Noisy charge controller

[eastpoint turbine]

 Can anything be done to the classic 150 to keep it from   BUZZING ALL DAY LONG
it only gets a break at night  and starts again with the sun.  Works beautifully otherwise

[ClassicCrazy]

Buzzing ?  Is the fan running ?  The fan on mine will run whenever the controller is charging at a large rate or there is a big load in the daytime.  So I am wondering if the buzzing is something wrong with the fan possibly .

But my controller and inverter are in the shed - used to have some of that equipment inside close by - much better off away so fans and other noises that the electronics make don't get annoying. Though you really get to know the equipment when you hear it talking during hot weather, or when it wakes up early in the morning , etc.  But I would rather sleep in sometimes !

[Vic]

eastpoint,

What version of FirmWare is this Classic running?

Is this "buzzing" kind of a soft musical note,  or more of a rattling BUZZZZZzzzzzzz?

As CC mentioned,  it could be a bit of a resonance from a fan,  or perhaps it might be that the Classic has moved the input voltage very close to the battery voltage,  which can cause the inductor/s in the Classic to make a soft "singing" sound.

Out of curiosity,  when the Classic is making this noise,  what is the PV input voltage displayed on the MNGP?  What is the Battery voltage?

Thanks,    Vic

[TomW]

I had one where the plastic duct for the turbo fan was loose and rattled or buzzed when the fan ran.  It is that plastic bit that sticks up on the right side of the unit.

If you push it with a finger and the buzz reduces it may need a dab of silly cone to firm up the attachment.

Just what I saw on one. Midnite Replaced it so I did not do that but it would have probably worked as a home remedy.

Tom

[eastpoint turbine]

 Thanks guys , at this moment classic says
IN=109.4                       BATT=25.5
WATT=1162                   46.8 amps
KWH=4.5                      BULK MPPT
 
  the buzzing is low not  but it "jumps " to about twice the noise at times
when i first had the cc i thought the buzzing was a fan , but from this "forum" it appears to be inductor buzz
Vic  what do you mean by firmware  and where would i find that

[eastpoint turbine]

I;ve just come from listening to the cc ,and what i heard sounded like both inductor and fan together  eg  listening i heard what sounded like the fan cut-out and the inductors still buzzing

[Vic]

Hi eastpoint,

Thanks for the added info.

From the main status display on the MNGP,  keep pressing the Status button about six  or seven or so times --  this should take you to a screen display that shows the Firmware date and revision number for the MNGP and the Classic.

If your Firmware  (this is the software code that runs the Classic and the MNGP) is fairly old,  there might not be the display information on the revision level of this Firmware.

Do you remember if your Classic has the Wizard that came up,  when you first turned on the power to the Classic?  If you did see the Wizard,  then  the Firmware is fairly old,  and should be updated.

Inductor buzz,  or singing,  happens sometimes when the MPPT Tracking get stuck with the Vin very close to the battery voltage.   There have been improvements in the Tracking algorithm with later versions of the Firmware.

When you hear this buzzing,  please look at the PV input voltage on the MNGP.  If this voltage is just barely above the battery voltage,  this is what is causing the buzzing.   Sometimes (at least with later firmware),  pressing the Enter button on the MNGP  will cause the Classic to begin a new Sweep ...  sometimes,  this new sweep will get the Vin back up to where it belongs -- at the Max Power Point.

And if the buzz is from the singing inductor,   try setting the Classic to Legacy P&O in the Mode menu.  This uses a slow Tracking algorithm,  which usually avoids singing inductors.

But,  if you have older firmware,  it is to upgrade to the latest firmware from the Midnite Solar website:

http://www.midnitesolar.com/firmware.php?firmwareProduct_ID=1

Hope some of this helps.  Please let us know how you are doing.   Vic

[Vic]

OK,  eastpoint,

There are two sets of fans.  Two inside the Classic,  and the Turbo fan that is on the upper right side of the Classic (this is the one that TomW mentioned).

If you go to the Temps page on the Classic,  you will see the FET Temp.  If this above about 55 C (or so ...  forget)  the Turbo fan can be running.  This fan makes more noise than the internal fans.  If the environmental temperature,  where the Classic is located is fairly high,  the internal fans might run constantly,  and the Turbo will probably cycle on,  and off.

Also,  from the info you posted earlier,  your input voltage is fairly high,  especially for a 24 V system.   This causes a bit more heating in the Classic,  as this voltage ratio is high,  causing the Classic to work a bit harder in converting down to the low-ish battery voltage.   FWIW,   Vic

[tecnodave]

East point,

I had a buzzing issue with my Classic 150,  looking into the wiring compartment at the bottom I could see the lower fan wire touching the fan blade,  I solved by removing the fan tray from the back of the Classic bottom chassis and dressing the wires a bit and using a bit of silli cone to fix them clear of the blades......presto a quietly humming fan which is noticeable but not loud.

td

[boB]

Yes, all great ideas.  Since your input voltage is fairly high compared to the battery voltage, I do
not think it is coming from the inductors.  If it were, the you could just turn off LMX (Low Max) in
the TWEAKS menu to keep that from happening... (usually works, anyway)

The turbo fan is normally the fan that makes noise if it's going to.
That turbo fan plastic housing is probably the least "precise" component in
the whole Classic.  What happens sometimes is that the top and bottom half of
those pieces vibrate to the tune of the fan spinning.

How we usually fix that is to put a dab of RTV silicone sealant in-between the two halves.

Chewing gum would most likely work for a while too if you don't have any silicone sealant.

boB

[Westbranch]

Got any pics boB? Would a dab on the outside work rather than taking the fan apart? (I inferred that from 'between the 2 halves')

[tecnodave]

I am pretty sure boB was talking about the two halves of the turbo fan housing, not the fan itself, and they are a bit of a loose fit so dabs of silicone will dampen vibrations

td

[Westbranch]

Hi TD, I did meant the housing when I used the term fan...     I guess I used 'Fan' a bit too loosely

[eastpoint turbine]

  Thanks for the ideas/suggestions, looks like i'll have to abide with this noise even tho i've gotten them a bit quieter. I took the plunge to strip the cc,  clean the fans quite a bit of dust collected on them . Would you believe i could not recall whichside the turbo fan was facing ?  It cost me a call from the caribbean to the tech at Midnite  (good thing it was not midnight)
  I hope the mew models of classic are quieter. Thanks again
Eastpoint

[Robin]

We are just now going to start using silicone in four places on the turbo fan instead of one. Take a look at this picture. We also add a bit of silicone along the edge between the top and bottom turbo case about half way down the side.