Timeline for Can this resistor be replaced by a wire or fuse?
Current License: CC BY-SA 4.0
17 events
| when toggle format | what | by | license | comment | |
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| Apr 17, 2022 at 6:00 | history | tweeted | twitter.com/StackElectronix/status/1515570762073190402 | ||
| S Apr 11, 2022 at 17:52 | history | suggested | Peter Mortensen | CC BY-SA 4.0 |
Copy edited (e.g. ref. <https://en.wiktionary.org/wiki/unfortunately#Adverb> and <https://www.youtbe.com/watch?v=1Dax90QyXgI&t=17m54s>). There isn't any need to declare a question or address anyone in particular.
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| Apr 11, 2022 at 17:39 | answer | added | supercat | timeline score: 1 | |
| Apr 11, 2022 at 15:27 | comment | added | Peter Mortensen | Related (meta): "Repair or modification" close change - (my emphasis) "Questions on the repair of consumer electronics, appliances, or other devices must involve specific troubleshooting steps and demonstrate a good understanding of the underlying design of the device being repaired.". Did the policy change? | |
| Apr 11, 2022 at 15:17 | review | Suggested edits | |||
| S Apr 11, 2022 at 17:52 | |||||
| Apr 11, 2022 at 10:44 | comment | added | seeker | That's how I understood Sam's comment @MSalters.... Anyway problem is now solved. First of all - the resistor in question was in fact surge limiting resistor. Next, the problem was in fact in broken relay (mechanical issue, resistor bypass contacts were not shorted even when coil was energized). And as much as I was tempted to simply remove resistor, I actually found two 30 ohms resistor with 10W dissipation power and soldered them in parallel. I've also checked board with thermal camea to make sure thee are no excessive heat. So while there might be other problem, I am very certain it's fixed | |
| Apr 11, 2022 at 9:24 | comment | added | MSalters | @seeker: I fear that SmaGibson's comment might not be explicit enough. The resistor might have been designed to handle at most 2 seconds of current, but due to another failure it remained active for much longer. It therefore had time to overheat. Simply replacing the resistor will then melt the new resistor too. You should measure the voltage over the resistor, and cut the power supply if the voltage over the new resistor does not drop within a few seconds. | |
| Apr 11, 2022 at 2:55 | review | Close votes | |||
| Apr 17, 2022 at 3:02 | |||||
| Apr 10, 2022 at 16:37 | comment | added | user4574 | What are the dimensions of the resistor? And will this one fit? digikey.com/en/products/detail/riedon/UB15-15RF1/5965578 | |
| Apr 10, 2022 at 13:34 | history | became hot network question | |||
| Apr 10, 2022 at 6:48 | comment | added | SamGibson♦ | seeker - OK, I'm glad my comment was useful. I deliberately wrote it as a comment, as it isn't trying to answer your question about whether the resistor can be bypassed. I just wanted to give a suggestion (guess!) of where a fault might be, to have caused the resistor to fail in the first place (e.g. due to overheating, if the relay contacts don't close to bypass the resistor a short time after power-on, when the capacitors have charged up). That way, as well as replacing the resistor, you can investigate whether there is an underlying fault, and perhaps fix that too. (Be careful with mains!) | |
| Apr 10, 2022 at 6:39 | comment | added | seeker | Now we're talking. @SamGibson I guess you're right... I will check PCB tracks in few hours and will get back but most likely you're right. Since: black, almost rectangular thingy is a relay and indeed relay 'clicks' after second or two after turning PS on. So I need to double check the PCB tracks but I'm very certain those are in series with mains, right after two HRC fuses | |
| Apr 10, 2022 at 6:31 | comment | added | SamGibson♦ | seeker - Just as a starting point if you can do any rev-eng: Judging by the location of that resistor, its rating & what might be a relay (black, almost rectangular, nearby), I wonder if that is a surge-limiting resistor which gets bypassed by relay contacts after a few seconds? Look at the PCB tracks. Is the resistor in series with one of the mains inputs? Do the relay contacts short out the resistor? If all of that is true then a possible failure mode is that the relay (or its timer that closes the contacts) has failed & the mains supply was passing thru the resistor continuously. Good luck! | |
| Apr 10, 2022 at 6:19 | vote | accept | seeker | ||
| Apr 10, 2022 at 5:53 | answer | added | Nedd | timeline score: 7 | |
| Apr 10, 2022 at 5:43 | answer | added | Kuba hasn't forgotten Monica | timeline score: 14 | |
| Apr 10, 2022 at 5:29 | history | asked | seeker | CC BY-SA 4.0 |