    circuits. The wire used between the breaker and the PROsine input must be
    sized to match the circuit breaker, in accordance with the electrical codes or
    regulations applicable to your installation. The “AC Service Rating” setting of
    the PROsine must also be set to match the size of the breaker provided.
  • ChrisOlson
    ChrisOlson Banned Posts: 1,807 ✭✭
    Re: Wiring the 5K generator to my inverter AC INPUT.
    Hairfarm wrote: »
    All I really need is a convenient way to flip a switch and have the (already running and warmed up) generator immediately start feeding AC power into the inverter. Seems like a much better way to provide power to my inverter than to start up the gen while plugged into my inverter. Seems like "bad" AC power to me.

    Frankly, I think you might be making it more complicated than it has to be. Sure, it's nice to have a service panel for your gen with a breaker in it. But for a simple system like this just feeding an inverter that's not necessary because the generator already has a breaker on it. If you want the power off when you start it, just turn that breaker off.

    Secondly, the inverter is not going to use "bad" AC power. They typically will spend a few seconds "qualifying" the AC input to make sure its within spec before it closes its internal transfer relay and passes the power thru to loads (or to its internal charger).
    --
    Chris
  • vtmaps
    vtmaps Solar Expert Posts: 3,741 ✭✭✭✭
    Re: Wiring the 5K generator to my inverter AC INPUT.

    Hairfarm,
    as mentioned by others in this thread you do not need to worry about "bad" AC.... your inverter/charger will not use bad AC.

    Rather than spending time and money on a generator switch, consider putting a Bypass switch on your inverter. A bypass switch lets you bypass the inverter and it switches the generator directly to your service panel. If you ever need to repair or service the inverter its nice to be able to flick a switch and take it out of the circuit. The Midnite bypass switch is two breakers ganged together with a metal plate. One breaker is upside down and the metal plate makes sure that when one is on the other is off. It makes sure that one connection is broken before the other is made so that you don't momentarily connect your inverter and generator outputs together. Look at Midnite's e-panel wiring diagram to see how a bypass switch is connected.

    --vtMaps
    4 X 235watt Samsung, Midnite ePanel, Outback VFX3524 FM60 & mate, 4 Interstate L16, trimetric, Honda eu2000i
  • Blackcherry04
    Blackcherry04 Solar Expert Posts: 2,490 ✭✭✭
    Re: Wiring the 5K generator to my inverter AC INPUT.

    When I do a setup like this I usually use a combination of Male and Female NEMA L-5-30 amp twist lock plugs. You have to make a custom cord from the generator anyway. Put a male and female pigtail on the Inverter and you can unplug it and bypass it, then you can plug the Generator directly into you sub panel if you have a Inverter problem.


    Here is a vendor that has the Plugs and Connectors at a reasonable price. Most Generators use L-5-30 , check yours.

    Male
    http://www.ebay.com/itm/NEMA-L5-30-30-Amp-125V-2-Pole-3-Wire-Grounding-Plug-External-Cord-Grip-/120830426104?pt=LH_DefaultDomain_0&hash=item1c220dfbf8

    Female
    http://www.ebay.com/itm/NEMA-L5-30-30A-125V-2P-3W-Grounding-Female-Connector-/110982867318?pt=LH_DefaultDomain_0&hash=item19d7182976
  • Hairfarm
    Hairfarm Solar Expert Posts: 225 ✭✭✭
    Re: Wiring the 5K generator to my inverter AC INPUT.

    Ok. The problem is there're just too many good ideas on this thread!:D
    ChrisOlson
    Frankly, I think you might be making it more complicated than it has to be. Sure, it's nice to have a service panel for your gen with a breaker in it. But for a simple system like this just feeding an inverter that's not necessary because the generator already has a breaker on it. If you want the power off when you start it, just turn that breaker off.
    There is 30amp breaker on my generator, But it's a push-to-reset type and I don't think I can manually turn it off. I think it has to trip first. My generator manual states that I need to start the gen with nothing plugged into it, then when it stabilizes I can go ahead and plug a cord into it. I'd rather just start it then plug it in (knowing that it's disconnected by a switch/breaker/etc) walk to the utility room and flip the generator power on to the inverter and not have stand there and wait for the generator to warm up / stabilize. That's pretty much my goal. Suggestions?

    Hairfarm - But won't those 120VAC amps be converted to DC amps @ 12volt?

    BB - More or less, remember we work with "Power" in Watts which is Volts * Amps...

    So, from a first estimate, 15 amps * 120 VAC = 1,800 Watts = 12 VDC * 150 Amps

    So, a drop from 120 VAC to 12 VDC gives you 10x the current... Same power, just a "conversion" of voltage and current.

    Note, in real life, the numbers are a bit different... Take that 1,800 Watts and 150 Amps at 12 volts... A "typical" charge controller may actually need:

    150 amps * 14.5 volts charging * 1/0.80 charger efficiency * 1/0.67 charger Power Factor * 1/110 VAC * 1.25 NEC derating = 46 amp circuit

    You need to look the inverter manual in detail. Some can run the charger and the inverter at the same time (generator support) and limit the input current too (i.e., if your input is 20 amps, and you have an 15 amp AC load, it will limit the AC charger to 5 amp AC input current to make sure that inverter/charger does not draw more than 20 amps total on the AC input).

    Prosine Manual:
    Operating Limits for Inverter Operation Power Output


    120Vac; surge to 4.5kW.

    Electrical Specifications: Charge Mode

    AC Input:
    Operating voltage range 90–135Vac
    Nominal current 15Aac at 100A(DC) charge, 120Vac in
    Power factor (100A(DC) charge, 120Vac in) ≥0.98 on sine input
    Nominal frequency 60Hz

    DC Output:
    Nominal voltage 12.0Vdc
    Min battery voltage for charging 0.0Vdc
    Max output voltage 17.5Vdc
    Nominal output current 100A(DC) @ ≤15.0Vdc
    Equalize mode max current ≥10A @ ≤17.5Vdc

    Blackcherry04

    Re: Wiring the 5K generator to my inverter AC INPUT.
    When I do a setup like this I usually use a combination of Male and Female NEMA L-5-30 amp twist lock plugs. You have to make a custom cord from the generator anyway. Put a male and female pigtail on the Inverter and you can unplug it and bypass it, then you can plug the Generator directly into you sub panel if you have a Inverter problem.


    Here is a vendor that has the Plugs and Connectors at a reasonable price. Most Generators use L-5-30 , check yours.

    Male
    http://www.ebay.com/itm/NEMA-L5-30-3...item1c220dfbf8

    Female
    http://www.ebay.com/itm/NEMA-L5-30-3...item19d7182976

    Ok, this sounded like great solution to me until I remembered my inverter AC IN/OUT wiring was 12awg not 10awg like I thought, so I won't be able to use the 30 amp socket on the generator will I?

    Because:
    14 gauge = 15 amp
    12 gauge = 20 amp
    10 gauge = 30 amp

    See image
    Attachment not found.

    I can still use the 20amp/120VAC socket from the generator though. And can still use standard three prong plugs though I think. I know my drawing is not the pigtail method but I'm not understanding what pigtail gets wired to where.

    Can you please clarify?:confused:
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: Wiring the 5K generator to my inverter AC INPUT.

    Current is not dependent on supply but rather load. The gen's output may be capable of 30 Amps, but if it is only loaded to 20 Amps that is all the current that will flow. I'm not sure what sort of programming limits for current are available on the Prosine. If it were an Outback (or many other inverters) you can set an AC IN current limit as well as the charging Amps limit.

    If you need the full 30 Amps then you need to run the larger wire size.
  • Hairfarm
    Hairfarm Solar Expert Posts: 225 ✭✭✭
    Re: Wiring the 5K generator to my inverter AC INPUT.

    Cariboocoot,

    You're right, obviously. My cabin has 14/2 awg romex anyway. So for the AC OUT, the inverters pre-hardwired 12AWG will be fine as it's slight overkill. But originally I just wanted more amps (30) flowing to the AC IN side of the inverter to help with AC loads AND battery charging, simultaneously. But because of the 12awg pre-hardwired in the inverter's INS/OUTS I'll just use the 20amp AC socket on my generator instead of the 30amp. If I have a load that actually needs a 30 amp power source, I'll just plug the load straight into the gen with a L-5-30 plug.

    ...And as far as the generator cut off switch is concerned, I think I can simply use this for the generator on/off switch:
    http://www.homedepot.com/p/Cooper-Wiring-Devices-20-Amp-Single-Pole-Light-Switch-Light-Almond-CS120LA-SP-L/203492553#.UVTiuhnqLrc
    Rated for 20amps, not 15. Cheap and easy. Done Deal;)

    That sound about right? Waay overthinking stuff get exhausting at times *sigh*
  • Blackcherry04
    Blackcherry04 Solar Expert Posts: 2,490 ✭✭✭
    Re: Wiring the 5K generator to my inverter AC INPUT.

    I am having a hard time seeing everything your talking about. The 14/3 is in your cabin branch circuits with their own breakers in your box, I think you said they were 15 amp breakers. That has nothing to do with the amount of amps sent to the buss. If you had 4 breakers you could feed them 60 amps, it would make no difference.

    Your INVERTER is made to be on a 30 Amp input circuit . The Instructions tell you so. It tells you to use # 10 awg wire. Your charger will use 20 amps. They may have # 12 inside the inverter, it meets their code, again it's not your problem.

    ""AC Input Connections
    Figure 3-4 is a cutaway top view of the PROsine wiring compartment. It shows
    one incoming AC cable and its connections to the PROsine wires.
    To make the AC input connections:

    1. Run 10 AWG 2-conductor-plus-ground cable through one of the cable clamps
    on the AC end.""
  • Hairfarm
    Hairfarm Solar Expert Posts: 225 ✭✭✭
    Re: Wiring the 5K generator to my inverter AC INPUT.
    Your INVERTER is made to be on a 30 Amp input circuit . The Instructions tell you so. It tells you to use # 10 awg wire. Your charger will use 20 amps. They may have # 12 inside the inverter, it meets their code, again it's not your problem.


    And on page 3-5 it also states: "To operate the PROsine at the full 100A charging current rating
    Xantrex recommends a 2kW generator or larger and a breaker size setting of 20A."


    So which is it Xantrex?!

    And on page 3-6 it states:

    Table 3-1 Required AC Wire Size vs Breaker Rating
    Breaker Size / wire size
    10A/14AWG
    15A/14AWG
    20A/12AWG
    30A/10AWG

    This is the kind of stuff that that really confuses a newbie like myself. They even state that a 12AWG wire (that they use in their own inverter) is rated for 20A. But then tell you to wire a 30A breaker and the necessary 10AWG wire for it to a 12 AWG wire for both inputs. huh?

    In any case Blackcherry04, can you please provide any clarification about your pigtail system for my gen to inverter connection. It sound perfect for my needs.

    thanks,
  • Blackcherry04
    Blackcherry04 Solar Expert Posts: 2,490 ✭✭✭
    Re: Wiring the 5K generator to my inverter AC INPUT.

    Hairfarm, If you already understand this disregard it. A Inverter / Charger only does one function at a time. It Inverts when there is no AC present. When their is AC present it reverses it's Function and becomes a charger.

    When you give it AC power from your generator it will qualify it and if it's within specifications a transfer relay is activated it takes the Incoming AC and sends it to the AC output of the inverter. At the same time the Inverter reverses it's flow and becomes a charger. To produce 100 amps DC for your batteries takes 20 amps from the generator, that means you only have 10 amps left to go to your loads. You can cut the charger back, but you will waste a lot of fuel doing nothing.

    When you cut the incoming AC power Generator, the Transfer Relay will activate and the charger stops and it reverses and it starts in Invert again off the DC power from your batteries.
  • Blackcherry04
    Blackcherry04 Solar Expert Posts: 2,490 ✭✭✭
    Re: Wiring the 5K generator to my inverter AC INPUT.
    Hairfarm wrote: »
    And on page 3-5 it also states: "To operate the PROsine at the full 100A charging current rating
    Xantrex recommends a 2kW generator or larger and a breaker size setting of 20A."


    So which is it Xantrex?!

    And on page 3-6 it states:

    Table 3-1 Required AC Wire Size vs Breaker Rating
    Breaker Size / wire size
    10A/14AWG
    15A/14AWG
    20A/12AWG
    30A/10AWG

    This is the kind of stuff that that really confuses a newbie like myself. They even state that a 12AWG wire (that they use in their own inverter) is rated for 20A. But then tell you to wire a 30A breaker and the necessary 10AWG wire for it to a 12 AWG wire for both inputs. huh?

    In any case Blackcherry04, can you please provide any clarification about your pigtail system for my gen to inverter connection. It sound perfect for my needs.

    thanks,
    It can be confusing. The 20 amps is what the Charger uses at it's max 100 amp output and that alone requires # 12 awg wire.

    I don't know what to say on the plugs. They have to be wired and the polarity kept correct. It you don't keep it right, be prepared for SMOKE!!!!


    1) Gen cord 1male in & 1 female out
    2) Inverter 1 male in & 1 female out
    3) Input to sub panel 1 male in

    So you'll need 3 male Plugs and 2 female connectors. You'll have to figure out how much power cord you need of 10 / 3 SOW or something like it. I usually put a foot or so on the Inverter Input and Output.

    Every Inverter I install on my customer boats or from the factory are all set up on plugs, so it a inverter goes out, all you do is plug around it and move on. Most larger Inverters are on Range plugs. You have to remember everything that is on the Inverter is always going through it, you lose it your dead in the water on most of your 120V stuff. Even if you lose the DC side your out of business. So the plugs have worked out good.
    .
  • Hairfarm
    Hairfarm Solar Expert Posts: 225 ✭✭✭
    Re: Wiring the 5K generator to my inverter AC INPUT.
    It can be confusing. The 20 amps is what the Charger uses at it's max 100 amp output and that alone requires # 12 awg wire.

    I don't know what to say on the plugs. They have to be wired and the polarity kept correct. It you don't keep it right, be prepared for SMOKE!!!!


    1) Gen cord 1male in & 1 female out
    2) Inverter 1 male in & 1 female out
    3) Input to sub panel 1 male in

    So you'll need 3 male Plugs and 2 female connectors. You'll have to figure out how much power cord you need of 10 / 3 SOW or something like it. I usually put a foot or so on the Inverter Input and Output.

    Blackcherry04,

    Your input, as well as others here, have been incredibly helpful. Thanks so much for the idea of plugs. That is perfectly suited to my application.
    Cariboocoot: Current is not dependent on supply but rather load. The gen's output may be capable of 30 Amps, but if it is only loaded to 20 Amps that is all the current that will flow. I'm not sure what sort of programming limits for current are available on the Prosine. If it were an Outback (or many other inverters) you can set an AC IN current limit as well as the charging Amps limit.

    Not too sure about the current limiting programing feature, but here're the inputs available on my inverter:

    Attachment not found.Attachment not found.

    Every time I think I'm nearing the finish line another "minor" detail blindsides me.:grr

    thanks guys,
  • Blackcherry04
    Blackcherry04 Solar Expert Posts: 2,490 ✭✭✭
    Re: Wiring the 5K generator to my inverter AC INPUT.
    Hairfarm wrote: »

    Not too sure about the current limiting programing feature, but here're the inputs available on my inverter:

    Every time I think I'm nearing the finish line another "minor" detail blindsides me.:grr

    thanks guys,
    What Coot is talking about is " Limiting the Current " by limiting the amount of current ( amps ) used by the charger. Your inverter can do that with the remote, but that does not limit the current that the Transfer Relay will carry forward to your sub panel. That current is being bypassed through the inverter. If your generator puts out 30 amps and you only want 10 amps to go to the charging you can " Limit " the amount going to the charger. Lets say that the generator can give you 30 amps and you want 20 amps for the loads in your cabin, you can " Limit " the charger to 10 amps. It's a way to balance the system. There is no reason to use small wire when you have 30 amps from the generator your paying for anyway, but remember, when you cut the charger back, you'll have less charging of the batteries. Thats ok, that's how we all do it, it's called Power Management. Sometimes you want to cook dinner and heat hot water, so you cut the charger back or off for a while and then turn it back up when your finished. The concept is to use as much of the power as you can.
    .
  • mike95490
    mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    Re: Wiring the 5K generator to my inverter AC INPUT.
    My generator manual states that I need to start the gen with nothing plugged into it, then when it stabilizes I can go ahead and plug a cord into it. I'd rather just start it then plug it in (knowing that it's disconnected by a switch/breaker/etc) walk to the utility room and flip the generator power on to the inverter and not have stand there and wait for the generator to warm up / stabilize. That's pretty much my goal. Suggestions?

    Beware ! Many generators "self energize" from residual magnetic fields in the core. If you leave a load connected when the motor spins down, you can erase that magnetism. Then you need to "Flash" the core.

    And when starting the motor, the power coming out of the generator is way off frequency, it loads the motor down - maybe preventing it from starting properly. (like starting your car with the trans in 3rd gear)

    The hard wired off-grid inverter/chargers solve this, by "qualifying" the generator for 30 sec or so, AFTER they meet the voltage/freq spec, and if they don't have a cool-down mode (to allow the cooling system to cool the motor and alternator down) for a couple minutes, they disconnect when the freq shifts out of spec, and won't erase the magnetism from the core.
    You don't want residual heat to melt your generator's copper windings insulation, if you shut down right after a heavy load.
    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 ,

  • Hairfarm
    Hairfarm Solar Expert Posts: 225 ✭✭✭
    Re: Wiring the 5K generator to my inverter AC INPUT.
    mike95490 wrote: »
    Beware ! Many generators "self energize" from residual magnetic fields in the core. If you leave a load connected when the motor spins down, you can erase that magnetism. Then you need to "Flash" the core.

    And when starting the motor, the power coming out of the generator is way off frequency, it loads the motor down - maybe preventing it from starting properly. (like starting your car with the trans in 3rd gear)

    The hard wired off-grid inverter/chargers solve this, by "qualifying" the generator for 30 sec or so, AFTER they meet the voltage/freq spec, and if they don't have a cool-down mode (to allow the cooling system to cool the motor and alternator down) for a couple minutes, they disconnect when the freq shifts out of spec, and won't erase the magnetism from the core.
    You don't want residual heat to melt your generator's copper windings insulation, if you shut down right after a heavy load.

    That's good to know. I'm going to check with Prosine about the "qualifying" voltage/freq spec, if any.

    Thanks