Humming inside the TT

[Yosemite_Sam1]

Not that it bothers me or keeps me awake, but what is that humming sound inside the RV when the shore electricity is plugged in?

[PaulJ2]

One cure in the electronics lab to stop the "singing" was to jam an ice cream stick or a tooth pick into the transformer. Between the core and the windings.
Usually did the trick.

[Yosemite_Sam1]

2edgesword wrote:
A picture of a WFCO 8955 converter. There appear to be a number of components in the converter that can "sing" under the right conditions.

I must reprogram it to sing to my playlist, lol.

Thanks for the info.

[2edgesword]

A picture of a WFCO 8955 converter. There appear to be a number of components in the converter that can "sing" under the right conditions.

[myredracer]

FWIW, here is our old WFCO converter on the left (and new PD replacement on right). I spy with my little eye a small transformer and two toroidal core type transformers (or chokes). Note the larger transformer in the PD converter (and 2 fans instead of one). The WFCO failed in only it's 3rd season. Cheap junk...

[wnjj]

SoundGuy wrote:
Only an engineer would care :R - my point is that while converters used in RVs many years ago used to have heavy transformers the current crop built in the last 20 yrs do not. No transformer = no transformer hum, so that's not the OP's problem. 😉

You make it sound as if I was splitting hairs. You still say there are no transformers in them now which is completely false. There are transformers, perhaps not as large as in the olden days, but they are there and can still hum. The following two posts "sound" a lot like transformer hum to me which will be louder under higher load conditions. But alas, you will always have the final word and will need to be right so please spin this however you see fit.

RTCastillo wrote:
Update: It did stop apparently after the battery is fully charged with the longer drive.

Cecilt wrote:
Ours would hum when we turned on the lights. Once we switched out all the bulbs to LED's the humming stopped completely.

[Yosemite_Sam1]

Cecilt wrote:
Ours would hum when we turned on the lights. Once we switched out all the bulbs to LED's the humming stopped completely.

The LED lights were all off in my case.

But curious and might check this out some day, lol. So like the old florescent lights of old.

[Cecilt]

Ours would hum when we turned on the lights. Once we switched out all the bulbs to LED's the humming stopped completely.

[Yosemite_Sam1]

Update: It did stop apparently after the battery is fully charged with the longer drive.

The RV came from a month of storage although the battery still has some power left.

Thanks everyone for the input and oh the jokes. Love it all!

[Yosemite_Sam1]

Mfan wrote:
Is it the same song over and over?

Lol, you are not suggesting it's just inside my head, are you?

[Yosemite_Sam1]

midnightsadie wrote:
its mother hubbard and her family of mice .

I would dread that, lol. I clean up my RV of food stuff before I put it on storage. Got some ants and I was relieved it did not build a colony out there.

[2112]

Could be the fan. Mine at low speed, when lightly loaded, sounds like a hum to me.

[SoundGuy]

rrupert wrote:
The transformers in converters can have an AC hum.

SoundGuy wrote:
Converters for many years now have been all solid state and don't have any transformers in them.

wnjj wrote:
Solid state doesn't necessarily mean there are no transformers.

Only an engineer would care :R - my point is that while converters used in RVs many years ago used to have heavy transformers the current crop built in the last 20 yrs do not. No transformer = no transformer hum, so that's not the OP's problem. 😉

[Yosemite_Sam1]

SoundGuy wrote:

rrupert wrote:
The transformers in converters can have an AC hum. The plates can vibrate from the magnetism generated by the wire coil. It sounds like the humming that comes from florescent lights.

Converters for many years now have been all solid state and don't have any transformers in them.

The answer as to why the converter hums is obvious - it doesn't know the words. 😛

Lol, that made my day!

[wnjj]

SoundGuy wrote:

rrupert wrote:
The transformers in converters can have an AC hum. The plates can vibrate from the magnetism generated by the wire coil. It sounds like the humming that comes from florescent lights.

Converters for many years now have been all solid state and don't have any transformers in them.

The answer as to why the converter hums is obvious - it doesn't know the words. 😛

Solid state doesn't necessarily mean there are no transformers. In fact that usually refers to not having mechanical devices like relays. Switching power supplies have at least two transformers: 1 to reduce the incoming line voltage down to lower levels before converting to DC and another that is used in the switching. PD's patent has the word "transformer" 93 times. https://patents.google.com/patent/US7782002

That initial step-down transformer will be switching at the 60Hz line frequency and could hum some, though probably not loud like a large high voltage circuit breaker panel.