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APC UPS Data Center & Enterprise Solutions Forum
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Posted: 2021-06-30 07:18 AM . Last Modified: 2024-03-07 11:15 PM
Hi All - I'm now on my 3rd replacement SCL500RMI1UC and at wits end..
The issue is that these units (operating in Australia with ~240v) all fail to return to normal/mains power mode after a power interruption and battery/backup mode kicking in. I've been around and around with support to try to understand why. All the diagnostics/logs show acceptable/tolerance mains power inputs.
The units simply just remain on battery mode after I remove (and then restore within 30 seconds) the mains power input. It will remain on battery mode (with valid/clean 240v input power) until it finally hits critical low battery level and shuts down.
Has anyone else seen this issue, and any advice for trying to get this escalated to design/engineering teams within APC rather than the logistic exercise of sending me replacement after replacement - where all serials have exactly the same behaviours.
Thanks in advance for any guidance!
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Posted: 2021-06-30 07:18 AM . Last Modified: 2024-03-07 11:15 PM
When you've plugged the mains back in but the unit is still running on battery, what does it say?
I only have experience with older SmartUPS units (and I'm in AU as well, QLD) but these had either a serial console or a network management card that would report the mains voltage the unit detected as well as the reason why it is running off battery, which could shed some light on things. Not sure if you can get that kind of info out of your unit.
Have you had your power at the UPS input checked to make sure there's not a wiring problem? I'm not sure how the units will behave if the active/neutral lines are reversed for instance, when most appliances will run without complaint.
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Posted: 2021-06-30 07:18 AM . Last Modified: 2024-03-07 11:15 PM
When you've plugged the mains back in but the unit is still running on battery, what does it say?
I only have experience with older SmartUPS units (and I'm in AU as well, QLD) but these had either a serial console or a network management card that would report the mains voltage the unit detected as well as the reason why it is running off battery, which could shed some light on things. Not sure if you can get that kind of info out of your unit.
Have you had your power at the UPS input checked to make sure there's not a wiring problem? I'm not sure how the units will behave if the active/neutral lines are reversed for instance, when most appliances will run without complaint.
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Posted: 2024-05-22 05:32 AM
Why is this marked as resolved?
I have the same issue..... We have a number of these deployed around the UK, and at four locations users are reporting they occasionally get an audible warning from the units for some time before everything just reboots. Support have been USELESS in helping understand what is going on.
So I found some time in the office this week to set a new one up before it is deployed, and connected to the Smart Connect port to see what I could learn. I opted to turn down the sensitivty from it's defauly most sensitive setting, then pulled the power to see what happended. Logs report the event etc, but restoring power did not fail back from battery.
This is not a UPS if it can't perform that essential task
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Posted: 2024-05-23 08:32 PM
I think they all got marked resolved when they imported everything from old forum software.
Did you extract the info requested in the last message from the devices? I think seeing the reason why the unit wants to stay on battery power could shed some light on things.
Have you tried swapping a working unit with a suspect unit? If the suspect unit works fine at a different location and vice versa, that would suggest some of your sites have wiring problems.
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Posted: 2024-05-24 03:24 AM
There is no info to extract, the event log only reports state changes, not the reasons for them. I have a brand new device on my desk, when I pull the power lead it fails over to battery, when I restore power, it stays on battery. The only way I have found to restore power is to long press the button on the front and perform a reset, which would end power to any connected devices, in the same manner as those I have deployed are doing by running flat.
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Posted: 2024-05-24 05:10 AM
Show me all the available tabs in the Smart Connect as it relates to the UPS power, power quality, transfer voltage.
There should be two logs available from events and input / output metrics. Please upload all of the information so it’s viewable on the APC Forum.
If you don’t have Power Chute Business Edition (PCBE) installed do so now. As this will offer more real-time monitoring, active faults, and error logs.
Report back once the PCBE has been installed. Let’s see if there are extra options available on the unit via PCBE. More specifically how the unit should behave once power is restored!
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Posted: 2024-06-04 08:59 AM
Main dashboard:
Event Logs:
The sensitivity is the only configureable setting:
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Posted: 2024-06-05 05:04 AM
This isn’t from PCPE / PCSS . . .
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Posted: 2024-06-05 05:04 AM
OK, have installed the PCBE agent and accessed the web interface to find the following:
It says there is an update available, but SmartConnect says it's up to date
Initial set up has a field for automatically returning to AC power when available checked:
......and yet it doesn't, just pulled the power and tested again
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Posted: 2024-06-05 08:04 AM
Please upload the images that are viewable on the APC forum. I see nothing but three triangles as these are not the supported image formats. ☹️
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Posted: 2024-06-06 02:04 AM
The triangles (according to my browser) mean the images are awaiting moderation so hopefully they'll show up soon.
There's definitely an option in there somewhere to set the voltage, at least there is with older units. If it's set to 230V or 220V then it's probably seeing 244V as too high and it doesn't want to switch back to the battery until the voltage drops back closer to 220/230V. My guess would be on the solution being finding the voltage setting and changing it to 240V.
On mine it's in the settings for the UPS itself, where your sensitivity high/low option is. There are a bunch of others options you should see there as well, like what upper and lower voltages to accept before switching to the battery, how long to beep before the battery is about to go flat, how long to wait when power returns before switching back on, etc. What I mean is there should be way more options than you're seeing in your screenshot.
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Posted: 2024-06-06 06:33 AM . Last Modified: 2024-06-06 06:44 AM
Images just showed up in the forum. I’m assuming these were taken while the unit was plugged into AC Mains as the image capture shows On-Line vs Battery.
Remove AC Mains again from the wall outlet. The system should now indicate the UPS is on battery and NOT On-Line.
Please confirm this and provide an image capture. The update available message you see relates to PCSS software please update the software to see if the missing tabs are now available.
Please download and install PCBE Power Chute Business Edition software. APC indicates only PCSS is available for use on your specific UPS model. Let’s see if that is true and there may be options as it relates to input voltage, upper / lower transfer, and power quality sensitivity.
If there is change the input voltage to match your region whether it be 220, 230, 240 VAC. If the power quality is available change it to low.
If the upper and lower input transfer voltage is available select the widest input range.
All of the above will determine if and when the AVR / Battery only mode will kick in.
Again, update PCSS and also install PCBE to see if it connects and allows other options / changes not available in Smart Connect / PCSS.
You may also see if PCNS works on this unit and the results. Report back what you see and observe with screen shots. 👍
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Posted: 2024-06-15 06:58 AM
The last images I shared were from PCBE, as is the following:
Everything appears to suggest it should recover when power returns, and yet it doesn't
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Posted: 2024-06-17 12:43 AM
I don't have a web interface handy at the moment but this screenshot I found on Google shows you the name of the options we're trying to find. It's the 'nominal output voltage' and the high/low transfer voltages that we think are set incorrectly on your unit. You're looking at shutdown parameters in your screenshot, but instead you need to look for the voltage configuration options.
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Posted: 2024-07-15 04:49 AM
I can see the settings you are referring to:
Despite the suggestion of a drop down on the output Voltage, non exists so I am stuck with this value.
The transfer voltages are editable, however all these settings control, is the conditions under which the unit fails over to battery.
My issue is that when one does so, it doesn't recover to AC when power is restored. I fail to see how altering the above settings has any bearing on that other than reducing the chances of it failing over to battery, which isn't a solution.
I need a fix that allows it to recover, in the manner that a UPS by it's very nature, should!
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Posted: 2024-07-16 07:09 AM
Have you contacted APC Technical Support as it relates to this issue?!?! If so what have they said or going to do besides replace the unit??
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Posted: 2025-06-25 11:27 AM
I am having the exact same issue to this , no solution , unbelievable that the a modern ups cannot perform the one task it is supposed to do , will go back to my old lead battery "analog" units.
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Posted: 2025-06-25 11:23 PM
I will never understand why people take the time to post a message complaining about a problem, but they don't bother to give you the information you need to help them fix it. Maybe if people complained less and put more effort into working constructively with those people willing to help, they would reach a solution much more quickly.
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Posted: 2025-06-26 01:43 AM
Have you contacted APC Technical Support to track and investigate this issue?!?
If not please do, if yes what was the reply??? As an aside this series of UPS models have been EOL replaced several times by APC because they are just garbage. 🤦♂️ 👎
Questions Ask . . . 👍
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Posted: 2025-07-01 02:09 AM . Last Modified: 2025-07-01 02:44 AM
We have the same issue. We have 20 x SCL500RMI1UNC and they are all doing the same thing. There is no option to set the mains voltage in these models, it's fixed for us at 230v but our line voltage is 246v. The unit will not return to mains power after line voltage is restored, even if it's just a quick brown out. The unit runs down the battery and then restarts then outlets and then the unit returns to main power and charges the battery.
Has anyone found a solution to this issue on this model.
We have a support case open
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Posted: 2025-07-01 06:04 AM
Support provided the solution of changing:
Power Settings Configuration - "Upper Power Limit" to 260 VAC
Sensitivity to "Low"
We will now test this to see if this worked
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Posted: 2025-07-01 08:44 AM . Last Modified: 2025-07-01 08:45 AM
As of this writing nobody reporting this problem on the APC Forum has taken the time to follow up and provide a status update! 🤦♂️
Given there are literally thousands of threads in this forum with people asking and complaining about a problem.
Only to fail to reply or offer a follow up it doesn’t surprise me in the least! 👎
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Posted: 2025-07-02 05:02 AM
So to follow up and it would be nice to mark my previous post as the solution, we have seen the issue stabilised by changing the setting mentioned. This issue seems to be that the SCL500RMI1UNC is fixed voltage output of 230VAC and higher line input voltages ~ 240VAC are seen by the unit as distorted and will not return from battery when utility voltage is restored. Changing the setting increases the bar and the unit seems to behave as expected. Our line voltage in some locations can be as high as 253V and as low as 225V in the same city. We never have any issues or need to change the settings on the lower utility voltages but the higher need the settings changed to function. Check you line voltages...
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Posted: 2025-07-02 09:52 AM
This so called solution was called out several posts up above. It’s not a solution vs a break fix to larger problem with this line of APC UPS! ☝️
This is why the first two generations of this series was quickly EOL and replaced. 🤦♂️
It’s simply a garbage product . . .
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Posted: 2025-07-06 04:40 AM
How did you change the Upper Power Limit? I can't see that setting in SmartConnect.
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Posted: 2025-07-07 12:52 AM
If available it would be via APC PCSS application. Remote configuration must be enabled on the system for control of the UPS via Smart Connect.
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Posted: 2025-07-08 12:06 AM
OK, so I got the answer from APC support.
Install PowerChute Serial Shutdown
Connect the UPS via USB A to USB A cable
In UPS Settings change High Transfer Voltage to 260V and Sensitivity to Low. Save.
I tried this out last night and was able to successfully test an outage situation.
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