Biomass Boiler not driving cleaner motor relay. ENERTRES BIOMASA BI-650

[edugimeno]

Ok final update on this with conclussions. Summarizing: Client states that one of the functionalities of the board (pellet ash cleaning motor) is not starting, neither during normal operation, nor during tests screen,

There is one relay in a row of several, that clearly drives the 230V ac voltage to the cleaning motor. Before any other test, I try to apply 24v dc to all relays directly and they all click on-off but this-supposedly-faulty -one goes like slow and weak. I measure all driver transistors and all give the same readings but the ones driving this relay. It seems that 2 transistors drive each relay in aparallel like and OR gate.,

I replace these 2 transistors and turn the board back to the client.

He tried it yesterday on the boiler and called me to state....: IT ALL WORKS PERFECTLY NOW!!

So somehow I may have damaged these transistors but they were already damaged because just by replacing them the board came back to life...

Despite being my fault or not my conclussion is that I still don't master the abilities to repair an electronics board as some of my testing techniques are dangerous...That's why even when I believe I can go ahead with some repair, I always come to this forum to get some assistance. In this case I tested the relays before...

Thanks everyone!!

[sam_sam_sam]

Ok final update on this with conclussions.

He tried it yesterday on the boiler and called me to state....: IT ALL WORKS PERFECTLY NOW!!

So somehow I may have damaged these transistors but they were already damaged because just by replacing them the board came back to life...

Despite being my fault or not my conclussion is that I still don't master the abilities to repair an electronics board as some of my testing techniques are dangerous...That's why even when I believe I can go ahead with some repair, I always come to this forum to get some assistance. In this case I tested the relays before...

Thanks everyone!!

The one thing that is very important to understand is how the circuit works one rule that I have is when I see mechanical relays to test them I remove them from the circuit board because 95%of the time there is some type of protection circuit that keeps the circuit from being damaged by emf or electrical spikes

When checking optics sensors is a little tricky sometimes to in that you have to have the positive and negative correct when checking the LED side of the device with a meter in diode mode

One thing that is very helpful is to look up ic chips for what the pin outs are and what they are and how they are supposed to function

Google is your friend and also You Tube is also your friend as well this how I have learned a lot about electronics and how to repair stuff like this

One note do not be so hard on yourself because you are learning something that you do not have very much experience with as you do more research and repairs you will learn more about how different circuits and how different components work

I can not count how many times things have gone wrong when trying to fix something that I did not do the research that was required to have some kind-a understanding of how the circuit works and this is how you can get in trouble but remember that this is also a learning process and that this is part of it

When I first started repairing electronics devices like lcd monitors and switching power supply I came across this forum and hung out here for a long while before I found a couple of monitors that did not work and I wanted to repair them I got help from some people on this forum that took the time to point out how to research different devices and how to understand how and what functions the device does and how to check ic chips

As far as repairing switching power supplies I learned a lot from hanging out around here and YouTube videos and watching videos very closely and playing them over several times until I understand what and how they were doing it

Congratulations on the success of your repair on this device I have been following your progress on this repair because I also have learned something from it as well

One more item that did not end up in the landfill

[edugimeno]

Yes Sam, thanks for your comment. Definitely I can't count as an experimented repairman, I have been "into" electronics for the last 35 years but always in the amateur side. I've always been an IT specialist and only recently with a morecomfortable job with more spare time, I've started offering my services sporadically to some known people and some of them have spreaded the voice so now there's like 10-15 people who call me from time to time to bring a TV, amplifier, car stereo, power supply or other weird piece of electronics that I have to repair and only very recently I have started charging them for the repair.
I see that I can't really charge them for the REAL time invested in the repair ,by far. Like you said, as soon as I find out the brand and model number, I start searching for information, schematics, common issues, badcaps entries, etc about that model and read as much documentation as I can. I may have repaired like 50-100 devices in the last 4-5 years and most of the times I've charged like 50-100€ for many of them. That's like 1 or 2h work depending on salaries, for repairs that usually have taken up to 8h in total...PRE-study, open, remove probably damaged IC's, Q, D's, order them, solder new ones, close, test, etc...
Most of the time I do this because every repair turns into a challenge for me and I NEED to prove myself that I can repair it, and I feel SO proud when I fix it! And then if I can even get some money for the repair, wow, double prize

I guess Im not the only like in this situation around here

[sam_sam_sam]

I NEED to prove myself that I can repair it, and I feel SO proud when I fix it! And then if I can even get some money for the repair, wow, double prize I guess Im not the only like in this situation around here

One thing that I have learned about what to charge for a repair is how much time does it take to replace the parts that are needed plus a couple of hours of continuous research but the time to find all the information needed to do the repair this might not be the right way to do this but it the gain in knowledge is priceless because the next time you will make your money back when you first research the issue or issues with a given device for repair

I also repair devices for customers but I do not most of the time I do not give a quote because I really do not know what it going to take to repair a device but I will tell customers that there is a minimum of 4 hours that I will charge you if I have spent many more than 4 hours to repair there device

[edugimeno]

Yes, I find that in electronics repair its more difficult than in other jobs to provide an accurate quote and to charge for the real time you have spent. I guess mechanic car repair is kind of alike. You have an impression of what could be broken, given your own experience in similar products you have repaired (TV shows no image, but has sound, you EXPECT to replace the backlight strips), or just after a quick examination (SMPS chopper transistor shows a burnt spot, you EXPECT to replace the Q and call it good) but there there are many times that you end up spending a long time you could not have expected, sometimes because you overlooked something on your first examination (DC converter IC in the back side was burnt too) and if you sum up all the invested hours there's no way a client would pay that amount, probably closer of higher than purchasing a new product. Yes some of that can you can call it "invested into learning" but sometimes that goes way beyond that....

[sam_sam_sam]

Yes I would agree with you for the most part except that when you have reached the point of “no return” and it not going to be practical to charger the customer you can walk away or if you told the customer that there is a minimum charge weather or not I can fix or not I still should get the minimum charge that the customer agreed to now weather or not you can collect on that or is another thing now is it worth pushing the issue that is a hard call

I have a minimum charge that I charge customer when I am pretty sure I know what the issue is and I can fix it but there have been times that I have spent several hours when the customer problem is more than just the obvious problem because it more than one problem a device can have just like the example that you gave the one thing that you can take away from this experience to look the hole job more throughly but let just say for the sake of this example that after many hours you do get the device working because the customer gave you the device so now the question what do you do now do you give the device and charge them for what the gob should have cost if you had all of the knowledge from the beginning or you do not say anything at all and learn from the experience and call a day not a good place to be in because I have been there before