Trying to get an Outback vFX going

n1st

Hi folks,

First time trying to power up this inverter. It is connected to AC in and AC out, but not to a battery. I'm hoping I can get it to power the connected AC load on it with the AC in, until my batteries are ready to hook up to it. There's no sign of life what so ever. Any suggestions?

P.S. I have an installation and programming manual but neither explain how to use it or have trouble shooting. Is there an operation manual?

Cariboocoot

Re: Trying to get an Outback vFX going

No batteries = no inverter function. None at all. Not even pass-through because there's nothing powering the circuitry to tell the inverter there's power at AC IN and to switch the relay over. Nothing to switch the relay over with. Also no batteries to apply the charge current too, so it's just as well.

Did I mention it won't do anything without batteries attached?

snuffy

Re: Trying to get an Outback vFX going

Try the Outback users forum....http://www.outbackpower.com/forum/

n1st

Re: Trying to get an Outback vFX going

Thanks Cariboot.

Would you kindly explain how the negative pole of the battery bank is commonly grounded. Assuming that my system's ground is via the AC in ground line. Can I simply run a line between the "-" Battery connect and the AC in ground post?

Cariboocoot

Re: Trying to get an Outback vFX going

n1st wrote: »

Thanks Cariboot.

Would you kindly explain how the negative pole of the battery bank is commonly grounded. Assuming that my system's ground is via the AC in ground line. Can I simply run a line between the "-" Battery connect and the AC in ground post?

Gee, I don't know if I'm allowed to answer that. The new NEC GFDI rules say you don't do that anymore. Instead you install one of these expensive things: http://www.solar-electric.com/obdc-gfp2.html

Maybe I can say that in the old days we used to just run some 6 AWG from the battery (-) to the Earth ground rod and nothing very much bad ever happened as a result. :roll:

BTW you can get all the documents for Outback products off their web site:
http://www.outbackpower.com/resources/documents/

Yes there's operator's manual as well as installer's manual and programmer's manual. They got more manuals than .... Well, they have lots of manuals.

n1st

Re: Trying to get an Outback vFX going

Lots of rain here in CT!

Ok, I have more grounding questions. It's a little specific to my Outback vFX, but general enough to post here I hope.

So I understand that bonding ground to neutral is a no-no downstream of the main panel because current could flow on the ground line even when there's no fault. Yet the FX (according to my ohm meter) bonds the AC in neutral w/ the AC out neutral, and bonds the AC in ground with the AC out ground. So if the user bonds ground and neutral in the AC out panel (which I believe is customery), it in effect bonds the AC in ground and neutral - which is the no-no.

Is my understanding correct? How is this not a problem?

Cariboocoot

Re: Trying to get an Outback vFX going

Yes, AC Neutral IN connects to AC Neutral OUT and AC GRND IN connects to AC GRND OUT.
No, it is not a problem.

The problems arise when you have more than one bond between AC Neutral and AC GRND. There should be one bond only; at the main panel. Normally the main panel is fed by the inverter's output. The usual case where trouble arises here is with the generator, which sometimes has a Neutral-GRND bond which must be broken.

If this is being used as a back-up power for a set of sub circuits on a grid system, the Neutral-GRND bond is in the main panel that feeds the inverter's AC IN. Since both lines are carried through, the one bond remains valid and no additional bonds are needed. The AC GRND through the inverter is not interrupted, so the one bond remains.

For clarification, the problem with multiple bonds occurs when there is a fault: it creates alternate pathways which may not be the most direct route for sinking Voltage to Earth ground. You don't want it finding its own way; it will take the path of least resistance which could be the wrong one.

n1st

Re: Trying to get an Outback vFX going

Yes, the concern is I have is because the inverter is being fed from the main panel (from grid). So in this case, in the inverter's AC out sub panel, there should not be a bond between ground and neutral (because it's done in the homes main panel?

Cariboocoot

Re: Trying to get an Outback vFX going

n1st wrote: »

Yes, the concern is I have is because the inverter is being fed from the main panel (from grid). So in this case, in the inverter's AC out sub panel, there should not be a bond between ground and neutral (because it's done in the homes main panel?

That's right!

(There is a minimum 18 character post requirement which this sentence more than fulfills. It is not here for any other reason, so please ignore it. )

n1st

Re: Trying to get an Outback vFX going

Ugh 2 days without grid power, felt good to finaly take a shower.

Ok, another grounding question...
The backup system (panels, inverter, batteries, etc.) is grounded via the AC feed to the inverter (from the grid main panel). The line is only 12g.
Is that ground sufficient and if not, how would I wire a better ground without
breaking the single ground rule?

Cariboocoot

Re: Trying to get an Outback vFX going

n1st wrote: »

Ugh 2 days without grid power, felt good to finaly take a shower.

Ok, another grounding question...
The backup system (panels, inverter, batteries, etc.) is grounded via the AC feed to the inverter (from the grid main panel). The line is only 12g.
Is that ground sufficient and if not, how would I wire a better ground without
breaking the single ground rule?

Depends on what your talking about grounding.
You can run ground wire from the panel frames & mounts, charge controller case, and inverter case to the Earth ground rod using 6 AWG if you want. The two things that must remain "singular" are the one AC Neutral to Ground bond and one Earth ground point (which may be multiple rods/panels but if so should connected properly so it counts as one point).

Remember that during normal operation ground conductors carry no current. They are there for safety reasons. If a short occurs and power is sent to ground Voltage will quickly be sunk to zero, causing a sudden rise in current which should trip the breaker/blow the fuse and render the circuit safely inactive. For such an operation you don't need "full-size" wire to carry the load because the load should only be momentary. If you check out ordinary household wiring cable you may notice the ground conductor is smaller than the hot and neutral lines.

n1st

Re: Trying to get an Outback vFX going

Thanks for the grounding info.

Getting back to the original theme of the thread...

Even though the vFX it will not power up without battery, I noticed that it will continue to run without battery. What happened is that while running with batteries (full status light on) and AC in, I noticed the batteries were at 50.4 and not the 54.4 as the manual would indicate a 48v battery bank should be floated at. So, I disconnected the Batteries via the DC disconnect, and the vFX continued to operate (freaked me out a bit). The voltage at the vFX side of the DC breaker was ~56v - which really freaked me out until I realized it was the voltage from the vFX trying to charge the batteries.


So, a few questions:

Is it surprising that the vFX continues to run with DC disconnected?

There's a couple second quiet buzz after the DC is disconnected. Is this harmful to the vFX?

Why is the vFX floating the batteries at 50.4 instead of 54.4? I have not changed any defaults, and I don't have a mate yet.

Cariboocoot

Re: Trying to get an Outback vFX going

Do not do what you just did.

Is it surprising the inverter continues to "run" after the DC source is removed? No; once the circuitry has been energized the caps will hold enough power to keep the LED's lit and it will try to function until they discharge. If you keep it energized by feeding AC IN it will try to function as a battery charger (it will not invert). Only you've removed the batteries, which are an important part of regulating that function. Why would you do this? If you have the batteries, either leave them connected or leave the FX off entirely. It was trying to charge batteries that weren't there, and it is possible the momentarily high circuit Voltage could do damage (but they're pretty tough).

Without a MATE you can't see how anything is set or make any changes. The default charging Voltages are: ABSORB 57.6, FLOAT 54.4
But without the batteries it imply will not function correctly.

If you need to use AC from your gen to run the loads disconnect from the AC IN and AC OUT on the inverter and wire the gen directly to the load wires. Don't try to "fake out" the inverter's transfer switch.

n1st

Re: Trying to get an Outback vFX going

I disconnected the batteries via the dc breaker just to simply shut down the inverter. Whats the best way to shut it down? I guess next time I should shut off the AC then shut down the DC. Because there is no operations manual that I can find (only installation and programming), I assumed that shutting down the DC would shut down the unit since it wont start up without batteries connected.

I'm still wondering why when I have it running normally (AC in from grid, Batteries connected, a few 100 watts of AC load, it's floating the batteries (I think it's in float mode) at 50.4v.

Cariboocoot

Re: Trying to get an Outback vFX going

Without the MATE you really can't tell what's going on. They sell them without it because you can stack up several inverters and only need one MATE to look at them all (via the HUB connector).

For one thing, the MATE has the ability to turn off the inverter without your having to disconnect the DC.

You should definitely disconnect the AC IN if you're not using the inverter at all, although there's no reason to shut down the DC if you want to run from gen power; just let it charge.

For some reason Outback assumes that if you've read the install and programming manuals you'll actually know how to use it. This isn't so; there's nothing in any of that which gives a hint as to how to adjust parameters to better suit your needs, just how to adjust the parameters. I've been through it dozens of times and have yet to find any statement like "If ... then increase/decrease ..." or "Changing ... to ... will ..." It could well be that your unit is set to 50.4 Volts (according to whatever you're taking the readings with).

So for now if you want to shut it down disconnect the AC first, then the DC. It should happily turn off in a few seconds after it loses battery power. (There is a manual ON/OFF jumper on the main board, but it's a pain to operate; you need needle-nosed pliers and the steady hand of a surgeon to pull it or replace it. You can also wire in a separate ON/OFF switch there - see page 22 of the install manual.)

n1st

Re: Trying to get an Outback vFX going

I have a Mate on order - really looking forward to it. In the mean time, I could use a FX for Dummies manual.

I have yet another question - it's likely easy to answer, but complex to ask. I'll post it in the beginners section. Thanks for all your help.

Cariboocoot

Re: Trying to get an Outback vFX going

n1st wrote: »

I have a Mate on order - really looking forward to it. In the mean time, I could use a FX for Dummies manual.

I have yet another question - it's likely easy to answer, but complex to ask. I'll post it in the beginners section. Thanks for all your help.

Don't sell yourself short: a lot of people think the answers must be easy if only they knew them. The truth is, this is complicated stuff and it doesn't come easy - even to those who "already know" it. :roll:

System2

Re: Trying to get an Outback vFX going

I can confirm, the OutBack VFX will do *nothing* without batteries. It will not even close the bypass relay (normally open). This knowledge was gleaned from a hilarious battery maintenance session in an install where the bypass breakers were never installed.*

* names not given to protect the innocent and clueless 8)