dead paper shredder with crap caps

Collapse
X
 
  • Time
  • Show
Clear All
new posts
  • cyclones
    Senior Member
    • Feb 2010
    • 69

    #1

    dead paper shredder with crap caps

    I am trying to troubleshoot a dead paper shredder. It is a rather beefy looking thing from Staples. Big motor. It will not power up. None of the LEDs on the panel come on. I checked the simple things like power cord and fuse and no problems there.

    Looking at the main board, it is a super cheap design. It has no transformer, just resistors, a few electrolytic caps (zckj or something like that -- a known bad brand) and four diodes. Then there are a couple of relays to control the motor. The board also has an 8-bit Samsung microcontroller on it and a couple of polyester or ceramic capacitors. That's pretty much it. I was going to start by replacing the 5 electrolytic capacitors with high quality ones and see what happens since it's only a couple of $ to do that.

    Any other ideas on what to check? Thanks!!
  • retiredcaps
    Badcaps Legend
    • Apr 2010
    • 9271

    #2
    Re: dead paper shredder with crap caps

    Originally posted by cyclones
    Any other ideas on what to check? Thanks!!
    Can you post a picture so we can suggest test points?
    --- begin sig file ---

    If you are new to this forum, we can help a lot more if you please post clear focused pictures (max resolution 2000x2000 and 2MB) of your boards using the manage attachments button so they are hosted here. Information and picture clarity compositions should look like this post.

    We respectfully ask that you make some time and effort to read some of the guides available for basic troubleshooting. After you have read through them, then ask clarification questions or report your findings.

    Please do not post inline and offsite as they slow down the loading of pages.

    --- end sig file ---

    Comment

    • cyclones
      Senior Member
      • Feb 2010
      • 69

      #3
      Re: dead paper shredder with crap caps

      Here is a photo of the board that I took. I did replace the crap caps with good ones but still the board appears dead. There is definitely continuity from the plug to the board.

      Last edited by cyclones; 05-13-2012, 12:31 PM.

      Comment

      • digge
        Badcaps Veteran
        • Apr 2006
        • 296

        #4
        Re: dead paper shredder with crap caps

        DZ902-DZ905 is probably diodes working as a rectifier, make sure those are ok. Would be easier to figure it out of you had a photo of the back of the board as well. I cant read the numbers on the small IC but guessing its a voltage regulator? If it is, find a datasheet and measure the output pin and see what you get.

        Im also assuming the relays are for forward and backwards drive of the motor, they are not used for power on?

        Comment

        • Scenic
          o.O
          • Sep 2007
          • 2642
          • Germany

          #5
          Re: dead paper shredder with crap caps

          Originally posted by digge
          I cant read the numbers on the small IC but guessing its a voltage regulator?
          The small 8pin IC says "ATMEL 24C___" (unreadable), so it's most likely an EEPROM.

          Opening the image in a new tab shows it in it's full size, rather than the stupid javascript resizing mess when you click on it, which will be larger, but still not the original size.

          Comment

          • multimeter
            Badcaps Veteran
            • Jan 2011
            • 739
            • united kingdom

            #6
            Re: dead paper shredder with crap caps

            i may be wrong but those lytics look like g-luxon caps?,if they are they are general purpose ones,panasonic fc series is a good near match replacement
            fixed so far...376 lg lcd tv's,24 onn tv;s,24 panasonic lcd,16 jvc lcd,12 marshall jcm800 amps,refurb of various disco equipment lighting,old style disco decks ,and a flymo!

            ----------------------------------------------
            please let us know if everything works ok if your tv gets fixed, as it will be and aid for anyone else having the same problem and wishing to fix it.it would save people clogging up this site with topics that are duplicated,and can be found easily using the search function.,and taking up valuable space.enjoy your fixed tv!,hopefully!

            Comment

            • cyclones
              Senior Member
              • Feb 2010
              • 69

              #7
              Re: dead paper shredder with crap caps

              Yes, I thought the diodes were probably performing the rectifier function. I tried getting continuity across DZ902 and can't seem to get anything either direction. The caps in the photo are new Panasonic.

              Comment

              • mariushm
                Badcaps Legend
                • May 2011
                • 3799

                #8
                Re: dead paper shredder with crap caps

                It's a Zener diode, most likely.. a bit harder to test.

                Comment

                • Th3_uN1Qu3
                  Believe in
                  • Jul 2010
                  • 6031
                  • Romania

                  #9
                  Re: dead paper shredder with crap caps

                  A zener is still going to behave like a normal diode in forward mode, so you should have been getting a reading in one direction. It could have failed open.
                  Originally posted by PeteS in CA
                  Remember that by the time consequences of a short-sighted decision are experienced, the idiot who made the bad decision may have already been promoted or moved on to a better job at another company.
                  A working TV? How boring!

                  Comment

                  • budm
                    Badcaps Legend
                    • Feb 2010
                    • 40746
                    • USA

                    #10
                    Re: dead paper shredder with crap caps

                    It has current source power supply setup (Capacitive Transformerless Power Supply) using Xc of the capacitor to drop the voltage instead of using resistor which the resistor will get hot due to power dissipation) to put out 24Vdc to power the relays and there are resistors/Zener Diode to rugulated the voltage to run the IC's.
                    Need good pictures of the backside of the board.
                    If you trace out the connection on one leg of the fuse, it should go to low Ohm resistor, another end of the resistor will be connected to one leg of that large brown cap, the output of the brown cap should be connected to the rectifier circuits and Zener Diode to regulated the voltage.
                    To check Zener voltage, all you need is variable DC power supply and 1K resistor (to limit the current) in series with the Zener, and DMM.
                    Plus output of the power supply to resistor, output side of the resistor to the Cathode of the Zener, Negative to the Anode. Put the DC meter across the Diode, turn up the power supply output until it does not go up anymore even you keep putting out more voltage, what you see on the meter will be the Zener voltage of the Diode.
                    By the way, please also post new direct front view of the board so we can see all the parts.
                    Attached Files
                    Last edited by budm; 05-13-2012, 10:16 PM.
                    Never stop learning
                    Basic LCD TV and Monitor troubleshooting guides.
                    http://www.badcaps.net/forum/showthr...956#post305956

                    Voltage Regulator (LDO) testing:
                    http://www.badcaps.net/forum/showthr...999#post300999

                    Inverter testing using old CFL:
                    http://www.badcaps.net/forum/showthr...er+testing+cfl

                    Tear down pictures : Hit the ">" Show Albums and stories" on the left side
                    http://s807.photobucket.com/user/budm/library/

                    TV Factory reset codes listing:
                    http://www.badcaps.net/forum/showthread.php?t=24809

                    Comment

                    • cyclones
                      Senior Member
                      • Feb 2010
                      • 69

                      #11
                      Re: dead paper shredder with crap caps

                      Here is a photo of the back side of the board. What spec of zener diodes will I need, assuming the diode(s) is/are the problem?

                      Comment

                      • budm
                        Badcaps Legend
                        • Feb 2010
                        • 40746
                        • USA

                        #12
                        Re: dead paper shredder with crap caps

                        Can you please do straight shot of the board both top and bottom sides instead of tilted pictures? Also use the attachment to post the pictures. It is hard to trace the copper lines on the board when pictures are not clean and clear. We are doing long distant troubleshooting without having the board in front of us, so good pictures are very important.
                        Never stop learning
                        Basic LCD TV and Monitor troubleshooting guides.
                        http://www.badcaps.net/forum/showthr...956#post305956

                        Voltage Regulator (LDO) testing:
                        http://www.badcaps.net/forum/showthr...999#post300999

                        Inverter testing using old CFL:
                        http://www.badcaps.net/forum/showthr...er+testing+cfl

                        Tear down pictures : Hit the ">" Show Albums and stories" on the left side
                        http://s807.photobucket.com/user/budm/library/

                        TV Factory reset codes listing:
                        http://www.badcaps.net/forum/showthread.php?t=24809

                        Comment

                        • cyclones
                          Senior Member
                          • Feb 2010
                          • 69

                          #13
                          Re: dead paper shredder with crap caps

                          I will try to get better shots of the front and back of the board. In the meantime, I have checked the DZ on the front of the board and they all measure about 600-700 ohms in the forward direction except for DZ901, which was much lower, I think around 20.. it looks different than the other diodes. Previously I was having trouble because there appears to be a thin coating of something on the back of the board, but touching it with the soldering iron solves that problem. None of those diodes seem to be open. I also checked surface mount diodes on the back of the board and all have about 600-700 ohms resistance.

                          Also, could someone tell me what the blue component labelled RZ901 is and what it's for, and also the yellow block capacitors.

                          I will be back later this evening with better photos. Thanks.

                          Comment

                          • cyclones
                            Senior Member
                            • Feb 2010
                            • 69

                            #14
                            Re: dead paper shredder with crap caps

                            I updated the photos.

                            Comment

                            • budm
                              Badcaps Legend
                              • Feb 2010
                              • 40746
                              • USA

                              #15
                              Re: dead paper shredder with crap caps

                              RZ901 is more likely to be surge protection device if the line voltage goes over 140Vac which will cause the fuse to blow. The yellow cap is connected across the AC line for noise filter so it will reduce the noise from the motor from injecting the noise back into the AC line.
                              Did you have a chance to check the DC voltage on the electrolytic caps yet, be careful since you will be working on the line voltage, do not touch any traces with your hands or body.
                              Never stop learning
                              Basic LCD TV and Monitor troubleshooting guides.
                              http://www.badcaps.net/forum/showthr...956#post305956

                              Voltage Regulator (LDO) testing:
                              http://www.badcaps.net/forum/showthr...999#post300999

                              Inverter testing using old CFL:
                              http://www.badcaps.net/forum/showthr...er+testing+cfl

                              Tear down pictures : Hit the ">" Show Albums and stories" on the left side
                              http://s807.photobucket.com/user/budm/library/

                              TV Factory reset codes listing:
                              http://www.badcaps.net/forum/showthread.php?t=24809

                              Comment

                              • cyclones
                                Senior Member
                                • Feb 2010
                                • 69

                                #16
                                Re: dead paper shredder with crap caps

                                I have not checked voltage on the electrolytic caps. I'm not too keen on working on this "live" without an isolation transformer or some other safety equipment. The electrolytics should be good as they are new panasonics. I did check out all the diodes and the reddish-brown film capacitor -- the monster one -- and all can pass current. Everything was looking ok, but on the back of the board, there are some surface mount transistors. They are all labelled J3Y or 2TY. These are in the lower right of the photo of the back of the board. The top pair seem to check out, the middle pair seem to check out, but the bottom pair I cannot get any continuity between any two leads in any direction. I even touched the solder joints with the iron to try to burn off any coating. Still nothing. Not sure what the function of these is. I tried to trace the lines and found it appears to go to the paper switch -- on the front, there are three leads labelled "paper 2" which go to a switch mechanism that detects paper being placed in the shredder.

                                Comment

                                • budm
                                  Badcaps Legend
                                  • Feb 2010
                                  • 40746
                                  • USA

                                  #17
                                  Re: dead paper shredder with crap caps

                                  That large brown cap is part of drop down the power supply (it uses Xc of the cap to drop down the voltage), I can see a couple Diodes connected to the out put side of that cap, it should go to electrolytic cap. I could not trace the board too well using your pictures because I need to look at the component side , then the soldered side back an forth to see how components are connected together.
                                  Never stop learning
                                  Basic LCD TV and Monitor troubleshooting guides.
                                  http://www.badcaps.net/forum/showthr...956#post305956

                                  Voltage Regulator (LDO) testing:
                                  http://www.badcaps.net/forum/showthr...999#post300999

                                  Inverter testing using old CFL:
                                  http://www.badcaps.net/forum/showthr...er+testing+cfl

                                  Tear down pictures : Hit the ">" Show Albums and stories" on the left side
                                  http://s807.photobucket.com/user/budm/library/

                                  TV Factory reset codes listing:
                                  http://www.badcaps.net/forum/showthread.php?t=24809

                                  Comment

                                  Related Topics

                                  Collapse

                                  • CapSnap123
                                    Sensor on Aurora AS1018CD paper shredder doesn't work
                                    by CapSnap123
                                    I'm getting frustrated troubleshooting a paper shredder. The way the shredder normally works is when you turn the power on, nothing happens until you insert a piece of paper. There is an IR shredder in the shredder and inserting the paper breaks the beam and starts the shredder motor. But now the motor runs constantly, even when no paper is inserted. I've replaced the photodiode and the IR emitter. Also the relay makes a nice clicking sound so I assume it is working too. I don't know what else to check. Here's a photo of the circuit board. The red and black wires marked IR - go to the...
                                    04-20-2024, 03:57 PM
                                  • momaka
                                    Seasonic B12 BC-550 – barely 2 years old and with BAD CAPS already!
                                    by momaka
                                    I know I've been a little scarce lately (like the last 2-3 years), but I'm still here and still doing my thing with fixing PSUs.

                                    For today's considerations, I have a Seasonic B12 BC-550 [A551bcafh] 550 Watt ATX power supply for you (click on links for full size images).

                                    https://www.badcaps.net/filedata/fetch?id=3591771


                                    https://www.badcaps.net/filedata/fetch?id=3591772

                                    It's a modern ATX unit with fixed (non-modular) cables and an 80-plus bronze certificate. Here's the label:

                                    https://www.badcaps.net/filedata/fetch?id=359177...
                                    03-12-2025, 03:42 PM
                                  • esqmooo
                                    HP Elitebook 845 G8 dead, only caps lock flashing 7 times. Charging light always on
                                    by esqmooo
                                    Hello everyone.

                                    This is my development machine. I've been using it since two years and half without any problem except sometimes it wouldn't wake up from sleep.
                                    Lately the issue became more frequent and powering it up would take few seconds to show the POST screen.
                                    Then the computer refuses to power on at all. Now only the caps lock button flashes 7 times then stops. The charging light is always on whenever a power source is connected (battery or charger).
                                    I tried long pressing on the power button, after several seconds it would go off then when the button is released...
                                    03-11-2025, 03:57 PM
                                  • captain150
                                    Help with switching power supply caps
                                    by captain150
                                    I'm trying to repair two old VCRs, they both have bad caps. One has leaky ones, the other would barely run until I subbed in some caps from another power supply I had laying around (though they are the wrong values). This vcr works for an hour or two, but then the power supply starts whining and the picture gets lines in it. I didn't replace all the secondary caps, so another voltage might still be problematic, or the values I used are too far off.
                                    I've been on mouser and digikey but the options are a bit overwhelming. I just need some new ones that will work. They don't need to be top quality,...
                                    03-16-2025, 07:34 PM
                                  • Foetuss
                                    Gigabyte GA-6OXT :: caps question
                                    by Foetuss
                                    Good evening

                                    I recently aquired a rev 1.1 Gigabyte 60XT, and was suprised of the amount of leaking caps for a motherboard of the P3 era. Especially the way the 330µf caps seems like the housing discolored even.
                                    Now, there are some 3300µF 6.3V KZG series around the CPU. Would it be OK to replace them with something like EEUFR1A332 ? (Panasonic FR 3300µF 10V). Or was this board designed around very low ESR caps?

                                    But I was also suprised about the bigger boys, which are 330µF 25V.
                                    Could it be they used 25V caps because they were cheaper / available at that time?...
                                    02-11-2025, 12:22 PM
                                  • Loading...
                                  • No more items.
                                  Working...