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.

UPS high voltage output

Status
Not open for further replies.

malik_zohaib

Full Member level 5
Joined
Sep 1, 2010
Messages
261
Helped
36
Reputation
72
Reaction score
35
Trophy points
1,308
Location
Pakistan
Activity points
2,707
hi guys my ups is giving very high voltage about 290v with no load and 260-270v with load, i lost many mobile adapters due to this:sad:. how can i set the voltage to 230v???is there any problem in transformer???
 

MAXPAYNE

Member level 5
Joined
Feb 24, 2007
Messages
94
Helped
3
Reputation
6
Reaction score
2
Trophy points
1,288
Location
BD
Activity points
1,878
I think there is a problem in relay or relay driving transistor, which is used for AVR (automatic voltage regulator) in an UPS.
 

malik_zohaib

Full Member level 5
Joined
Sep 1, 2010
Messages
261
Helped
36
Reputation
72
Reaction score
35
Trophy points
1,308
Location
Pakistan
Activity points
2,707
can you explain this? how can relay control the voltage or regulate it????
 

MAXPAYNE

Member level 5
Joined
Feb 24, 2007
Messages
94
Helped
3
Reputation
6
Reaction score
2
Trophy points
1,288
Location
BD
Activity points
1,878
In a UPS AVR, there are several tapping in the secondary. these tapped point voltage connects in phase with the primary and acts as an auto-transformer i.e. total output voltage is greater than input voltage. if secondary is out of phase with primary total output voltage reduces. relay is used for changing tha tapped connection. this way voltage is regulated in an UPS.
 

malik_zohaib

Full Member level 5
Joined
Sep 1, 2010
Messages
261
Helped
36
Reputation
72
Reaction score
35
Trophy points
1,308
Location
Pakistan
Activity points
2,707
this mechanism is used in stabilizer not in ups!!!. triangular and sine waves are used to generate the appropriate pwm in ups.
 

MAXPAYNE

Member level 5
Joined
Feb 24, 2007
Messages
94
Helped
3
Reputation
6
Reaction score
2
Trophy points
1,288
Location
BD
Activity points
1,878
in iron core transformer based UPS, this mechanism is used !
 

masterleous

Advanced Member level 4
Joined
Feb 1, 2008
Messages
112
Helped
29
Reputation
58
Reaction score
26
Trophy points
1,308
Location
Pakistan
Activity points
1,993
can you explain this? how can relay control the voltage or regulate it????

Is this a first time that you had checked the output voltage of this UPS? or had checked before? I think you are using a locally made UPS. If YES than don't worry, its normal. The voltage goes lower and so on upon increasing LOAD.
 

murali_dece

Member level 5
Joined
Jul 21, 2004
Messages
83
Helped
26
Reputation
52
Reaction score
25
Trophy points
1,298
Location
india
Activity points
549
first you wright down all the ic numbers in your ups and search for data sheets to find pulse width modulator used in your UPS. by modifying feedback loop/network you can reduce output voltage slightly.
 

tpetar

Advanced Member level 5
Joined
Sep 27, 2010
Messages
6,427
Helped
1,713
Reputation
3,456
Reaction score
1,678
Trophy points
1,393
Location
Pancevo-Belgrade, Serbia
Activity points
37,374
Voltage in UPS is regulated over transformators windings. You should check control circuit.


Example of voltage correction device, not UPS but principe of voltage regulation :

kor..jpg

220V 210V 200V 190V 180V

Each relay is connected with adequate transformator windigs.
 

malik_zohaib

Full Member level 5
Joined
Sep 1, 2010
Messages
261
Helped
36
Reputation
72
Reaction score
35
Trophy points
1,308
Location
Pakistan
Activity points
2,707
Is this a first time that you had checked the output voltage of this UPS? or had checked before? I think you are using a locally made UPS. If YES than don't worry, its normal. The voltage goes lower and so on upon increasing LOAD.
yes its locally made and i checked it before. but now its damaging appliances like fan, mobile charger, and adopters.
 

tpetar

Advanced Member level 5
Joined
Sep 27, 2010
Messages
6,427
Helped
1,713
Reputation
3,456
Reaction score
1,678
Trophy points
1,393
Location
Pancevo-Belgrade, Serbia
Activity points
37,374
Localy made or not this is wrong situation, and you will continue destroying your devices. UPS must have appropriate voltage on output 220V/110V. Maybe this is bad design or some "expert" made that, or have some failed parts inside.
 

malik_zohaib

Full Member level 5
Joined
Sep 1, 2010
Messages
261
Helped
36
Reputation
72
Reaction score
35
Trophy points
1,308
Location
Pakistan
Activity points
2,707
Localy made or not this is wrong situation, and you will continue destroying your devices. UPS must have appropriate voltage on output 220V/110V. Maybe this is bad design or some "expert" made that, or have some failed parts inside.

so what i do? how do i locate the faults?
 

tpetar

Advanced Member level 5
Joined
Sep 27, 2010
Messages
6,427
Helped
1,713
Reputation
3,456
Reaction score
1,678
Trophy points
1,393
Location
Pancevo-Belgrade, Serbia
Activity points
37,374
Tell us whole story? Is this from begining? Did ever ups running ok with voltage before ?

---------- Post added at 13:45 ---------- Previous post was at 13:45 ----------

Send pictures of device and circuit if you have.
 

malik_zohaib

Full Member level 5
Joined
Sep 1, 2010
Messages
261
Helped
36
Reputation
72
Reaction score
35
Trophy points
1,308
Location
Pakistan
Activity points
2,707
it was working fine before. during thunder night it just stop working (static charge i guess!!) and when i checked the main board the relay (they called it soft starter!!!) is damaged. i had to take it to my supplier, and he replaced the relay. since then its not working properly. IMAG0016.jpgIMAG0017.jpg
 

mtwieg

Advanced Member level 5
Joined
Jan 20, 2011
Messages
3,593
Helped
1,267
Reputation
2,540
Reaction score
1,264
Trophy points
1,393
Activity points
27,038
Without knowing the operating principle of the UPS it's hard to say. Is it a PWM inverter, multilevel converter, simple square wave inverter, etc...
 

tpetar

Advanced Member level 5
Joined
Sep 27, 2010
Messages
6,427
Helped
1,713
Reputation
3,456
Reaction score
1,678
Trophy points
1,393
Location
Pancevo-Belgrade, Serbia
Activity points
37,374
Yes this is relay. This is small power ups, for what you using this?

What he change of this parts ? Did you return board to service again ?
 
Last edited:

malik_zohaib

Full Member level 5
Joined
Sep 1, 2010
Messages
261
Helped
36
Reputation
72
Reaction score
35
Trophy points
1,308
Location
Pakistan
Activity points
2,707
i dont know its purpose. he just changed the relay. i am using the same board.
 

malik_zohaib

Full Member level 5
Joined
Sep 1, 2010
Messages
261
Helped
36
Reputation
72
Reaction score
35
Trophy points
1,308
Location
Pakistan
Activity points
2,707
i am using to power fan, energy saver, mobile charger etc. also let me tell you one thing more: my ups is 1200VA, and its just the main board; the inverter is fitted into the casing.
 

tpetar

Advanced Member level 5
Joined
Sep 27, 2010
Messages
6,427
Helped
1,713
Reputation
3,456
Reaction score
1,678
Trophy points
1,393
Location
Pancevo-Belgrade, Serbia
Activity points
37,374
Best is to send this to manufacturer service. Its hard to tell anything from this, except if we have Baba Vanga capabilities.
 

Status
Not open for further replies.

Similar threads

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Top