Constant fan on SUA1500RMI2U

[Anonymous user]

Actually, it's label says DLA1500RMI2U, but it's identical to my other SUA1500RMI2U. Is there a difference?

Anyway, recently had a problem with a totally dead SUA1500RMI2U which turned out to be the batteries and is now sorted. So well in fact that I purchased another.

However, as soon as I plug this one into the mains power (i.e. IMMEDIATELY), the fan comes on. CONSTANTLY. This does appear to be something of a 'bête noire' for APC and their UPSes with a lot of complaints regarding it and I understand why people complain. Computer manufacturers go to all that trouble making the darn things super quiet, but then when you need to ensure constant power to it, sounds like a hurricane under your desk.

Reading these forums to understand more about it, I've found the conditions under which the fan should be on, but NONE of them apply. There's NO load (nothing at all even plugged in), it's still at room temperature and in any case simply charging the battery shouldn't make the fan kick in because the other unit I have was totally silent while doing the same thing. So one of them must be misbehaving.

I tried 'brain-deading' it which went according to plan, but as soon as I plugged the power cable back in - fan whirrs into irritatingly noisy spinning mode.

So why on earth is this fan on constantly? I can leave it alone for a bit to see if it stops, but it's driving me nuts already.

[BillP]

In post #5 on this thread, I did mention the differences of a DLA unit versus SUA including the lack of sensitivity button option among a few others as you noted.

As far as what I can provide, I have not been able to dig up any further information throughout any of the posts on the fan behavior besides what I have commented a few times. I personally still think there has to be something wrong with this fan if it is so noisy when it is on that it is bothersome. I don't see how it would make sense to the engineering team to have the fan act differently besides either on/off or high/low but again I only say that based on my experience and what I researched earlier and not for absolute certainty (beyond the known differences that are fact). All of our current models (since around the time these were manufactured), have switched to high/low fan speeds and are always running to provide better cooling and it seems to only be a problem if they are faulty or dirty from my experience.  So my belief without seeing or hearing it is either it is stuck in a high mode and just noisier than the SUA since it does not go into high mode or something is wrong with it. I don't know if the level of information you're requesting is possible but I would suggest that you could also check with your local support and refer to this thread to see if they can drive it further, or I can send it to them since I have not had luck here in NAM getting what information you requested on these units. I guess either way, I will ask our EMEA support to look at this further and see what can be done from here since I haven't been able to provide the answers you wanted.

[Anonymous user]

I think we need to not concern ourselves with fan speed. On the SUA it is NOT running. On the DLA it IS running constantly which indicates something is clearly wrong with one of them.

I have an ethernet card in the SUA and could easily swap it to the DLA to check that. I'm using Macs, so PowerChute probably not an option. I'm quite happy to use a terminal to access the UPS over the network if we need to do that. Can I update them to the latest firmware?

[BillP]

DLA/SUA units are not firmware upgradeable unfortunately - only the newer SMT/SMX UPSs are.

I was concerned with your observations and the fan speed because it was not clear what your concern was initially. I wanted to make sure we knew that there was a change at some point years ago where we went from on/off to high/low because then, it might make sense that one UPS has the fan on all the time and the other does not. Either way and no matter what fan speed the particular UPSs offer, they should not be on loud enough for any situation where it is so distracting and annoying.

You can move the Network Management Card to the other UPS and obtain the logs off of it if you want but I have a feeling it won't show anything obvious to us. You'd also need to make sure you clear the event log or note in the log at least where you make the swap. The data log will automatically clear though when you uninstall it/power cycle the card, just the event log won't. The only thing I could see it showing perhaps is mis-reading something as you suggested earlier but I am skeptical on that being the problem based on my previous experiences. The only thing I have seen is if battery charge is maybe stuck at 96% or something and it still keeps trying to charge. (Instructions are here on downloading the logs from the Network Management Card -> How can I download Event, Data, Configuration, and Debug files from my Network Management Card? | FA...)

[Anonymous user]

Still trying to figure this out. I had occasion to power down the SUA completely for several days (no connected devices). On re-connecting power, starts humming, but no fan, even though it must be taking a slight charge for the batteries. When pressing the ON button, the fan starts and the self test runs, then it settles down and the fan shuts off. This seems entirely correct to me.

OTOH, the DLA unit's fan starts the moment it is connected to power and stays running whatever I do. ON, OFF, testing, brain dead, everything, the fan is always on - until it is unplugged from the mains power. Only then does the fan stop.

My only recourse seems to be to remove the top to try and figure what is wrong. So could Angela (or other APC personnel/expert), point me in the right direction. What sensors are in operation and where are they?

Otherwise I'm just going to have to unplug the fan. But I'd rather fix the sensor problem.

[BillP]

It definitely should not be running when it's braindead because braindead refers to a state when the UPS has completely discharged its capacitors and should be removed from AC. Not sure if that was just a typo.

By this behavior, it sounds like the fan is always but it also must be abnormally noisy. I am still convinced by what you've mentioned that there is a problem with the particular fan (bearing, dusty, etc) and then yes, maybe it is always on so it is more noticeable.

I know the schematics are proprietary so I don't even have access to them and we don't urge users to open the lids, regardless of warranty status but if someone else has information they would like to share, please do. I hate to see the fan unplugged in case things heat up..

[Anonymous user]

Trust me, it is NOT a problem with the fan itself. Having worked with computers for 30 years I know the difference between a fan being on and being off. The fan is not unusually noisy. As is normal for a fan, the loudest noise is that of air rushing through rather than any vibration or other noise of the fan motor itself. Just to be totally clear on this, The fan in the SUA comes on as previously stated and then OFF, wheres on the DLA it is ON the whole time. No question.

I might have been misleading when I said it was on even when brain-dead. What actually occurs in the DLA is that the fan continues running when power is unplugged and only stops when holding in the OFF button, i.e. brain dead. But when you then reconnect the power, the fan comes right back on.

The problem is that the 'system' is for some reason deciding that the fan should be on and that's what needs to be tracked down.

Am I right that these can be run with the battery out? If so, I'll swap the batteries between the 2 units and if the problem switches, the batteries need replacing. If it remains with the DLA, then it HAS to be something to do with the sensing.

I could really do with more info about the sensing and how it functions (or doesn't).

[Anonymous user]

Actually, it's label says DLA1500RMI2U, but it's identical to my other SUA1500RMI2U. Is there a difference?

Anyway, recently had a problem with a totally dead SUA1500RMI2U which turned out to be the batteries and is now sorted. So well in fact that I purchased another.

However, as soon as I plug this one into the mains power (i.e. IMMEDIATELY), the fan comes on. CONSTANTLY. This does appear to be something of a 'bête noire' for APC and their UPSes with a lot of complaints regarding it and I understand why people complain. Computer manufacturers go to all that trouble making the darn things super quiet, but then when you need to ensure constant power to it, sounds like a hurricane under your desk.

Reading these forums to understand more about it, I've found the conditions under which the fan should be on, but NONE of them apply. There's NO load (nothing at all even plugged in), it's still at room temperature and in any case simply charging the battery shouldn't make the fan kick in because the other unit I have was totally silent while doing the same thing. So one of them must be misbehaving.

I tried 'brain-deading' it which went according to plan, but as soon as I plugged the power cable back in - fan whirrs into irritatingly noisy spinning mode.

So why on earth is this fan on constantly? I can leave it alone for a bit to see if it stops, but it's driving me nuts already.

[Anonymous user]

Hi, the DLA model identifier indicates that this is a Dell UPS ( Rebranded -  APC is the OEM). I have several of these in the field and the only differences I have ever noted are that the power cords are detachable on the Dell models. As for the fan, its a case of "don't worry be happy"...I look after close to 400 ups and I am actually happy/relieved to see units that have constantly running fans because I know their lifespan will be maximized because they are always running cool inside...heat is the # killer or electronics...it causes capacitors to dry out, batteries to deteriorate more quickly, increases risk of thermal runaway as the batteries age, etc etc etc. This is rack mount ups which usually live in computer rooms and communications rooms where noise is expected....if you have no way of relocating it elsewhere in your office environment and have no choice but to want to run it under your desk I'd suggest using a hush-box.

[Anonymous user]

I hate fans running all the time and although this is intended for use in a rack, there's no need for constant fan and it is quite unacceptable.

However, the important point is that my other one (the SUA) has just had new batteries installed (as you may remember from that thread) and charged, yet at no time has the fan come on. Neither when just plugged into the mains, not when actually up and running. Not tried it when no mains power, but it seems to be operating exactly as it should. This DLA is not. It is acting in a different way, yet they should both be following the same rules. The fact they exhibit different behaviour is a strong indication one of them is not right. Since it is this DLA which is not conforming to the manufacturer's rules, I'd say it's this one which is wrong.

It's now been on about 3 hours and the fan is still going full blast. It's stone cold to the touch, there's nothing plugged into it (apart from its power cord) and not even on. It has to be an error somewhere.

[Anonymous user]

I cannot speak to your individual dislike of fan noise, but there are two other possibilities that could be at play here:

1. Dell may have asked APC to design their UPS for continuous fan operation, given that Dell branded rack mount UPS are more often purchased along with their server product and servers always have continuously running fans so sys admins would expect the fan to be running and would suspect a faulty unit if it wasn't.

2. The fan in your SUA1500 may have died.

[Anonymous user]

I don't think the fan in the other one is wrong, but I'll see if I can check.

Interesting point about Dell units being different. Could someone from APC perhaps comment on this. Would a Dell specific version have different fan control than a normal one?

[BillP]

For the Dell branded DLA units, the only changes were input plug types (some came with removable input power cords or different plug types), there was no ability to change the sensitivity via the little button on the rear of the unit, and lastly, they had a 3 year warranty instead of the standard 2 year warranty we give with the APC SUA Smart UPS that align with those DLA SKUs.

The fan operating parameters would not have changed on SUA via DLA but I know we changed the parameters at some point to have a high/low fan speed rather than just on/off. Take a look here -> Smart-UPS fan operation parameters | FAQs | Schneider Electric US

I want to say what determines "older" and "newer" SUA's is anything newer than 2008-ish where they changed from on/off to high/low.

We can verify the first six characters of the serial numbers on your DLA and SUA to see if one is older/newer which could explain this.

[Anonymous user]

Well here are the 2 units:-

• SUA1500RMI2U = AS0731332563

• DLA1500RMI2U = AS0748131967

The first one (as we discussed elsewhere) runs fine with new batteries with no unexpected fan noise.

The second one I just bought based on the behaviour of the first one, but as soon as the power cable is lugged in, the fan is on full speed making a lot of noise. It is unusable as it is in my home/office study. Would appreciate the help in sorting this.

[BillP]

Maybe we need to clarify - is the problem that the fan is on and/or too loud? Where as when the SUA's fan on it is not as loud? Do we potentially just have a faulty fan or is the concern that the fan is always on either high or low and the high speed is too loud?

[Anonymous user]

I'm not aware of any different fan speeds.

• The SUA is basically silent (apart from some slight humming) and the fan is obviously NOT running.

• The DLA fan runs constantly and very noisily. No idea if it hums as I'd never hear it.

[BillP]

Technically the fan is not replaceable or serviceable on these units but I mean the first thing we usually suggest if it is really loud when it's running is to clean it (like with compressed air) or see if something is stuck in it.

Beyond that I am kind of stuck on what to suggest besides replacing it (at your own risk) if it is not obviously dirty or broken. Maybe one of the bearings inside the fan is on its way out.

[Anonymous user]

That's not really the point Angela. The problem is that the fan is running at all. On the SUA it hardly ever runs. Just sits there doing its job without feeling the need to cool off. But the DLA fan roars into life as soon as the unit is plugged into mains power. As these are actually the exact same unit, one of them MUST be behaving incorrectly and since the fan should not behave like in the DLA, it must be that one which is wrong.

So what can be causing the fan to come on all the time? Is there a particular sensor that is misreading? Is there a known (or even suggested) fault that can cause this?

Like I said, it's frustrating as I bought this second unit on the basis of the first one, but it's behaving in a totally different manner. Why?

Do these units have 2 speed or single speed fans? Can we get to the bottom of exactly WHEN the fan should or should not be on and at what speed?

[BillP · Accepted solution]

Hi again.

Maybe I misunderstood - I was trying to see if your concern was with the fact that the fan was on at all when it shouldn't be or if you thought that it was not supposed to be on based on the UPS state (not charging, no load, etc) and was just too loud or even if you were just seeing on/off with the SUA and then saw a high/low with the DLA.

No matter if the UPS has a single fan speed or high/low, it should not be so loud (at least after initial power up) that it is distracting to you and more importantly, concerning. In doing a little research on when this fan speed changed with someone in the UPS group, it is not as easy as saying "All SKUs switched at this date." It seems to be based on the platform and firmware rev. Now, while I personally think and I think you'd also agree, that these units are likely on the same platform, I better double check with you the firmware revisions on each (if you're able to get them). With that, I can potentially have someone look them up to verify when single vs high/low fan speed was introduced for these two SKUs, if not at the same time for some odd reason. These are about 7 years old now so we just have to go back and review the changes on these older units. To get the firmware revs, we need to either use a UPS Network Management Card, PowerChute software, or even something like apcupsd if you're familiar with it to connect and verify. If this is not possible, it just might take me longer to have someone back track by the serial numbers to see what rev these should've come with since I don't have the capability to do so personally.

Either way though, it does sound like there is something going on with the fan - potentially related to something like you suggested - it misreading something some place, etc.

And as I noted, we have that Smart UPS Fan Parameters kbase that outlines when it should be on or not under normal circumstances.

I am not sure if determining when the fan is supposed to operate though will answer all of the questions because no matter what fan speeds these units are supposed to have, the problem is still that the fan is way too loud based on what you're saying for either speed/configuration.

Using something to log in to the UPS units could offer additional information (but I am not holding my breath for anything obvious based on my experience), for instance if the UPS is at 99% and thinks its charging and is somehow stuck in a high fan speed. But, you did braindead it which would be my first action to try and reset that type of thing...

[ivanavich]

An old thread which I came across when researching why my DLA1500RMI2U had fan running at full speed for long periods of time when for years it had been silent. During maintenance I found the batteries quite hot and some even expanding and cracking the outer plastics. They were Drypower 12V 9Ah from Battery World and designed for UPS's. I replaced them with aged tested Ritar 12V 9Ah batteries and ever since the UPS has been silent and back to its normal self.