Question on XHR100-10

[VE7HR]

I am testing out a XHR100-10 that has interesting issue. If you turn voltage control fully counterclockwise the voltage display shows 1.8V. Turning clockwise it goes to zero then continues to got to full scale. Fully CCW showing 1.8V is 0V output. Everything else approximately voltage meter on display plus 1.8V. So how does one shift that offset. I have yet to find answer in the manual. Also below 5V (6.8V) the supply makes a frying egg sound. I am hoping an expert can shed some light.

Thanks
Dave

[coromonadalix]

sv

http://www.ko4bb.com/manuals/74.57.239.193/Xantrex_XHR_Xantrex_XHR_600W_1KW_Service_Manual_TM-XR01-XN.pdf

[VE7HR]

Thanks for the link to the manual. It’s the same copy I have. I must say a few words on how it works would have been is useful.
The schematics have no hints on how it operates and does not give any details on what the various adjustment pots are for.
Dave

[coromonadalix]

is it a model you got from a seller  /  something bought used ??

on some psu   you have some rear connector  who need to be wired correctly for local use,  voltage sensing  etc ...   sometimes  they get removed  and the psu is not working well unitl you make theses connection

happened on my Kepco,  thats why i got it cheap

theses psu are advanced,  you have powerfactor correction,  power control with mosfets etc ...  3 spms sections etc ...

section 4 of the manual  show this connector,  at minimum you need to sense the output voltage

as a last resort  like i would do is find all the datasheet parts and application notes, and try to figure out   how it could work,   

in this psu  you have feedback lines  who goes between the 3 main smps sections  ....

and figuring out how they work  may or will be a pain  without trouble shooting manual  from Xantrex ...

 

[VE7HR]

I thought I replied that I got it used.
It is now fixed.
Turns out there was at least 1 cold solder joint on the board on one of the model specific resistors.

Along the way I discovered that the VI check button was displaying the correct voltage which narrowed down where to look. At 3 times under the microscope one lead did not look quite right.
So I fixed one cold solder joint. Is there more. ? Maybe. There I’d over 200 parts on the A3 board.

On to fix next item on the pile.
Thanks
Dave