APC 500 UPS continuous beeping and flashing power on led problem solved

APC 500 UPS continuous beeping and flashing power on  led problem 

If  your back up ups giving a constant tone, tone  with the power on green LED flashing

For these kind of problems due to 1. battery  2. over load 3. relay 12v  4.  internal smps 5. IRL 3803 mosfet leakage or damage.

1 UPS BATTERY PROBLEM

If your not using long time ups without connecting AC or standby mode then internal UPS  battery may damage. if your UPS giving error then try charge battery keeping standby mode 14 to 24 hours.

your ups always should ac connect AC SUPPLY then only it will work properly.

check battery terminals is there any loose connections and check battery voltage. most commonly

UPS check battery integrity, when the power on, if battery fails then we may get these kind of problems.

mostly ups are used 12V 7AH to 7.4 AH battery. it's life is 2 to 3 years depend upon brand. we can increase ups battery life applying white grease to terminals and keep on always running mode 

your ups always connect AC for not discharing battery.

2  EXCESSIVE LOAD OR OVERLOAD

don't connect  dot matrix printer or laser jet printer  other multimedia spakers systems to UPS.

mostly UPS supports 300 w to 500 w. due to over load your UPS  giving errors.

should always puuggging only the PC  and mointor in the battery powered outlets.

3 relay problem, intenal smps and output mosfet damage

some UPS don't have internal SMPS for battery charging and other sections. it's had bifilar transformer it supply charging voltage. in  APC UPS used internal 14v SMPS for supply to relays and charging battery. if relay or smps fail we get error continuous beep sound and flash led.

mostly  four out put MOSFETS used in the UPS, if any one of mosfet damage or leakage

we may get errors.

trobleshooting in apc ups we have to replace IRL 3803 OUTPUT mosfets it may  leakage or damage.

UPS BEEPS SYMBOLS

SINGLE BEEP

single beep means that UPS working fine.

EVERY 10 SCONDS BEEP

it running on battery mode, you should save your work  and shutdown.

CONTINUOUSLY BEEPS

check battery, overload and output mosfets may  relay faulty.