APC UPS CS 500 (BK500EI)

The fault indicator means that there is a fault in the circuitry of the UPS. It could be the control board or another part of the system. (If the batteries were bad, you would see the Replace Battery light illuminate.) If the SURT3000XL is under warranty, contact APC. The standard warranty period is 2 years for repair/replacement. Note: you'll probably have to pay for the shipping of the unit. If the unit is out of warranty, replace it with a new UPS.

I hope this helps.

Cindy Wells

press the button for 5 seconds, until the long beep, or there is a problem with the battery

there are 2 parts of a UPS .
the charge side
and (battery is obvious)
the inverter side.
if the charger fails, all is lost. (are the batteries in backwards?)
if the charger works (volt meter tells you that)
then the inverter is bad. (this unit is not full time UPS , but part time, this means it switches over to inverter at power fail.
(on full time sys. inverter runs full time, like the name states)
the unit, you mean the load right.?
the UPS side plugged into a load. and the load is now dead.

the Backup plugs should work if the mains are hot.
if you kill mains, the inverter will fire off, (hear the squeal?)
and give you 500 watts for some minutes, sucking the batteries dry. (see load run time curves)
I used to do service on HUGE UPS systems, some with 100s of batteries. 3 to 5kw too.
on ours there is a port on the rear , we connect and can
check everything "BEST brand" even charge voltage.
did you look on APC site for special software and connections?

the manual does cover trouble shooting, ever read that?
RTM? start there, its online, for sure.

mosfet

1. Four beeps every 30seconds (On Battery LED will be illuminated)
This alarm indicates that the Battery PowerSupplied outlets are now supplying battery power as opposed to power from theutility. If the UPS determines that the input utility power is unsafe for yourcomputer equipment, the UPS will switch to battery power.
Note: Ifthe power disturbance is brief, you may only hear one or two beeps.

2. Continuous Beeping (On Battery LED will beilluminated)
This alarm indicates that a Low Batterycondition has been reached and that the UPS will soon shutdown. Once the UPStransfers to On Battery operation, it can only stay on battery for a limitedamount of time. The UPS will sound this alarm about two minutes before thebatteries are totally exhausted. Once exhausted, the UPS will shutdown and turnoff its output power to your equipment. If you hear this tone you shouldimmediately shutdown your computer to prevent data loss or corruption.

3. Continuous Beeps for 30 seconds (BackUPS OFFICE 250 and 280 ONLY)
This alarm indicates the unit has detected anOverload condition after it has performed a self-test during start-up.

4. Continuous Two-Tone Beep
This alarm indicates a severe Overload wasdetected while the unit was on-battery operation. This tone will continue tosound until the unit shuts down.

5. Continuous Tone (On Battery LED will beflashing)
This alarm indicates that the battery-poweredoutlets are overloaded.

6. Continuous Tone (On Line and On BatteryLEDs flashing) Back UPS OFFICE 350,400, and 500 ONLY
This alarm indicates that an internal UPS faulthas occurred.

Contact APC Customer Service. They will help you resolve this. If unit is still under warranty they will replace it. There is nothing you can do to repair anything yourself. Sorry ... try calling 1-800-555-2725800-555-2725 for support from APC

Internal fault.

UPSs will beep when unplugged to tell you that the mains is off! Overload should reset if you disconnect both the load and the power.

it's shot, replace it

Your main control board is defective, you need a new unit.