Generac 17.5kw broken down

oil pan 4oil pan 4 Posts: 753Solar Expert ✭✭✭✭
My 17.5kw generac has been broke down for a while now, the generac repair place doesn' know what to do.
I miss having my generac, it's 922cc 30hp engine and electronic speed control would easily handle loads that beat upother generators and take their lunch money. Loads like a transformer stick welder, big 3.5hp air compressor and my plasma cutter, it can easily run the air and the plasma at the same time.
The problem started when I removed the neutral ground bond to do main panel tie in.
It wouldn't start, because the fuel shutoff solenoid wouldn't open. So I pulled the fuel solenoid armature, then it started and tried to over speed, while not producing any voltage. When it does run at speed it only make 3 volts line to line so it has no excitation.
I restored the neutral ground bond but the damage was already done.

I think it fried the AVR. The electronic speed control needs around 90 to 120v AC to get a signal to speed reference.
I think if I power up the armature while it's running with batteries to create 100v or higher power the speed control should pickup. That would prove the AVR is bad and the speed control is good.

If it is the AVR then I don't want to put another gererac POS on there. For 2 reasons.
One it fried when I broke the neutral ground bond and 2 a new AVR is $160. You are supposed to break the neutral ground bond to to panel tie in.
I would like a different AVR, cheaper, but can make enough field power to get at least 50 amps out of my stator.
If the speed control is fried too I will remake it with a universal speed control and actuator, it will cost a little more than the generac control board, but at least I will be able to get parts for it.

It's kind of hard to think about doing off grid when your big generator is broken. I have a little 7kw it's easy to work on but it's seriously lacking the power of the big one.

Solar hybrid gasoline generator, 7kw gas, 180 watts of solar, Morningstar 15 amp MPPT, group 31 AGM, 900 watt kisae inverter.

Solar roof top GMC suburban, a normal 3/4 ton suburban with 180 watts of panels on the roof and 10 amp genasun MPPT, 2000w samlex pure sine wave inverter, 12v gast and ARB air compressors.

Comments

  • DanS26DanS26 Posts: 235Solar Expert ✭✭✭
    (Mods...if this is unacceptable advice...just let me know)

    Have you tried the Ziller forum?  Very good bunch of guys over there that know Generacs inside out.
    18.2kW Kyocera panels; 2 Fronius 7.5kW inverters; Nyle hot water; Steffes ETS; Great Lakes RO; Generac 10kW w/ATS, TED Pro System monitoring with PVOutput.org
  • mike95490mike95490 Posts: 7,923Solar Expert ✭✭✭✭
    Look at Central Georgia Generator   http://centralgagenerator.com/ 
    They have  video on their home page about ground and neutral.  They also sell many types of AVR's which the antique generator community uses a lot of.

    Also, you "Flash" the windings with a quick DC pulse, while things are static (not running)
    http://www.dieselduck.info/machine/03 electricity/flashing_generator.htm  or
    http://www.davidsonsales.com/FlashGenerator.htm
     I would not use instructions that have the machine running.

    residual magnetism is lost if the generator spins down with a load connected, switch the breakers off, let the engine idle a couple minutes to cool down, then shut it off, without any loads applied
    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 ,

  • BB.BB. Posts: 27,931Super Moderators, Administrators admin
    edited January 6 #4
    Did you reconnect the neutral to ground bond?

    Some ups (backup inverters) would not auto start if the neutral bond is open.

    Bill

    PS: Any useful information, even off forum, is fine.
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • oil pan 4oil pan 4 Posts: 753Solar Expert ✭✭✭✭
    I don't have a loss of residual magnetism since it's over 3 volts, plus one of the features is it has field boost that sends something like 6 volts of battery power through a resistor to the field every time it builds up volts.

    Yes I reconnected the neutral ground bond, but it would appear the damage is already done.

    I worked on big generators in the air force, I flashed a lot of fields because the crew chiefs liked to turn off the generators under load.

    Solar hybrid gasoline generator, 7kw gas, 180 watts of solar, Morningstar 15 amp MPPT, group 31 AGM, 900 watt kisae inverter.

    Solar roof top GMC suburban, a normal 3/4 ton suburban with 180 watts of panels on the roof and 10 amp genasun MPPT, 2000w samlex pure sine wave inverter, 12v gast and ARB air compressors.

  • oil pan 4oil pan 4 Posts: 753Solar Expert ✭✭✭✭
    I posted the question on ziller electric, no one responded and then 2 days later they deleted my question.
    Guess I exposured a massive design flaw.

    Now I think I need to do a detailed redesign of their generator. Showing how to rip out the dewply flawed, way over priced OE AVR amd replace it with one that probably isn' any better but is a heck of a lot cheaper.

    Solar hybrid gasoline generator, 7kw gas, 180 watts of solar, Morningstar 15 amp MPPT, group 31 AGM, 900 watt kisae inverter.

    Solar roof top GMC suburban, a normal 3/4 ton suburban with 180 watts of panels on the roof and 10 amp genasun MPPT, 2000w samlex pure sine wave inverter, 12v gast and ARB air compressors.

  • DanS26DanS26 Posts: 235Solar Expert ✭✭✭
    Your post on Ziller was not deleted but moved to the proper forum.....Guardian Portable Gasoline Generators.    And you did get a response:

    http://zillerstore.com/forums/showthread.php?t=4901

    18.2kW Kyocera panels; 2 Fronius 7.5kW inverters; Nyle hot water; Steffes ETS; Great Lakes RO; Generac 10kW w/ATS, TED Pro System monitoring with PVOutput.org
  • oil pan 4oil pan 4 Posts: 753Solar Expert ✭✭✭✭
    Oh I didn' know it was considered a gardian portable. I didn't get any private message saying it was deleted or moved.

    Solar hybrid gasoline generator, 7kw gas, 180 watts of solar, Morningstar 15 amp MPPT, group 31 AGM, 900 watt kisae inverter.

    Solar roof top GMC suburban, a normal 3/4 ton suburban with 180 watts of panels on the roof and 10 amp genasun MPPT, 2000w samlex pure sine wave inverter, 12v gast and ARB air compressors.

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