# How to add an UPS beeper volume controller so that I can make it sound quieter when it beeps?

I've an EATON 5E850iUSBDIN 850VA/480W UPS.

This UPS makes a very loud beep sound both when it's first plugged into the mains(short beep) and when it's first turned on from the button(3x longer beep) (I'm not including the case when it beeps because the mains power is cut off).

I would very much like to somehow attach a volume controller so that I can make this beep quieter for two reasons:
1. thin walls - I worry about disturbing the neighbors with the loud beeping sound (mainly during the night).
2. this UPS constantly uses 7.5W even when nothing is plugged into it (this is after the battery is already well charged) - and due to 1. I'm keeping it plugged in full time. (as a side note: if I turn the UPS off from the button it consumes 7.0W constantly, even though the battery is already charged)

A volume controller would allow me to unplug it whenever I want thus saving power (and noise).

What kind of volume controller should I attach and where/how to wire it ?
and Would adding it possibly affect the UPS functionality ?

EDIT: picture of the beeper/buzzer inside:

• First you need to show us what kind of beeper it is. No it won't affect UPS functionality. Oct 26 '18 at 16:22
• Put some duct tape over it. Oct 26 '18 at 16:28
• While you have it open see if it has an opening that could be covered with a heavy tape such as insulation or duct tape. It might mute it enough. Oct 26 '18 at 16:28
• @Passerby,@Transistor interesting! Yeah that's the kind of buzzer! But I'm thinking that maybe I want to have it at full loudness during normal usage, just to make sure I hear it from where ever I am in the house. (added picture to Question)
– user201933
Oct 26 '18 at 17:08
• That type will be easy to mute acoustically with tape. Oct 26 '18 at 17:42

That's a common self osscilating Piezoelectric buzzer. You can lower the volume electronically by reducing the voltage to it. A few 1n4001 diodes in series would work. A low ohm resister in a pinch. Or you can just snip it off, or pierce the membrane inside with a screwdriver

But a mechanical method works fine too. Some tape over the hole, or some cotton in the hole. Both. Muffles the sound.

• What do you mean by "snip it off" ? I'm assuming that you're referring to the buzzer, then this means that the UPS functionality won't be affected if the buzzer were missing?
– user201933
Oct 26 '18 at 17:22
• I highly doubt there is any type of check mechanism for the buzzer. If it does not work you can easily add it back. To reduce the volume/voltage you would have to unsolder it or maybe one of the jumpers that lead to it anyway. But that's also why I provide the mechanical solution. It's much easier to just muffle it. Oct 26 '18 at 17:44
• Thank you, much appreciated knowing both methods! I have one B5K linear potentiometer. What's the (typical?) voltage over the buzzer ? I also have a 500ohm potentiometer but this one would require me to use a tiny screwdriver to change its value, so I will probably want to use the 5K one. I can probably use some wires to extend the buzzer to outside of the UPS case thru its vent holes. Am I correct in assuming that I can place the potentiometer in series with the +wire of buzzer?
– user201933
Oct 26 '18 at 18:23
• Yes you can put the pot in series. But actually moving the buzzer out the case would make it louder since the case isn't there to block some of the sound. Based on the relays there that are 12V activated, you may be looking at 12v or lower for the buzzer. Can't be sure without a voltage meter. Since the board does control mains voltage, you must take care when checking it. We also don't know the current of it, so we can't tell how much power your pot will take. Oct 26 '18 at 18:59
• I used the mechanical approach (the "both" version) because I didn't have the tools for precision-soldering. Works quite well, thanks so much to all that suggested it!
– user201933
Nov 2 '18 at 18:23

I know it has been a while, but I do hope that this answer will help those who don't want to tamper with the electronics.

the simplest solution I found was to drown the speaker in hot glue. just place the nozzle of the gun into that hole and fill the speaker with hot glue. it will muffle the sound to a point where you have to hold your ear against the unit to hear it. worked very well on silencing my EATON 5E 850I.