My stereo won't turn on, unless inductance present perhaps?

Hi all...

I have a couple of items wired to my inverter. Receiver, tele, lights, ceiling fans.

I just noticed that my somewhat "high end" Onkyo stereo sometimes won't turn on. Sometimes it will click (internal relay) and everything on my "green circuit" will power off if I attempt--even with a fully charged bank. I imagine this stereo draws some high amperage--it's a VERY heavy receiver.

I have a 3000W pure sine inverter. I tried turning *everything* off on the "green" circuit and it still wouldn't turn on.

Then, I turned on two ceiling fans that are powered by the inverter as well. The Onkyo unit powers up every time. It never fails.

Thinking that the fans are nothing but big coils, I'm guessing that this must have something to do with the fan's inductance on the circuit at the inverters output.

Can anyone explain why?

Comments

  • CariboocootCariboocoot Banned Posts: 17,615 ✭✭
    Re: My stereo won't turn on, unless inductance present perhaps?

    Any chance your inverter is set to "search" or "stand-by" mode? In such a case sometimes things don't draw enough power to "wake up" the inverter. Switching on another load (especially a resistive one) can compensate.

    But I also recall an incident here with an electronically controlled washing machine that would not start under similar circumstances.

    And now my memory is getting shakey so I'll let sharper minds prevail. :blush:
  • drew4justicedrew4justice Solar Expert Posts: 36
    Re: My stereo won't turn on, unless inductance present perhaps?

    I don't think there's such a setting for search mode. It's an (don't quiver) AIMS 24VDC 3000W pure sine inverter. I tried to contact them yesterday and today with no luck, just voicemail. I'll keep trying and relay what I'm told. I'd like to hear any other's input as well.
  • john pjohn p Solar Expert Posts: 814 ✭✭✭
    Re: My stereo won't turn on, unless inductance present perhaps?

    Have a look in the MANUAL or the back of the amplifier and see its current draw and see if you can find its input fuse and its size. then post result here
  • john pjohn p Solar Expert Posts: 814 ✭✭✭
    Re: My stereo won't turn on, unless inductance present perhaps?

    What size batteries are connected to the inverter?
  • nielniel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: My stereo won't turn on, unless inductance present perhaps?

    is that a tube amplifier? what is the amplifier rated for in watts per channel and confirm the number of channels?

    i might add for you to try a small incandescent light bulb too to see if that works as well. try 15w night light style too if you have one.
  • MiamiSunriseMiamiSunrise Registered Users Posts: 22
    Re: My stereo won't turn on, unless inductance present perhaps?

    Let's get rrrrrrreaaaaadddyyy to inruuuuuuuush!!!

    The issue here is that your stereo contains a very large high current linear power supply, as any good class A or AB power amp should to deal with audio peaks without distorting or spilling junk between channels :)

    When the amp is first turned on, it starts up in protection and an analog or digital timer ticks off a couple of seconds to allow all the sources to stabilize and emit their vile, speaker rending thumps
    When the bootstrap timer expires, the power supply relay closes, admitting power from the transformer secondary to a bridge rectifier and a set of very large, discharged capacitors.

    Hungry capacitors.

    If you listen carefully, you will hear a really interesting BONG noise after the relay closes. This is the transformer vibrating as it kicks out many amps for one or more cycles to charge the caps. The limiting factors towards the magnitude of this inrush surge are only the internal resistances of the transformer winding, bridge diodes, and the equivalent series resistance of the caps. It's like a tsunami.

    The motor is opposing the inverter shutdown because it is mechanically acting as a flywheel and providing a slight generator action, opposing the rapid voltage drop as the amp plays Hungry Hungry Nichicons over there.

    The AIMS inverter is likely intolerant of an overload lasting even one full cycle. Usually the microcontroller in this type of inverter cans the output the moment it sees the output fall below the target 120Vrms at 100% duty cycle (on modified sine units) or a failure to track the target output waveform despite the output PWM being at 100% output... it usually gives up in leads than one half cycle!

    Solutions to the problem:
    Never turn the amp off. Some amps have more or less static draw than others, so this is not always pleasant to do. This is actually a lot more gentle on the amp than cycling on and off (bwoooonnnng)
    Use a class d amplifier. These usually feature a soft start on their internal switchmode psu and are very energy efficient. Not everyone is happy with these as some designs sound too harsh and sterile. Class T Tripath amps sound really good to me. Inexpensive D and T amps that will run right off DC are inexpensive and readily available should you want to play with some.
    Turn the fan on first? Yeah... why not.

    Believe me, as a broadcast engineer outside of my day job, I have seen far funnier quirks. There's one transmitter design I have worked with where a field modification was needed to deal with a reset quirk. The transmitter had totally separate ferroresonant power supplies for a +48 and +12 rail. The +12 drove the exciter and prestige amp stages and the 48 drove the final power amp stages. The 48 would fall flat in a jiffy upon power loss but the 12 and logic supplies would stay live for a few seconds. The control board would see this as a PA fault and set the transmitter state to "off ". If the power came back on in time, it would see the +48 returned after it thought it was already off and lock up completely, ignoring the remote commands to restart. The solution: add a small relay with 120v coil to open the logic supply when the AC drops. Derp. The "Harris Quality" sticker on top of that thing is very ironic.
  • drew4justicedrew4justice Solar Expert Posts: 36
    Re: My stereo won't turn on, unless inductance present perhaps?

    BINGO! You just won a FREE bucket of electrons!!! Thank you for nudging my neuron activity into action. It all made sense after reading your post.

    I figured it had something to do with too much draw rather than too little, especially since the other devices powered off when I tried turning on the receiver.

    Indeed, the amp does feature a TRUE 130 watts x 7 channels + the ".1" sub channel. It's not tube amp, but one of the 'old school' more sought after receivers in it's time because of the great characteristics of the amplifier. I'm not in front of the unit, but I *think* it's the 805 series.

    I do have grid power on an adjacent wall so I'll run an ugly cord across the corner of the room. It really won't be in the way.

    As for the AIMS manual, it pretty much came with a folded 8-1/2" x 6 card. Not much information given and I can't even seem to find a manual on their website.

    And to leave no question unturned, I have 4 Trojan t-105RE batteries wired in series @ 24V.

    Thanks everyone!
  • MiamiSunriseMiamiSunrise Registered Users Posts: 22
    Re: My stereo won't turn on, unless inductance present perhaps?

    From Spamazon's listing on the 805:
    Product Dimensions: 18.1 x 17.1 x 7.6 inches ; 64 pounds

    Yes. Probably 2/3 of the weight of the beast is that transformer 8)

    Oh, also, my apologies for speaking like a drunken sailor.
  • CariboocootCariboocoot Banned Posts: 17,615 ✭✭
    Re: My stereo won't turn on, unless inductance present perhaps?

    I, for one, am not surprised that the solution is, as usual, get rid of the AIMS canoe anchor and buy a real inverter. It never ceases to amaze me just how bad their products are. :roll:
  • drew4justicedrew4justice Solar Expert Posts: 36
    Re: My stereo won't turn on, unless inductance present perhaps?

    Cariboocoot,

    Which inverter would you recommend?

    I'm not grid-tie, otherwise I'd run with one of the Xantrex products.

    Curious to your opinion.

    Thanks!

    Drew
  • CariboocootCariboocoot Banned Posts: 17,615 ✭✭
    Re: My stereo won't turn on, unless inductance present perhaps?

    Drew;

    I don't know what your power needs are so it's hard to be specific. I will say that you're right in not choosing a Xantrex and paying for its grid-tie features when you don't need them. If you really do need the 3kW 24 Volt inverter you're looking at around $2,000 for a good one. A lot depends on if you need 240 VAC, built-in charger, et cetera. Exeltech has a 2kW 24 Volt unit around $1,300. From there you go up to the Outback 2.5 kW 24 Volt at about $1,700, the FX3524 for $1,850, the Magnum MS4024 for $2,000 +/- and then 240 VAC version for a couple hundred more. I know: a lot more money than the AIMS. :cry:

    Bargain electronics so often aren't. :roll:
  • drew4justicedrew4justice Solar Expert Posts: 36
    Re: My stereo won't turn on, unless inductance present perhaps?

    Thank you.

    I contacted AIMS and they want me to send the unit back. I'm told that they will send me another and if I have the same issue they will refund my $.

    I have been in correspondance with a member here who may be selling a Magnus MS4024PAE. I don't mind running 240V as my sub-panel has accomodations.

    He is offering it at a very generous price, but I don't know if I can produce the $ right now. Maybe if I follow through with AIMS and get my $ refunded.

    Drew
  • MiamiSunriseMiamiSunrise Registered Users Posts: 22
    Re: My stereo won't turn on, unless inductance present perhaps?

    I recommend you get an inverter that contains a nice heavy transformer. The Xantrex XW series meet this specification (and lead to me saying things that would make a sailor blush when I have to lift one of them). I'm not really familiar with the Magnums but they look like they'd be this type as well.

    Most of those inverters, faced with a huge inrush load, will just politely keep providing power as the transformer saturates and makes offensive noises for a cycle or two... but the power doesn't die out on you, spike, or do anything otherwise harmful.
  • nielniel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: My stereo won't turn on, unless inductance present perhaps?

    if you have the opportunity to get a working used magnum inverter at a good price you would not be disappointed with it imho. you can either sell the aims and apply that towards the magnum or keep the aims as a spare. i doubt you'll need the spare though.;)
  • dataman19dataman19 Registered Users Posts: 6
    Re: My stereo won't turn on, unless inductance present perhaps?

    Have you considered just putting a 300VA UPS on the stereo?
  • dataman19dataman19 Registered Users Posts: 6
    Re: My stereo won't turn on, unless inductance present perhaps?

    Ooops.. Just realized this is a really old post..
    ..
    Moderator : please don't assassinate me.... Soooo sooorrrryyyy/...
  • techntrektechntrek Solar Expert Posts: 1,372 ✭✭✭
    Re: My stereo won't turn on, unless inductance present perhaps?

    Don't worry, they won't hurt you. Much.
    4.5 kw APC UPS powered by a Prius, 12 kw Generac, Honda EU3000is
  • vtmapsvtmaps Solar Expert Posts: 3,739 ✭✭✭✭
    Re: My stereo won't turn on, unless inductance present perhaps?
    dataman19 wrote: »
    Ooops.. Just realized this is a really old post..
    ..
    Moderator : please don't assassinate me.... Soooo sooorrrryyyy/...

    An old thread seems just like yesterday to these moderators. Seriously, I am impressed by how many old posts these guys remember.
    --vtMaps
    4 X 235watt Samsung, Midnite ePanel, Outback VFX3524 FM60 & mate, 4 Interstate L16, trimetric, Honda eu2000i
  • nielniel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: My stereo won't turn on, unless inductance present perhaps?
    vtmaps wrote: »
    An old thread seems just like yesterday to these moderators. Seriously, I am impressed by how many old posts these guys remember.
    --vtMaps

    don't kid yourself as we forget far more than we remember. often times a search of the forum stirs the memory.
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