CyberPower SL750U: https://www.cyberpowersystems.com/product/ups/pc-battery-backup/sl750u/
We have several of the CyberPower SL750U battery backups for things like our fiber optic gateway, modem/router, DVR/STB, and wireless bridge. We're in a part of central Texas where we get the occasional power outage or dropout, most lasting a very short time. It's nice to not have these electrical devices (along with our two LCD TVs and backup PC) shut down or reboot during those times.
The units in question have an audio mute feature, which do most of the CyberPower UPS units, that will prevent the units from beeping every 30 seconds while the unit is on battery only (either loss of power or unplugged - turned on in both cases). When the power returns, we do get the two beep sound to let us know we're back on AC power (I'm okay with those beeps since they only happen when the power returns).
I have this mute feature turned on for each unit, and it has silenced the beeps until today. To be fair, nearly every outage has been of short duration, so today's nearly one hour outage was a different test. I'm not expecting to have all the TVs, DVR, STB, Blu-Ray players and backup PC fired up during the outages with these backups, although items like the gateway (on it's own UPS), the modem/router (on it's own UPS), and the wireless bridge can run an estimated 180-300 minutes each on the SL750U. If any of the other devices are on (as opposed to standby mode), we turn those devices off if the outage remains more than a few minutes.
About 10-15 minutes after the power went out, a couple of the units started beeping. But instead of the usual two-beep signals or continuous beeps, we were getting a quick sequence of exactly five beeps every minute or so. But not all units were doing this, and one of them that was beeping was powered on but had nothing plugged into it (I use it for the AC adapter for a laptop and some external USB drives).
I called CyberPower, and the technician never heard of this. It is not documented anywhere. I started to wonder if we were getting a very low voltage going through the house, not enough to cause any other AC device to flicker or try to power on, but enough to cause confusion to these UPS units. About the time I was going to unplug one of the beeping units to see if it would still do it, the power came back. I hate it when I come up with what is potentially a good idea and the moment has passed.
Anyone else with CyberPower UPS units ever experience the five beep syndrome? For all other needs, these units, which we've had for about 9 months, have worked exactly for what we wanted them for. I have read someone indicating that their SL750U would beep when they plugged a space heater into an adjacent room, but that individual also questioned the wiring in their house. Our house was built the first half of last year, so I would like to think that isn't our problem. Maybe with multiple units in the house they are somehow affecting each other. I am truly at a loss, and CyberPower's technician was no help.
We have several of the CyberPower SL750U battery backups for things like our fiber optic gateway, modem/router, DVR/STB, and wireless bridge. We're in a part of central Texas where we get the occasional power outage or dropout, most lasting a very short time. It's nice to not have these electrical devices (along with our two LCD TVs and backup PC) shut down or reboot during those times.
The units in question have an audio mute feature, which do most of the CyberPower UPS units, that will prevent the units from beeping every 30 seconds while the unit is on battery only (either loss of power or unplugged - turned on in both cases). When the power returns, we do get the two beep sound to let us know we're back on AC power (I'm okay with those beeps since they only happen when the power returns).
I have this mute feature turned on for each unit, and it has silenced the beeps until today. To be fair, nearly every outage has been of short duration, so today's nearly one hour outage was a different test. I'm not expecting to have all the TVs, DVR, STB, Blu-Ray players and backup PC fired up during the outages with these backups, although items like the gateway (on it's own UPS), the modem/router (on it's own UPS), and the wireless bridge can run an estimated 180-300 minutes each on the SL750U. If any of the other devices are on (as opposed to standby mode), we turn those devices off if the outage remains more than a few minutes.
About 10-15 minutes after the power went out, a couple of the units started beeping. But instead of the usual two-beep signals or continuous beeps, we were getting a quick sequence of exactly five beeps every minute or so. But not all units were doing this, and one of them that was beeping was powered on but had nothing plugged into it (I use it for the AC adapter for a laptop and some external USB drives).
I called CyberPower, and the technician never heard of this. It is not documented anywhere. I started to wonder if we were getting a very low voltage going through the house, not enough to cause any other AC device to flicker or try to power on, but enough to cause confusion to these UPS units. About the time I was going to unplug one of the beeping units to see if it would still do it, the power came back. I hate it when I come up with what is potentially a good idea and the moment has passed.
Anyone else with CyberPower UPS units ever experience the five beep syndrome? For all other needs, these units, which we've had for about 9 months, have worked exactly for what we wanted them for. I have read someone indicating that their SL750U would beep when they plugged a space heater into an adjacent room, but that individual also questioned the wiring in their house. Our house was built the first half of last year, so I would like to think that isn't our problem. Maybe with multiple units in the house they are somehow affecting each other. I am truly at a loss, and CyberPower's technician was no help.
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