Absolute beginner requesting help identifying component - Page 1
Forum section: electronics / beginners

author: tebbybabes
author_rank: Contributor
timestamp: December 24, 2019, 03:37:49 am
content: Hello, my name is Steven and I've just come across your forum. Took the chance to register so I might get the chance to further my knowledge.Quick backstory is I have a ceiling fan that is slower than molasses and I at least know enough that it's most likely a capacitor problem. The fan company says that the problem is an easy fix and that I just need to replace the controller module and it will be right as rain. Trouble is, the electronic module, while user replaceable, is also $100, while the fan itself is just $200. I figured I would try to have a look at it and maybe learn something new.Which takes me to my current query.I was hoping I could ask help in identifying this particular component in the photo. It's the one that looks like dumbells? I know the big yellow ones are capacitors and I thought they would be the one needing the replacing, but these ones look a bit dogdy.Thanks in advance and if I'm barking up the wrong tree, apologies.

author: xrunner
author_rank: Super Contributor
timestamp: December 24, 2019, 03:40:34 am
content: They are inductors with a heat shrink over the windings. Usually labelled with an "L" such as you see on the PCB.

author: Ian.M
author_rank: Super Contributor
timestamp: December 24, 2019, 03:50:44 am
content: .... and they look absolutely normal, with no signs of overheating or other issues.

author: tebbybabes
author_rank: Contributor
timestamp: December 24, 2019, 05:01:07 am
content: Thanks heaps, folks. That was even faster than I was hoping!and @xrunner, I have now noticed the "L" that you mentioned. Thanks.In this case, I will now see if I can learn how to test capacitors to find out which one needs replacing. Can't say that I'm super confident as the last time I soldered circuits was 30 years ago and I remember I did a piss-poor job of it.

author: andy3055
author_rank: Super Contributor
timestamp: December 24, 2019, 06:19:22 am
content: In the ceiling fan there should be another capacitor at the top, inside the canopy. That could be the most likely faulty part.

author: Siwastaja
author_rank: Super Contributor
timestamp: December 24, 2019, 06:58:00 am
content: And those yellow capacitors are likely OK, too. Swapping parts randomly tends to end up costly.Indeed, if there is a "run" capacitor at the motor, it's a more probable cause, because it can run hot next to the motor.

author: tebbybabes
author_rank: Contributor
timestamp: December 24, 2019, 07:28:32 am
content: Thanks for the replies and the very helpful input.The only reason I thought it might be one of these things was because the tech support person on the line sounded extremely confident that replacing this module was the definitive fix. It led me to believe that any "run" capacitor would be in it. I have another photo of it that some of you folks might find more representative. This "control module" is located up top in the canopy. It was conveniently happened to be a user replaceable part.Anyway, I was initially planning to remove the caps one by one and check them with a multimeter to determine which one needed replacing?

author: taydin
author_rank: Frequent Contributor
timestamp: December 24, 2019, 09:02:25 am
content: You can only measure the capacitance value of a known working capacitor when using a multimeter. But there are two types of faults that will cause little or not change in the capacitance, but still will prevent the cap from working properly:High ESR: The capacitance value might be measure a little off, so it will look fine, but the cap will not be able to do its job. Standard multimeters lack ESR measurement. You need an LCR meter to measure ESR.Insulation breakdown at operating voltage: This is a rare problem, but when it happens, the capacitor will measure fine even with an LCR meter. But when normal operating voltage is applied to it, its insulation breaks down partially or completely and the capacitor won't do its job at all. The only way to properly test the cap is to apply rated voltage and observe leakage current (not easy, especially when voltages are high and typical leakage is low).It is much easier and cheaper to just replace caps that are likely to fail.

author: andy3055
author_rank: Super Contributor
timestamp: December 25, 2019, 01:06:08 am
content: By the way, taking another look at the last picture you posted, I wonder if that one capacitor sitting alone to the left is the run capacitor I was referring to. If there is no other capacitor lying alone inside the canopy, there is a good chance they mounted it on this board. Usually they are in the order of 2uF or so. The other 3 caps must be for speed control and this one cap is acting as the run cap. Just a thought.

author: Gregg
author_rank: Super Contributor
timestamp: December 25, 2019, 02:15:38 am
content: Also check the electrolytic caps like C2, C13 and the other two similar ones. In a hot environment like a ceiling fan, they can degrade and cause the control circuitry to malfunction. These usually show some sign of leaking or bulging, but not always.The oval yellow caps are not likely a problem, but anything can happen.

author: Jwillis
author_rank: Super Contributor
timestamp: December 25, 2019, 02:16:01 am
content: BRT2-SS-212D PCB relays 12 Vdc 8 AThe three caps with inductors are LC tank circuits . They oscillate at different frequencies for different motor speeds. The motor is likely a Shaded-pole synchronous motor.Change the frequency change the speed of the motor. The triacs switch between each tank circuit.The Relay may be for forward reverse difficult to tell without a board schematic or picture of the traces. Their as a chip on board .What is it.

author: ArthurDent
author_rank: Super Contributor
timestamp: December 25, 2019, 03:42:12 am
content: You've got some good information here. I'm also assuming this is a remote control 3-speed fan which accounts for 3 identical inductor/triac/capacitor circuits on the board like the one I circled. I'd guess that the single big yellow cap is the run cap as previously stated and that is the problem. The capacitance has probably decreased greatly and all speeds are very slow. Checking the value should verify this if it is the problem.

author: tebbybabes
author_rank: Contributor
timestamp: December 25, 2019, 11:12:30 am
content: Quote from: taydin on December 24, 2019, 09:02:25 amThank you for taking the time to explain so much. I am obviously way way over my head, but am more than willing to listen. I like how the last bit is quite practical from an expediency standpoint!Quote from: andy3055 on December 25, 2019, 01:06:08 amThanks. You and @ArthurDent are thinking along the same lines. I don't yet know what spec is the lone cap but I can read enough of the other three to say that they are 2.0uF, 1.0mfd, 2.5uFQuote from: Jwillis on December 25, 2019, 02:16:01 amI'll take as good a picture as I can, but can say that it has LNK302PN printed on it.Quote from: ArthurDent on December 25, 2019, 03:42:12 amProduct documentation states that it is a 7 speed remote controlled ceiling fan. And yes, all speeds are slow as molasses in winter.As soon as get my ducks in a row and remove that big lone cap, I will report in.

author: ArthurDent
author_rank: Super Contributor
timestamp: December 25, 2019, 02:40:01 pm
content: When I posted I was thinking of each of the three circuits used separately but with 3 circuits you can have 3! (3 factorial) or 3x2x1 combinations (plus all circuits off) to get 7 combinations so what you say about it being a 7 speed fan makes sense. The triacs are just used as switches to switch all the combinations of the 3 circuits on or off. Below is a photo of a similar circuit board I found on line that does about the same thing. They used SCRs instead of triacs but the effect is the same. You can see that the capacitors are in about the same ratio as on your circuit board and the difference might be they used SCRs instead of triacs.The IC on the board with some of the other small parts form a really neat AC-DC buck converter and is probably used to get 12VDC for the relay coil and perhaps other parts of the controller.

author: amyk
author_rank: Super Contributor
timestamp: December 26, 2019, 10:38:37 pm
content: Quote from: tebbybabes on December 25, 2019, 11:12:30 amAre you sure it's not the bearings that need oiling?

author: andy3055
author_rank: Super Contributor
timestamp: December 27, 2019, 02:24:20 am
content: I don't think it is the bearing. That can be easily checked though. If you just spin the fan without power, it should spin for a few revolutions. If not, then one could suspect the bearing.The big cap should have the ratings on the bottom that is towards the board. Just de-solder one side and see what is underneath.

author: tebbybabes
author_rank: Contributor
timestamp: December 28, 2019, 11:52:32 am
content: Quote from: ArthurDent on December 25, 2019, 02:40:01 pmThanks for the photo. I will admit, the first time I read your reply, I missed it.@amykIn this case I can definitely report that it isn't the bearings because the damn thing spins very very freely.@andy3055Will do, as soon as I get to the non-holiday period and I'm no longer running around like a chicken.Happy and Blessed holidays everyone!

author: tebbybabes
author_rank: Contributor
timestamp: December 30, 2019, 07:46:16 am
content: Assumed "run" capacitor removed. Have not been able to properly test yet because it turns out I don't have a multimeter with capacitance.Now hunting around where to order this part.I've got an advance question, how do I determine polarity for the replacement cap? I took a photo of how it's oriented on the original parts but have failed to find any identifying marks.And finally an aside, I think my el cheapo solder sucker wasn't working very well... It took ages to remove enough solder to finally disengage the cap and even when I did, there was still heaps of solder left. Do I need to hunt for a wick instead to get it cleaned up better?

author: Zero999
author_rank: Super Contributor
timestamp: December 30, 2019, 09:44:37 am
content: Those yellow capacitors are non-polarised, which means they can be connected either way round.You can try desolder wick and extra flux might also help.

author: tebbybabes
author_rank: Contributor
timestamp: December 30, 2019, 10:39:42 am
content: Quote from: Zero999 on December 30, 2019, 09:44:37 amMuch obliged.Will hunt around for the wick and the capacitor then.

author: andy3055
author_rank: Super Contributor
timestamp: December 30, 2019, 11:20:23 am
content: Did you also check inside the canopy if there is another cap? If not, try changing the cap that you lifted.

author: tebbybabes
author_rank: Contributor
timestamp: January 02, 2020, 12:20:51 am
content: Quote from: andy3055 on December 30, 2019, 11:20:23 amThanks. Confirmed that there are no other capacitors, or electronics for that matter, in the canopy.

author: tebbybabes
author_rank: Contributor
timestamp: January 02, 2020, 12:32:23 am
content: I've come up against a snag. After hunting around my local area, it appears that sourcing caps like these are harder than I thought. I also went online and didn't find many options. I often found the same specs listed under "motor start/run motor" categories, however they were always shaped like the rectangular plastic boxes. They're very reasonably priced too.The only ones that appeared to have a similar shape to the one I lifted are caps that have been described as either "audio" or "snubber" and their pricing is several orders of magnitude higher. I have an impression that these specialised caps aren't actually what I need, but decided to ask for advice.Finally, my google-fu must be lacking, but can anyone point me in the direction of where best to source this sort of thing in Oz? Doesn't matter if online or in meatspace.Thanks again.

author: Jwillis
author_rank: Super Contributor
timestamp: January 02, 2020, 01:44:34 am
content: Quote from: tebbybabes on January 02, 2020, 12:32:23 amCBB20 Motor Run Capacitor axial lead ?uF

author: tebbybabes
author_rank: Contributor
timestamp: January 02, 2020, 01:53:18 am
content: Quote from: Jwillis on January 02, 2020, 01:44:34 amIt says 1.5uf 800VDC ± 10%. From what I can gather, I would just need to sorta extend the legs on the rectangular housed cap that I found. They seem to have a bit shorter total length that the spot on the PCB.

author: andy3055
author_rank: Super Contributor
timestamp: January 02, 2020, 02:12:24 am
content: You can find them on eBay Australia. What you are looking for is ceiling fan capacitors.https://www.ebay.com.au/sch/i.html?_from=R40&_trksid=m570.l1313&_nkw=ceiling+fan+capapcitor&_sacat=0The original cap is rated at 800 volts - probably DC. 450 volt rated cap is more than enough as your AC line voltage is only 230/240 V (?).

author: Jwillis
author_rank: Super Contributor
timestamp: January 02, 2020, 02:22:53 am
content: Doesn't seem to be many axial caps in that range unless you go to digikey or mouser. examplehttps://www.digikey.com.au/products/en/capacitors/film-capacitors/62?k=&pkeyword=&sv=0&pv1293=290984&sf=1&FV=16%7C317190%2C-8%7C62%2Cmu1.5%C2%B5F%7C2049&quantity=&ColumnSort=0&page=1&pageSize=25

author: andy3055
author_rank: Super Contributor
timestamp: January 02, 2020, 02:32:50 am
content: Quote from: Jwillis on January 02, 2020, 02:22:53 amGood find!https://www.digikey.com.au/product-detail/en/kemet/C4GAMUD4150AA1J/399-13880-ND/6558708

author: calzap
author_rank: Frequent Contributor
timestamp: January 02, 2020, 06:24:16 pm
content: In the U.S., many ceiling fans have a current-limiting module that is separate from the motor speed control module. Its purpose is to prevent high wattage light bulbs from being used in the associated bulb sockets ... government-mandated energy conservation, but may have a safety function as well. It's usually a small plastic box tucked away in the fan housing.I've seen several of these fail, and usually they cause strange behavior in the lights (dimming, flickering, pulsing, etc.). I'm not sure they are even supposed to be in series with the motor supply, but may be depending on how the installation was done. My fix is simple ... bypass them.Not sure if these are used in ceiling fans marketed outside the U.S., but worth looking for them when dealing with problems in ceiling fans.Mike in California

author: tebbybabes
author_rank: Contributor
timestamp: January 03, 2020, 12:24:43 am
content: Yep, most of the stuff I found with correct specs on ebay were the the rectangular housed ones.Yep, I did find Mouser and it was the one place that had that round form factor but it was that pricey "snubber" cap category.I failed to run across digikey. Thanks heaps! It looks like they have exactly the one I need.As an aside, what exactly does "CBB20" mean? Is that a name for that particular shape of axial film cap?

author: andy3055
author_rank: Super Contributor
timestamp: January 03, 2020, 01:01:53 am
content: https://www.capacitorindustries.com/product-category/miscellaneous-capacitors/cbb20-polypropylene-capacitors/

author: tebbybabes
author_rank: Contributor
timestamp: January 03, 2020, 05:41:44 am
content: Quote from: andy3055 on January 03, 2020, 01:01:53 amMuch obliged, mate.

author: tebbybabes
author_rank: Contributor
timestamp: February 26, 2020, 06:08:48 am
content: Sorry for disappearing so long.I figured some of you might want an update. Anyway, my journey into this has been both a "success" as well as a "failure."After finally receiving the cap in the mail, I discover that it is massive and several times bigger than the one it was replacing. Thankfully there was enough space to bodge it together. The success part is where after soldering the cap in, everything worked! However, while the fan was now spinning faster than before, the SO was not impressed and to be honest, neither was I. Which brings me up to the failure bit. Because the performance from the fan was still under expectations, we decided I could stop faffing around with trying to fix it and purchase a replacement fan.So yes, we now have a new fan, and we are both more than happy with how it works. Shame I wasn't able to make the old one work satisfactorily. Thankfully though, I was able give it away rather quickly by posting it online. I explained what had happened with it and this bloke says he's got a mate that will be happy to tinker with it. So thankfully, it hasn't ended up in landfill.Anyway, just wanted to say thanks to everyone that helped and taught me in this little project of mine.Cheers!

author: andy3055
author_rank: Super Contributor
timestamp: February 26, 2020, 09:09:19 am
content: All is well that ends well!