Smart-UPS X 750VA annoying noise

[dahuafschmied_apc]

This was originally posted on APC forums on 1/22/2015

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hi,

can someone confirm that this kind of UPS (SMX750I) make this annoying noise (hear attachment) by design?

it was exchanged by apc today but the new one did it as well.

markus

[BillP]

This reply was originally posted by Angela on APC forums on 1/23/2015

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Hello,

Does the sound change when the load % on the UPS changes? What about if you enable/disable green mode?

[dahuafschmied_apc]

This was originally posted on APC forums on 1/23/2015

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hi

the noise is in normal-eco mode.
with batteries unpluged there is no noise.
i comes from the back part of the ups. near the extension battery plug.

no change on load changes. 
green mode / eco mode: i did not find any settings where to disable it.

am i the only one with this? 

by the way:
today apc started an new exchange. i will see if the new one is quiet.

[BillP]

This reply was originally posted by Angela on APC forums on 1/23/2015

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You'll be able to enable/disable green mode if your LCD menu is in Advanced mode and I think it is under Configuration. 

I'll ask someone more local to you if they have any feedback and specific to your case. I asked someone here who said it sounded normal possibly and that it could be something to do with the power supply and capacitors on the output.

In general, some noises are expected and others can be a product of a  distortion on the input power to the UPS or sometimes caused by the load on the UPS. Other times it can be a fan  or something.

[smargh_apc]

This was originally posted on APC forums on 1/23/2015

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On 1/23/2015 2:02 PM, Markus said:

am i the only one with this? 

No. Here is a previous thread: https://community.se.com/t5/APC-UPS-Data-Center-Enterprise/bd-p/datacenter-forum

Here is a YouTube video, with audio obviously, where I recorded two affected units side-by-side:

I had two SMX750I units with this "hissing" noise. When I was talking to Support I suggested that they raise this as a possible design issue with senior engineers. I doubt it's doing any harm to the components, but I'm not an electrical engineer, so who knows.

Since my problems, I've tried an SMX1500RMI2U and an SMX1000I which have both, thankfully, not had this problem, so *perhaps* the 750 is more likely to experience it. I would be curious how many APC support incidents mention a "hissing", "ticking" or "buzzing" (I know "buzzing" is very ambiguous) noise - this could potentially be costing APC a fair chunk of cash in RMAs.

[BillP]

This reply was originally posted by Angela on APC forums on 1/26/2015

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Because it stops when you disconnect the battery, it could also be from something within the DC bus or related capacitors.  I know the original poster is already working with support so I'll defer to them. Though, sometimes the units make different noises, most of  which are nothing to be worried about, but it often depends on the input power environment, load attached, and the actual % of load. If the noise  is not acceptable, then the support team would review the case and then provide a resolution.

[dahuafschmied_apc]

This was originally posted on APC forums on 1/27/2015

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hi

after again 5 days waiting i got a brand new UPS from APC. 🙂

Same noise again. :-(((

i would say this is a fundamental design flaw and all the SMX750I have the this issue. the noise comes from the yellow big transformer/coil in the back of the device. see attachment.
my next step is to return the ups and use my old (and silent) emerson ups again. it makes me sad that APC is not able to handle the problem. till now they were my favorite ups manufacturer. i sold about 200 pcs in the last 12 years.... but i am just glad that this was happend with my own ups and not at customers side.

[LeJPL_apc]

This was originally posted on APC forums on 1/28/2015

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I also have the same problem with my new SMX1000I units. They make exactly same annoying noise constantly.

I now have four SMX1000I units(two replacement units) waiting for return and refund, or replacement to another model.

[dahuafschmied_apc]

This was originally posted on APC forums on 2/2/2015

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now i returned all 3 ups to apc.

they promised me to find the problem and 

we will see...

[Fintan_apc]

This was originally posted on APC forums on 4/21/2015

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Hi All

Was there ever any resolution to this. I have just taken delivery of a SMX750i and it has the same noise.

Kind regards

Fintan

[dahuafschmied_apc]

This was originally posted on APC forums on 4/21/2015

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hi fintan,
APC is as silent as their UPS should be.
i have nothing heard from them!
nobody cares about this case. they promise you to fix it and look at it but: welcome to the world of money driven business.
we, the 0.02% of customers who have a problem with the noise are not important enough to care about.
i am really disappointed about APC.
you should return your ups to your dealer and buy a ups from an other manufacturer.

[Fintan_apc]

This was originally posted on APC forums on 4/21/2015

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Hi Markus

Thanks for the prompt response.

I have logged a call with APC in my area and will give them an oppertunity to offer support. If the issue persists, however, I will be forced to replace the unit with another manufacturers. It's a pity because I'm really chuffed with the unit other than the hissing noise.

Kind regards

Fintan

[pomolo_apc]

This was originally posted on APC forums on 10/16/2017

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Hello everyone,

My SMX1000I makes the exact same noise. Support replaced my unit twice already but they are all the same. Two years on from the previous post, they seem to have no clue.

Has anyone resolved the creepy hissing noise issue, or shall I just live with it?

Thanks.

[BillP]

This reply was originally posted by Cristian on APC forums on 10/17/2017

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Hi Robert , that kind of UPS are designed for a datacenter , always will have some noise , if you want an ups that dont make noise you can buy an BR1200G ( any back-ups type) that are designed for individual use,

regards

[pomolo_apc]

This was originally posted on APC forums on 10/17/2017

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Hi Cristian, thanks for your kind reply.

I repeatedly asked customer support if I can trade up my SMX1000I with another model (SMT1500RMI2U) and pay the difference but they told me this is not possible.

I am aware that the SMX1000I is designed for datacenters and that's precisely what I need, but I also know for a fact that other APC models designed for datacenters do not make this kind of whirling, sizzling, hissing, creepy noise, because I owned some and I am just currently replacing an older one which was perfectly silent (unless on battery power, and that's fine of course).

I was surprised by the noise when I first turned on the SMX1000I - never heard anything like it - and I thought to ask support if it was normal, just to be sure. They listened to audio recordings I made on their request and they told me that the kind of noise my unit makes is symptom of a defective unit.

So, they opened an RMA for me and sent me another unit, which of course was even louder...

Apparently, that was also defective - so they said, and they sent me another one, which is equally noisy, scratched on the outside, has a broken smartslot retention fin and even misses all accessories, cables and manuals from the box.

I am now awaiting shipment of the third replacement unit. Which of course will be equally noisy, I'm sure, and I guess I will have to live with it.

That's why I was asking if someone had found any way to mitigate the noise: browsing around the forum I found some random suggestions to tweak the options via the control panel, but everything I tried until now made no difference.

You know it's not just the fact that it's noisy... It is the kind of noise it makes: it really seems that it could blow up or catch fire any moment... it's just so creepy... and having support telling me they are all defective... well, that's plain disturbing.

Robert 

[BillP]

This reply was originally posted by Cristian on APC forums on 10/17/2017

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you can ask to APC RMA if they can change it for an older version of it ( sua1000i), maybe they have one of this , this version is not so noisy 

[smargh_apc]

This was originally posted on APC forums on 10/17/2017

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I see this is still an ongoing product design flaw. Very disappointing.

Robert: silent SMX1000 units do exist! I took a risk on another SMX1000I and it has been fine.

As I mentioned previously in this thread, I did once have a "crickety" SMX750I which was replaced. And replaced again. And then it was replaced with an SURT1000I, presumably because APC was getting annoyed with the cost of of repeatedly shipping defective units, and the maufacturing cost might not be that much different.

The SURT series does have a continuously running fan. It's certainly not silent. However! The fan is much nicer than the continuous "chirping" noise from the SMX series, and it should, in theory, last longer than an SMX due to having fewer points of failure.

In my original tickets a long time ago, I did actually ask for some input from a senior APC electronics engineer who could tear down a faulty unit to fully investigate, but nothing came of it.

Perhaps all the faulty SMX units are repeatedly travelling through the RMA testing/refurb facility until they all eventually end up with a customer that puts them in a noisy datacenter....

[BillP]

This reply was originally posted by Muri on APC forums on 2/12/2021

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6 Years later, the problem seems to persist. Just started a brand new SMX750I and there is this noise. I'm glad you already discussed it here, so I was quite sure to start an RMA exchange. I'll add my recording of the noise as well for future visitors.

[BillP]

This reply was originally posted by Muri on APC forums on 2/22/2021

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Got the exchange today, same noise (plus additional clicking every two seconds, even if the device is off!).

Sound files attached.

At least a statement from Schneider if this noise is hazardous (fire) would be nice.

Perhaps I'll keep this unit for now because I don't want many more exchanges...

[BillP]

This reply was originally posted by Hickman on APC forums on 2/27/2021

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In general, some noises are expected and others can be a product of a distortion on the input power to the UPS or sometimes caused by the load on the UPS. Other times it can be a fan or something.

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[BillP · Accepted solution]

This reply was originally posted by Muri on APC forums on 3/2/2021

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On 2/27/2021 6:14 AM, Hickman said:

In general, some noises are expected and others can be a product of a distortion on the input power to the UPS or sometimes caused by the load on the UPS. Other times it can be a fan or something.

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Can you please stop copy-pasting the same not-helpful answers over and over again?

It doesn't make me feel valued as a customer.