Ups apc su3000rm3u resistor wrong

It is not entirely risk free to change the batteries.
If you saw a spark at the connection of the new batteries, UPS may have been damaged.
Next time, preload with a 100 Ohm resistor in series with the battery to limit the inrush current!

Replace the parts with the original ones, a .5 ohm difference on a resistor on the video circuits will cause the unit not to work correctly.

How did you hook it up? IT takes a 470 ohm resistor

R37 10 ohm 1/2 Watt

R38 2 ohm 1/4 watt

also change d12 1n4148

check the fan in the back .... try to replace if damaged

Hi Petkov,

It seems that Schneider / APC has a remedy for this on their forum:

http://forums.apc.com/message/35667

Reply or call if you need more assistance with this -- 407.380.9200

I Bought two RBC32's and had to hook them up to the connector and did it wrong on the first try. Make sure you connect the yellow to the Red terminal on one battery and the Black on the other, then connet the remaining red to red on one and black to black to the other. Once I did that and plugged it back in everything worked fine.

When thosse resistors (precharrging of main input filters) burn up there is major damage. The IGBT's are usually gone... replace with APT28GA60BD15... the switching regulator IR2153 is gone... one or more of the 2SA1020-Y and the 2SC2655-Y gate drivers are gone. One or both of the DL4148 speedup diodes for the IGBT gate drives will be gone. The Wirewound ceramic resistors either 10 or 22 ohm 10 watt radials... Use:
http://www.mouser.com/ProductDetail/Ohmite/TWW10J20RE/?qs=GcOFt9%2fAxQHny%252b35G6iehQ%3d%3d
This is 20 ohms, however Behringer uses from 10 to 22 ohms in these units... 20 works fine as does 10 ohms. If you have toruble getting schematic let me know.

It is recommended to use the same value due to the function of the resistors and their values.
A lower value will let the current flow a bit faster and the higher value will slow it down according to their design.
Try installing the same value of 220 ohms.
Hope this helps.

That would be verry difficult to find. A service diagram of this model is imposible to be found, at least over the internet. However here are some tips you may find usefull. If you have acces to a multimeter or at least a current-voltage measuring device, try to turn on the laptop and measure the voltage on those pins where the resistor is missing. If you find something smaller then 10 volts you can try the following method.
Buy a 1 mega ohm resistor along with other smaller values like 100kilo ohm, 10kilo ohm, 1 kilo ohm, 100ohms, 10 ohms. These resistors don't need to be smd tipe, regular ones are good at least for this testing stage as long as you can solder them on the motherboard. Begin by using the larger values (1 mega ohm) and check to see if the problem is solved or something is different. Then decrease step by step checking each time how the problem evolves. When you reach to 1 kilo ohm, don't solder the resistence like before, instead mount an amper-meter in series (not parralel !!! ) with the resistor. Check to see how much current is passing through the resistor. If you find more then 100mA stop here, because by following this metod down to smaller values of that resistor you may damage the board if the current exceeds certain levels.
Try this simple tests and please notify my of the results. You may ask further questions if you need more details on this matter.