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Disconnect Boxes and Breakers => E Panel's, Disconnect Boxes and Breakers => Topic started by: Bonanza Bucko on October 28, 2013, 11:35:45 AM

Title: What the heck is the purpose of the AC /Generator switch on an E panel?
Post by: Bonanza Bucko on October 28, 2013, 11:35:45 AM
I have an MNE250STM.  On the left side at the top and next to the double Invert/bypass switch is another switch labeled "AC INPUT/GENERATOR.  What is the purpose of the switch and what happens when either side is selected?  I must use a generator now and then and I'd love to know what that switch is for.

Also if you found the answer to that anywhere in the E-Panel instructions please tell me----I find those instructions to be very incomplete.
Thanks.
Bonanza Bucko  in Baja California on a beach:-)
Title: Re: What the heck is the purpose of the AC /Generator switch on an E panel?
Post by: Halfcrazy on October 28, 2013, 11:57:09 AM
The Black Slider will byspass the inverter and run the input straight through to the output, So basically it disconnects the AC out on the inverter and then hooks the AC in to the AC out in the E-Panel

The separate breaker marked AC in is for the charger in the inverter it hooks the AC in bus bars in the E-Panel to the AC input of the inverter.

Ryan
Title: Re: What the heck is the purpose of the AC /Generator switch on an E panel?
Post by: Bonanza Bucko on October 28, 2013, 12:29:37 PM
Halfcrazy:
Thanks a bunch....but one more question:  I now understand what the AC IN means but what does the "GENERATOR" position of that switch do?
Bonanza Bucko
Title: Re: What the heck is the purpose of the AC /Generator switch on an E panel?
Post by: Halfcrazy on October 28, 2013, 01:57:43 PM
You mean the single breaker not in the black slider?
Title: Re: What the heck is the purpose of the AC /Generator switch on an E panel?
Post by: Bonanza Bucko on October 28, 2013, 02:13:21 PM
Halfcrazy:

Yes...the single one marked "AC In/Generator.  It sits to the left of the black slider,
Thanks.
BB
Title: Re: What the heck is the purpose of the AC /Generator switch on an E panel?
Post by: Halfcrazy on October 28, 2013, 02:39:27 PM
It is the input breaker for the inverter. It goes between the Input bus bar in the E-Panel and the Inverters Inout terminals. So it is there to stop the inverter from charging.
Title: Re: What the heck is the purpose of the AC /Generator switch on an E panel?
Post by: Bonanza Bucko on October 28, 2013, 03:32:53 PM
Halfcrazy:

OK I think I get it: (I am not schooled in electrical design)  If that breaker is up an on AC IN position the charger in the inverter/charger will use the AC coming into the E panel to charge the batteries.  But if that breaker is in the GENERATOR position the AC from the generator will go straight through to the loads. 

Is that correct or do you mean that putting that switch in the GENERATOR position will stop the inverter/charger from charging in all circumstances....such as when there is no generator connected to the E panel?

Title: Re: What the heck is the purpose of the AC /Generator switch on an E panel?
Post by: Bonanza Bucko on October 28, 2013, 03:46:51 PM
Halfcrazy:
Let me say that all again because I may have not communicated well enough:

Why would I put that breaker in the "AC IN" position and why would I put it in the "GENERATOR" position?   Or, what is the purpose of putting in either of those positions?

Thanks,
BB
Title: Re: What the heck is the purpose of the AC /Generator switch on an E panel?
Post by: Halfcrazy on October 28, 2013, 06:51:37 PM
I think there may be some confusion here.

Single breaker not in the black slide: up is on down is off, it connects the AC in of the E-Panel to the input of the inverter when on

Black slider. Up is normal down is bypass, This when Up connects the inverter to the AC OUT bus bars. When down it disconnects the AC Out and then connects the AC in to the AC out to bypass the inverter.

Title: Re: What the heck is the purpose of the AC /Generator switch on an E panel?
Post by: Bonanza Bucko on October 28, 2013, 07:02:36 PM
Halfcrazy:
Boy you can say that again!  Confusion reigns.  I have been talking with Tom Carpenter and I think I have discovered that the switch on my E panel to the left of the black slider is mislabeled.  It is shown in your new E panel manual as AC INPUT DISCONNECT.   On my E panel there is a label that says down is GENERATOR and UP is AC INPUT.  The whole purpose of my questions today has been to discover what happens when that switch is DOWN.

So please respond and tell me what you think.

Thanks,

BB
Title: Re: What the heck is the purpose of the AC /Generator switch on an E panel?
Post by: Halfcrazy on October 28, 2013, 07:08:32 PM
It is a switch so when it is down it is OFF. So to recap what I said above when it is "Down" it is OFF so nothing happens. When it is UP it is ON so the AC source be it generator or grid is then passed to the INPUT of the Magnum to charge batteries.

Ryan
Title: Re: What the heck is the purpose of the AC /Generator switch on an E panel?
Post by: Bonanza Bucko on October 28, 2013, 07:15:59 PM
Ryan:
Thanks.  That is all I ever wanted to know.  Also the switch is mislabeled and I will fix that.
Thanks a bunch.  Sorry to be so persistent.

Bruce AKA Bonanza Bucko.
Title: Re: What the heck is the purpose of the AC /Generator switch on an E panel?
Post by: tcva357 on February 15, 2014, 09:31:56 PM
I am a little confused my self so what your saying is the ac hot in lead comes from inverter and the ac hot lead out lead goes to to an alternate source AC say generator or grid.So if I choose not to use this is it best to unhook this wire on bus?

Thanks'
Tim
Title: Re: What the heck is the purpose of the AC /Generator switch on an E panel?
Post by: vtmaps on February 16, 2014, 04:40:12 AM
Quote from: tcva357 on February 15, 2014, 09:31:56 PM
I am a little confused my self so what your saying is the ac hot in lead comes from inverter and the ac hot lead out lead goes to to an alternate source AC say generator or grid.So if I choose not to use this is it best to unhook this wire on bus?

No!  When you have an AC source such as a generator, the output of the generator has to go to the AC input of the inverter/charger.   The reason for this is because the the inverter/charger needs AC power if it is going to be a charger.  When the inverter/charger is being a charger, it cannot be an inverter.  In order to have AC in your house (while charging) the inverter/charger has a transfer switch that passes the generator AC to the house.

Your inverter/charger also has an AC output.  The AC at the inverter output is either the AC that the inverter makes when it is inverting, or it is the AC from the generator.  It depends on the position of the automatic internal transfer switch, and that depends on whether the generator is on or off.

does this answer your question?

--vtMaps

Title: Re: What the heck is the purpose of the AC /Generator switch on an E panel?
Post by: Bonanza Bucko on February 16, 2014, 01:12:11 PM
vtmaps comment below is the most lucid one we have had here and it is finally getting to the bottom of the confusion so many have about those two switches on the upper left side of the Epanel....at least my 250 jobbie.

I think part of the problem is that, despite the clarity of vtmaps', comments there still is potential confusion that comes from this:

1.)The automatic internal transfer switch closes when the generator is connected and running (or power from the grid...or any AC input) thus sending the AC power from outside the inverter/charger to the load....house.  That is what Vtmaps has written.

2.)Then as Halfcrazy says, "Black slider. Up is normal down is bypass, This when Up connects the inverter to the AC OUT bus bars. When down it disconnects the AC Out and then connects the AC in to the AC out to bypass the inverter." So then why is that black slider needed since the inverter/charger has the automatic internal switch as in 1. above?  Or put another way....why would one want to bypass the inverter if there is no external AC power available?

Some of us are electrical engineers who assume other people will intuitively see what is happening and they, thus, fail to explain completely what they mean.....we are boneheaded electrical engineers.  But others of us make a living by communicating completely and we, thus, find it hard to see that some EE types are boneheads about the English language.  Our EE means "English Engineer" and not Electrical Engineer :-)
Title: Re: What the heck is the purpose of the AC /Generator switch on an E panel?
Post by: Halfcrazy on February 16, 2014, 01:24:24 PM
The Bypass slider is a service bypass. It is ONLY intended if there is an inverter failure or the inverter needs maintenance. As you point out it does the same thing as the internal relay.

So simply put:
The Single or 2 pole breaker behind the slider (Not in the Slider) connects the AC input bus bars in the Epanel to the AC input of the Inverter. So if it is UP or ON the AC from the generator or the grid goes to the Inverter. if it is DOWN or OFF it disconnects the AC input bus bards from the AC input of the inverter

The Black Slider has 2 positions:
Up or Run or Invert= Output of the inverter is connected to the AC out bus bars
Down or Bypass = Output of inverter is NOT connected to the AC out bus bars in the Epanel but the AC input bus bars do get connected to the AC out bus bars to bypass the inverter
Title: Re: What the heck is the purpose of the AC /Generator switch on an E panel?
Post by: Bonanza Bucko on February 16, 2014, 01:58:49 PM
Halfcrazy:
Wow...now I'm not Half crazy!  Thanks. 

I certainly wish your explanations were included in the owners' manual for the E panel.  That would have saved this tech bonehead from about a year's worth of wonderment. 

Our E panel and Magnum inverter are serving a house on a remote beach in Baja California, Mexico.  The nearest hardware store is 100 miles away and the closest electrician is 350 miles away.  The beach bums who populate the place are either tech idiots like me or drunk most of the time; I'm only that way part of the time :-).   We have internet via satellite but no phone and no other services of any kind; we have to do all out own installation and repair work on the house the electrical system, the water system (powered by the inverter, propane for showers and stove, salt water septic tank and etc. etc.  The house has systems that belong on a yacht.

So thanks again....you comments will help a lot.  I  have printed them so I can include them in the owners documents next time we go down there in about two weeks.

The place is so remote that we have had to fly there in our small airplane for the last 35 years before a new read was built in the last couple of years; the old "road" was almost impassible and it took about 10 hours to drive the 100 miles to the hardware store.  The runway is under water at the high tides twice a month and too wet to use for about two days either side of those tides; that means that nobody can just drop in to visit: NICE and when I was working the office couldn't ever "get" me...NICER.  The fishing and hammock laziness are superb, however. So I work/putter abound every day until about noon and then I read a trashy shoot 'em up novel in a hammock on the porch unit it's time for happy hour.  When we go fishing that is a real adventure because the fish don't know we are bad guys and want to eat them:-)  We have Whale Sharks cruising about twenty feet off the sand most of the year and we have FinBack Whales, smaller only that Blue Whales, coming into our bay in the spring with their calves.  We love the place.


BB
Title: Re: What the heck is the purpose of the AC /Generator switch on an E panel?
Post by: tcva357 on February 16, 2014, 05:51:52 PM
So in hooking up my e-panel,i need to run a circuit to the generator xfr switch from the ac out bus correct?Also say I want to use the inverter as a battery charger do I have to do anything to the inverter other then flip brkr down?I am assuming this back feeds the inverter to make it a charger.

Thank's

Tim
Title: Re: What the heck is the purpose of the AC /Generator switch on an E panel?
Post by: tcva357 on February 16, 2014, 06:47:34 PM
So I think I got it straight although not an engineer but a Electric Serviceman,the E-panel lead marked AC out goes to the Outback Inverter AC int?And the lead in E-panel marked AC in goes to the AC out on Inverter,i am assuming that what you can do is if you run a circuit in the AC out bus say from a generator you can backfeed inerter and use it as a Charger?Why is there only one neutral wire in e-panel?Inverter has AC in and out neutral?

Thank's
Title: Re: What the heck is the purpose of the AC /Generator switch on an E panel?
Post by: vtmaps on February 16, 2014, 11:14:43 PM
Quote from: tcva357 on February 16, 2014, 05:51:52 PM
So in hooking up my e-panel,i need to run a circuit to the generator xfr switch from the ac out bus correct?

huh?  what generator transfer switch are you talking about?  Maybe you should describe your system... Perhaps I don't understand what you're trying to do.  The generator output usually goes to the AC in bus.

Quote from: tcva357 on February 16, 2014, 05:51:52 PMAlso say I want to use the inverter as a battery charger do I have to do anything to the inverter other then flip brkr down?I am assuming this back feeds the inverter to make it a charger.

You don't need to do anything to any breaker in order to use your inverter as a charger.  When the inverter detects AC on the AC in bus, it will stop inverting and use that AC to power its charger.  At the same time it will (using its internal automatic transfer switch) pass the AC through to the AC out bus.

--vtMaps
Title: Re: What the heck is the purpose of the AC /Generator switch on an E panel?
Post by: vtmaps on February 16, 2014, 11:25:39 PM
Quote from: tcva357 on February 16, 2014, 06:47:34 PM
the E-panel lead marked AC out goes to the Outback Inverter AC in?  And the lead in E-panel marked AC in goes to the AC out on Inverter

I'm not sure what you mean by "lead".  The AC out from the generator goes to the ePanel AC in bus.  The ePanel AC in bus is connected (through a breaker) to the inverter AC in.

The inverter AC out is connected through the Bypass switch to the ePanel AC out bus.  The ePanel AC in bus is also connected through the bypass switch to the ePanel AC out bus.

If this description is not clear and you can't make sense of the ePanel wiring diagrams and instructions, I think you should get some local help wiring it up... You can ruin your inverter and/or your generator if you make a mistake.

--vtMaps