IN2500i Generator Inverter.  - Page 1
Forum section: electronics / repair

author: drforshaw
author_rank: Newbie
timestamp: March 09, 2020, 03:16:36 pm
content: Hi everyone, new to the forum and looking for some help.I am trying to repair an inverter board from a petrol generator and I'm struggling to confirm what the attached part is and where to get it. From reading the markings I think it's a 15watt 0.16 Ohm ceramic resistor but I just can't find it anywhere or even something I can substitute it for.Thanks for any help!

author: Zero999
author_rank: Super Contributor
timestamp: March 09, 2020, 05:11:45 pm
content: R is commonly used as the decimal point symbol, so R016 is .016Ohm, i.e. a 16mR resistor.16 is a standard E24 number, but finding such a low value can be challenging. You might be able to get away with 15mR.https://en.wikipedia.org/wiki/E_series_of_preferred_numbers#E24I suspect there are other parts as well as the resistor, which are bad.

author: drforshaw
author_rank: Newbie
timestamp: March 09, 2020, 05:21:48 pm
content: Thanks zero999, I will start looking in that direction for something had a feeling I had a decimal point in the wrong placeYeah there are a few things dead on this board, diodes, caps, possibly the 3phase driver, 15v and 9v regulator .Don't get me wrong I don't think it was all broke originally but I have been slowly killing it with every test and bodge. It has went bang at least 3 times now after testing.But I am sure I can bring it back to life. Somehow....Digging out the board from all this black potting compound has been a challenge in its self.

author: JKKDev
author_rank: Regular Contributor
timestamp: March 09, 2020, 06:28:23 pm
content: Where did the majority of the C13 cap goEither it uses air as dielectric or there is something very wrong there( left of the left-most red component)EDIT: Just noticed another one just north of the chip with the I R logo. I don't want to sound mean as I know just how tough the potting compound is but you did a number on this board. I hope you are able to salvage it

author: schmitt trigger
author_rank: Super Contributor
timestamp: March 09, 2020, 06:43:16 pm
content: Why do you want to substitute the resistor?Is it open circuit?When I have seen this happen, that an extreme overload opened up the resistor, there will be tell tale signs of a severe overheating.The exception to the rule are resistors with an internal thermal cutout. Non-reseteable.

author: drforshaw
author_rank: Newbie
timestamp: March 09, 2020, 08:14:08 pm
content: Haha yes this board has been to hell and back. I was trying to find a short at first and to try and avoid removing all the black potting I thought I would just rip them off to see if the short would go away. As you can see I tried this a few times with no joy. Lol so started the laborious task of removing all the potting.You will be glad to hear that all the caps have been replaced with nice new ones and it's on the mend to recovery.

author: drforshaw
author_rank: Newbie
timestamp: March 09, 2020, 08:22:56 pm
content: No the resistor is not open circuit but I wasn't sure what the reading should of been.At the time I was trying to find out why the rectifier to the left of the resistor was showing continuity across all 3 pins I thought something might have happened to that resistor but turns out I was following the wrong rabbit.This board has a good number of problems some of which I have caused. Doh! But hey you learn through mistakes right?I am needing to find a transformer for it though or come up with a work around. I think the board was subjected to weather and the transformer had rusted and snapped off the board. In true bodge style because I couldn't figure out a part I took the old one apart and rewound it onto another core but I don't think it has worked very well.Lesson 25 learned.

author: Zero999
author_rank: Super Contributor
timestamp: March 09, 2020, 08:57:17 pm
content: A resistor with that lower value should read a dead short circuit, on most multimeters which won't be able to measure such a low value resistance.In general resistors under a several hundred kOhm fail open, as the element burns out and much higher values drop to a much lower value, as the surface coating chars or the element undergoes a high voltage breakdown.