Continue to Site

Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

Register Log in

Troubleshooting the UPS

Status
Not open for further replies.
S

simon_12

Junior Member level 3
Joined
Sep 7, 2009
Messages
28
Helped
1
Reputation
2
Reaction score
1
Trophy points
1,283
Activity points
1,476
Hi all

The output voltage of my UPS is approx 300 volts. I have also checked the transistors, they are working properly. When the battery is charging , through main supply, the output voltage is upto the normal value that is 220 volts, but as soon as the main supply fails and the UPS starts , the output voltage becomes 300 volts. Can anyone pls tell me what is the PROBLEM

regards
 

actually your ups is square wave and every square wave ups gives 300 output volt
& more without load when you on the load it goes down so you need to add a circuit of pwm which can fix your required voltage.
 

But , when i previously checked the output voltage of ups , it was around 220 volt on load. There must be some problem with the output voltage of UPS now, because each time when the ups comes on load , the FUSE blows.

Regards
 

Hi simon,
Check the feedback section of your inverter. Check any optocouplers and associated resistors and potentiometer. Check the connection of these parts to the oscillator and use a multi-meter to check the output duty cycle and frequency from the PWM chip (SG3524, SG3525, etc.)

Hope this helps.
Tahmid.
 

hi
sure there will be problem with the PWM circuitry
in PWM control IC, there are 2 options one for fixed reference(normally 2.5V) and another is varying output voltage variation pot(more than 2.5V). u adjust that pot such that difference between reference and output reference is minimum.at particular poin u will acheive what ever output volotage u want.
 

Hi,
Adjust the pot and see if you can vary the output voltage. If you can, good, then set the output to 220V. If you can't you might need to replace some part, most likely the optocoupler (if the circuit employs an optocoupler) or the current limiting resistor at the input of the optocoupler.

Hope this helps.
Tahmid.
 

Status
Not open for further replies.

Similar threads

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Back
Top