inverter/charger + generator = SMOKE!

:cry:

Smoke was the result of my Xantrex HF1000 inverter/charger being connected with 'shore power' from my P3-3000 generator in my off grid cottage. It detected the 110Vac input, switched to 'shore power', and charged the batteries for a few minutes (already at 12.6 anyway), then disconnected from shore power, produced white smoke from the bottom of the unit and went back to inverter mode. It still works as an inverter with my pair of T-105's, but, doesn't detect 'shore power' anymore and now has an oily burnt electrical odor to it.

I'm normally pretty successful at these types of projects, but, clearly I'm lost in the fog(smoke) on this one.
Through the clouds of smoke I suspect either a manufacturing defect or a grounding problem.
Any ideas?
Anyone else have similar experience?

Here's the details I'd ask about if I were trying to answer this question:

No significant loads were running at the time, polarity was checked, double checked, and after the fact once the smoke cleared re-checked.

The unit was brand new, this was its first use.

On the 'shore power' input side I'm feeding the charger/inverter directly from one of the 15amp 110Vac outputs on the generator using a heavy 3-prong extension (can't get the polarity wrong). I think that the generator neutral is bonded to the frame, but am not certain. It doesn't have its own grounding rod or dedicated grounding connection of any sort.

The 110Vac output side the inverter is connected to the A/C distribution panel which has neutral connected to ground in the panel and takes its ground from whatever feeds it. In this case it'll be taking ground from the ground connection from the inverter. The panel isn't directly connected to building grounding rod.

The ground terminal on the HF1000 chassis is connected to the buildings grounding rod.

The HF1000 manual indicates that it utilizes the shore power ground when running on shore power and the chassis ground when running as an inverter so it would be using ground from the generator when on shore power.

Before installing the HF1000 the generator was frequently used to feed the distribution panel directly using the same heavy 3-prong extension from the same 15amp 110Vac output on the generator as used to feed the inverter/charger.

Lost in the fog (er um smoke).

Comments

  • System2
    System2 Posts: 6,290 admin
    Re: inverter/charger + generator = SMOKE!

    After more reading it looks like whoever set up the load panel should have isolated the neutral from the ground. That would allow me to feed the panel from the GFCI outlet on the HF1000 inverter/charger.

    Does this explain the smoke from the charger/inverter?

    :blush:
  • mike95490
    mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    Re: inverter/charger + generator = SMOKE!

    Neutral / Ground would have smoked the inverter part, is my guess, I don't know what would have cooked the charger section, maybe a basackwards factory capacitor?
    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 ,

  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: inverter/charger + generator = SMOKE!

    Apparently the Xantrex HF1000 is one of those Modified Square Wave inverters that you're not supposed to connect the neutral and ground on. Now we know why. :cry:

    Maybe time for a new inverter?
  • System2
    System2 Posts: 6,290 admin
    Re: inverter/charger + generator = SMOKE!

    Inverter function worked fine before connection to generator and after connection to generator. The hf1000 doesn't appear to care if the ground and neutral are connected. This however still doesn't explain the smoke when connected to the generator.

    Thanks.
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: inverter/charger + generator = SMOKE!

    The problem has to do with part of the AC output being connected to the (-) DC input. As long as the ground is 'floating' it isn't a problem. But I'll just bet that if you feed the gen into the charge circuit with its neutral/ground connected you get a nasty (-)-AC-Neutral-Ground loop that fries the inverter's charging section.

    You need to check the gen and see if it has "floating neutral" and make sure the ground isn't connected.

    Of course chances are pretty good that the charger is fried. Maybe time for a stand-alone battery charger?
  • dwh
    dwh Solar Expert Posts: 1,341 ✭✭✭
    Re: inverter/charger + generator = SMOKE!

    There is an install guide here. Has more info than the user manual:

    http://ca.binnacle.com/pdf/Freedom-HF-install-guide.pdf

    According to that:

    "AC shore power

    A source of 120 V, 60Hz sine wave alternating current is needed to provide energy to charge batteries and pass power through to AC loads. This source is usually the utility grid (power company) or an AC generator. An automatic or manual AC source selector switch can be used to switch between the multiple sources of shore power to the Freedom HF system.

    The AC source feeding the Freedom HF must have the neutral conductor bonded to ground. When the inverter passes shore power through, it will lift the bonding relay on the output and will rely on the input being bonded in order to ensure that the power delivered to a sub panel is properly bonded. See “AC Output Neutral Bonding” on page 1–9 for more information on bonding relay operation."


    And


    "AC Output Neutral Bonding

    The neutral conductor of the Freedom HF’s AC output circuit (i.e., AC Output Neutral) is automatically connected to the safety ground during inverter operation. When AC utility power is present and the Freedom HF is charging, this connection is not present, so that the utility neutral (i.e., AC Input Neutral) is only connected to utility ground at your source. This conforms to National Electrical Code, which requires that separately derived AC sources (such as inverters and generators) to have their neutral conductors tied to ground in the same way that the neutral conductor from the utility is tied to ground in only one place. Check the regulations for your specific application to ensure that the installation will comply with the necessary requirements. In other words, the AC Input Neutral and Output Neutral must be isolated from each other."


    And

    "7. Locate the terminal block.
    The two input terminals are labeled as follows:
    • AC Input (L)
    • AC Input (N)
    A separate screw is provided to connect the AC input ground (see
    Figure 1-5 on page 1–17)."


    And

    "5. Locate the terminal block.
    The two output terminals are labeled as follows:
    • AC Output (L)
    • AC Output (N)
    A separate screw is provided to connect the AC output ground."



    So...

    The inverter assumes that the load will get its AC from the inverter - which in inverter mode will bond neutral to ground internally, and in pass-through mode will assume neutral to ground is bonded at the source and will "lift" its internal neutral to ground bond.


    The AC input source MUST HAVE its neutral bonded to ground.
    The inverter MUST BE connected to the AC input source ground.

    The AC load MUST NOT HAVE its neutral bonded to ground.
    The inverter MUST BE connected to the AC load ground.

    The input ground and output ground are separate and connected to different screws on the inverter.


    Otherwise..."what's that smell?"
  • n3qik
    n3qik Solar Expert Posts: 741 ✭✭
    Re: inverter/charger + generator = SMOKE!

    How about the no-load voltage of the generator, could it be just a tad high ??
  • solorone
    solorone Solar Expert Posts: 257 ✭✭✭
    Re: inverter/charger + generator = SMOKE!

    What did support at Xantrex say. I had one of their early 4024 Trace units burn up due to a power surge when a genset ran out of gas. This problem had really not been identified or talked about at the time, they cut me a nice deal on a new one, but that was before Clyde and buds sold the place.
    Good luck, really hurts to loose the heart of your system.
  • RCinFLA
    RCinFLA Solar Expert Posts: 1,484 ✭✭✭✭
    Re: inverter/charger + generator = SMOKE!

    On this modified sinewave inverter, the charger is pretty much an independent separate circuit. The old DR and Freedom series had a power transformer that was used backwards with rectifiers for charging. The transformer made them heavy (45 lbs)

    The output has a DPDT switch that takes both plug prongs and flips them over to AC mains input so this solves the floating neutral requirement when the inverter is operating.

    Based on the weight of the unit (10 lbs), the charger section is a switching power supply. This is likely what 'smoked'. It is likely a separate module that can be independently replaced or repaired.
  • homerramirez
    homerramirez Solar Expert Posts: 102 ✭✭
    Re: inverter/charger + generator = SMOKE!

    One thing for sure did happen, you have an invercharger, as itself explain, both process are controlled by a relay, when plugged to the generator and you are using the inverter as power supply, the relay is trying to do both functions at the same time, if you were watching tv. when this happen you should see the picture (on tv) shrinking and expanding very fast, this is the relay switching between inverting and charging, what you should have done was turned off as inverter and let it do the charge part of the cycle or if batteries are full do not plug it to generator, I was lucky that my Samlex S-2024A had a beeping device and I was close while watching tv., for some reason they built this inverchargers in a way that if is off as soon it detects 120v. in, after few secons it does comes on as a charger but while charging detects a 120v demand (out) it tries to switch as inverter....you do no see this happen when invercharger is new, after months of using it is more likely to happen....

    wipe your tears off :cry: and is time to upgrade to a true sine:D

    by the way mine is a 2000w true sine Samlex.

    my 2 cts.

    good luck.
  • firefly
    firefly Solar Expert Posts: 66 ✭✭
    Re: inverter/charger + generator = SMOKE!

    Not sure if this is the same, but when the AVR went in my generator, when I was running it to bulk the batteries for equalization, it spiked from 120 volts to 187volts. White smoke appeared from my Satalite receiver, fried the circuit board.
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: inverter/charger + generator = SMOKE!

    This thread shows that sometimes it may be better to have a stand-alone battery charger rather than rely on one built-in to the inverter. It may not be as efficient (because the AC loads aren't switched to the gen), but it might be the better option in certain circumstance. Trouble is, you don't know when those circumstances might be - until the smoke comes out. :cry:

    I'm thinking of switching because of the heavy loads coming on unexpectedly and 'killing' the gen - causing a momentary power outage. I understand this is not good for the inverter/charger in any circumstances (repeated unexpected Voltage drop on the AC in).
  • dwh
    dwh Solar Expert Posts: 1,341 ✭✭✭
    Re: inverter/charger + generator = SMOKE!
    This thread shows that sometimes it may be better to have a stand-alone battery charger rather than rely on one built-in to the inverter. It may not be as efficient (because the AC loads aren't switched to the gen), but it might be the better option in certain circumstance. Trouble is, you don't know when those circumstances might be - until the smoke comes out. :cry:

    I'm thinking of switching because of the heavy loads coming on unexpectedly and 'killing' the gen - causing a momentary power outage. I understand this is not good for the inverter/charger in any circumstances (repeated unexpected Voltage drop on the AC in).

    For my camper, I had already decided to go the separate charger route. The main reason is that I will be using my battery bank in "UPS mode" (loads running from the battery while charging) and so I'll be running the converter/charger (almost certainly an Iota) in two-stage mode.

    This also allows me to size the converter/charger properly to the optimal (C/* + running load) rate that the battery bank requires - and to change it (add another charger) if I decide to add another couple of batteries.

    I will also be using a Battery MINDer on the engine battery, and I want that to be fed ONLY by generator or shore power - I don't want that running off my aux bank through an inverter.
  • System2
    System2 Posts: 6,290 admin
    Re: inverter/charger + generator = SMOKE!

    Thanks everyone for the input.

    I've returned the HF-1000 to Xantrex and they were good enough to ship me a new one. They weren't able to share the exact cause of the failure so I'm still not sure if it was a manufacturing defect or my install. Come spring I'll implement some of your suggestions and see what happens.

    Thanks again.