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Voltage High/Low Limits for new CyberPower UPS

CyberPower CP1350PFCLCD UPS
EVGA SuperNova 850 G2

I picked up one of these UPSs during Prime Day because the price seemed pretty damn nice and my current UPS could no longer handle my setup after adding another GPU...

Charged it up, plugged everything in, launched the CyberPower Power Panel software, ran some stress tests thru 3dMark and checked out my power draw, everything looks good. This unit should be plenty of power supply for my setup, with a nice little cushion to spare.

Now my question:

In the Power Panel app, under Configure --> Voltage, there are High/Low Voltage settings for when the UPS will intervene (default):
UPS intervenes when AC voltage goes BELOW 88 volts
UPS intervenes when AC voltage goes ABOVE 139 volts

This seems to be a little wide of a range to me, but that's just kind of my gut reaction. I was thinking of making it a little tighter, perhaps 95/135 or even 100/130... Can anyone shed some light on whether I am being too cautious or possible negative effects of tightening this range?

Thanks!!!
Reply to drewski989
9 answers Last reply Best Answer
More about voltage high low limits cyberpower ups
  1. You need to look at the range of voltages your power supply is rated for and how close to the amperage limits of the UPS you are. Lower voltage will require higher amperage for the same wattage. If your power supply is only rated to a low of 90VAC then you would want the UPS to intervene above that voltage for example.
    Reply to kanewolf
  2. I am stupid, the ability to expand the drop downs for the voltage range was disabled until I clicked the admin symbol, so I had no idea what ranges PowerPanel would allow you to set prior to posting.

    After I expanded the drop downs, 88 is the highest volts setting for the low range (i.e. it cannot be set to 89 or greater). 136 is the lowest volts for the high range.

    Thus, I decided to set to this:
    UPS intervenes when AC voltage goes BELOW 88 volts
    UPS intervenes when AC voltage goes ABOVE 136 volts

    I would still be interested to hear some feedback on what voltage range PSUs can handle. My thought is, a decent PSU must be able to deal with voltages within the 88-136 range without much difficult/risk, given the limited choices in PowerPanel.
    Reply to drewski989
  3. The only negative effect is that the UPS will switch to battery mode more often if voltage in your area isn't very stable. At my place it very rarely goes below 106 volts (the low transfer on my UPS).
    Reply to GhislainG
  4. drewski989 said:
    I am stupid, the ability to expand the drop downs for the voltage range was disabled until I clicked the admin symbol, so I had no idea what ranges PowerPanel would allow you to set prior to posting.

    After I expanded the drop downs, 88 is the highest volts setting for the low range (i.e. it cannot be set to 89 or greater). 136 is the lowest volts for the high range.

    Thus, I decided to set to this:
    UPS intervenes when AC voltage goes BELOW 88 volts
    UPS intervenes when AC voltage goes ABOVE 136 volts

    I would still be interested to hear some feedback on what voltage range PSUs can handle. My thought is, a decent PSU must be able to deal with voltages within the 88-136 range without much difficult/risk, given the limited choices in PowerPanel.


    The voltage range for the power supply will be listed on the specifications. 90 to 250VAC is typical for autoranging power supplies.
    Reply to kanewolf
  5. kanewolf said:
    You need to look at the range of voltages your power supply is rated for and how close to the amperage limits of the UPS you are. Lower voltage will require higher amperage for the same wattage. If your power supply is only rated to a low of 90VAC then you would want the UPS to intervene above that voltage for example.

    So given that explanation, there seems to be a gap. EVGA site states for this PSU:
    AC Input 100 - 240 VAC, 10A, 50 - 60 Hz

    If I am understanding properly, 88-100 volts from my outlet would be my no man's land voltage, in other words, the UPS would not intervene and boost, and the PSU is not within its spec'ed operating voltage.

    I am sure I am thinking into this way too much, but it is kind of an interesting topic, at least to me. I would think that the PSU would be OK to run at that voltage for a short time, and I don't live in an area with a history of brown-outs. So I am going to chalk this up to a needless worry.
    Reply to drewski989
  6. Why don't you set it to a range that makes you feel comfortable? My range (106 to 130) is much narrower than yours and my UPS rarely switch to battery mode.
    Reply to GhislainG
  7. GhislainG said:
    Why don't you set it to a range that makes you feel comfortable? My range (106 to 130) is much narrower than yours and my UPS rarely switch to battery mode.

    The software only gives me a range of 78-88 and 135-145 (approximately). Thus, I cannot even set it at 100 / 130. The most narrow range the PowerPanel allows is 88 low and 135 high (unless I am not using the drop down properly, boy I sure hope not).

    I am OK with setting it to 88/135, I am handcuffed by the CyberPower software I guess.
    Reply to drewski989
  8. Best answer
    drewski989 said:
    GhislainG said:
    Why don't you set it to a range that makes you feel comfortable? My range (106 to 130) is much narrower than yours and my UPS rarely switch to battery mode.

    The software only gives me a range of 78-88 and 135-145 (approximately). Thus, I cannot even set it at 100 / 130. The most narrow range the PowerPanel allows is 88 low and 135 high (unless I am not using the drop down properly, boy I sure hope not).

    I am OK with setting it to 88/135, I am handcuffed by the CyberPower software I guess.

    I see those exact same voltage limits in PowerPanel since I use a CyberPower 1500PFCLCD.

    Those voltage choice settings are only used to tell the UPS to switch over to battery backup mode when those voltage limits are encountered.

    When the PSU is plugged into the UPS, the PSU should never see voltages that low or that high because the UPS has an AVR (i.e. Automatic Voltage Regulation) circuit that is suppose to keep the UPS' outlet voltages within 12% of 120 VAC.
    Reply to ko888
  9. ko888 said:
    drewski989 said:
    GhislainG said:
    Why don't you set it to a range that makes you feel comfortable? My range (106 to 130) is much narrower than yours and my UPS rarely switch to battery mode.

    The software only gives me a range of 78-88 and 135-145 (approximately). Thus, I cannot even set it at 100 / 130. The most narrow range the PowerPanel allows is 88 low and 135 high (unless I am not using the drop down properly, boy I sure hope not).

    I am OK with setting it to 88/135, I am handcuffed by the CyberPower software I guess.

    I see those exact same voltage limits in PowerPanel since I use a CyberPower 1500PFCLCD.

    Those voltage choice settings are only used to tell the UPS to switch over to battery backup mode when those voltage limits are encountered.

    When the PSU is plugged into the UPS, the PSU should never see voltages that low or that high because the UPS has an AVR (i.e. Automatic Voltage Regulation) circuit that is suppose to keep the UPS' outlet voltages within 12% of 120 VAC.

    So after a little head scratching and re-reading your post, I think I get it. The AVR takes care of providing steady voltage when between the low value and high value setting. If the voltage goes either too high or too low for the AVR to correct, thats when it would switch over to battery to continue to provide constant voltage within range.

    By tweaking these numbers, I am basically trying to tell it at what point does AVR give way to battery. So, to go back to my "no man's land" comment, if the voltage coming into the UPS dipped to 95 volts, AVR would correct this voltage going to the PSU to be within an acceptable range of 120V... Only until the voltage dipped below 88, would the UPS stop using AVR and instead go to battery power. Thus, even though my UPS only switches to battery below 88 volts or above 139, AVR makes sure the voltages remain constant when the voltage from the outlet are within the set range.

    Thanks again to everyone who helped explain this, hopefully I am understanding it properly now.
    Reply to drewski989
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