Electronic card noises/whistles

[Genotrom]

In the field I have several bizhub series 4/4e/8.
Older MFPs begin to emit noises/whistles from electronic cards. I believe they are the bobbins and the relays. Do any of you know any tricks to limit these noises, without replacing them?

[occus]

<Symptom>
In a very quiet environment and a machine get into the ready status,
buzzing/humming noise may come from DCPU (power supply)
TABT1300108EN**
DC for C224/284/364/224e/284e/364e or FUPU (Fusing power supply) for C454/454e.
<Cause>
Operation noise of the Noise filter for fusing heater lamp mounted on the
DCPU/FUPU may hear in that environment.
< Field action>
Please adjust the Heater control level under the Service mode gradually
up to the level 4.
>The setting change is reflected
and works by turning OFF/ON Noise filter
the main switch.

[Genotrom]

The problem comes exactly from the Power Supply. I raised to level 4, turned the MFP off and on again without much success. The noise is very random. What is meant by noise filter? thanks!

[occus]

The problem comes exactly from the Power Supply. I raised to level 4, turned the MFP off and on again without much success. The noise is very random. What is meant by noise filter? thanks!

The filter are copper coils but dont'replace.... i don't believe that is a solution.

Sorry unfortunately i have not more advice for you... the noise was also generated from every brand new out of the box 224e series. I can't remember but in the early state i think there was a special firmware and later the heater control level... are you up to date?

on 220 series only with firmware... but i had often light bulp flickering in the office with deactivated summing noise.

[Genotrom]

The filter are copper coils but dont'replace.... i don't believe that is a solution.

Sorry unfortunately i have not more advice for you... the noise was also generated from every brand new out of the box 224e series. I can't remember but in the early state i think there was a special firmware and later the heater control level... are you up to date?

on 220 series only with firmware... but i had often light bulp flickering in the office with deactivated summing noise.

I know so many problems of this type on C258 just out of the box (only this model. While C308, C368 and C458 never happened to me).
I happened to solve by putting a thickness behind the plate of the Power Supply but those were vibrations, not humming noises.

[qbert69]

Regarding my experience with high frequency noises/whistles, the only ones I've heard are from HV (High Voltage) devices such as flyback transformers in CRT type monitors and sometimes on the HV boards of copy machines. This is especially the case if it is a continuous frequency instead of a plastic against metal rotational sound. Many times caused by toner with its resin component getting stuck between say a metal shaft & plastic roller shaft hole. In effect the same as putting rosin on a horsehair violin bow & rubbing it across violin strings!!!

PS--sometimes the blade tips of spinning fans will create a high pitched noise based on the fan design & the rotational speed of the fan!!! And if you're prone to tinnitus, really messes with your hearing!!!

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