Electrical heater controler

[tomalamix]

Re: Electrical heater controler

With 5.8vac into the bridge you should get about 8vdc out, so it could be that the bridge is bad.
Just to be sure I see two diodes around C18 This is the one I meant Z???
Is the diode connected across C18?

back to the project now...

The diode is connected to C18 and is a EIC65 218D5. Can't find anything on the web about it.

What about the bridge output, how to be sure about how much voltage should be in the Output? By reading the datasheet i cant be sure.

thanks

[tomalamix]

Re: Electrical heater controler

Hy,

Did you had the opportunity to check my message? thanks!

[tomalamix]

Re: Electrical heater controler

With 5.8vac into the bridge you should get about 8vdc out, so it could be that the bridge is bad.
Just to be sure I see two diodes around C18 This is the one I meant Z???
Is the diode connected across C18?

Hy!

How do you know that the output value is 8 VDC? I cant get that from the datasheet. Sorry to ask.

thank you!

[R_J]

Re: Electrical heater controler

With 5.8vac into the bridge you should get about 8vdc out, so it could be that the bridge is bad.
Just to be sure I see two diodes around C18 This is the one I meant Z???
Is the diode connected across C18?

[tomalamix]

Re: Electrical heater controler

I missed that 2.4v, Yes that is too low, There seems to be a zener diode next to C18, what are the numbers on it? Also what is the value of C18? try replacing C18

I've replaced C18, problem remains. Ther diode next to C18 is a EIC41 218D5 , can't find anything on the web about it, testing values are Uf=712mV C=599pF.

I'm starting to give up about this, I can't see anything obvious failing...

[tomalamix]

Re: Electrical heater controler

You will need to measure the voltage into the bridge rectifier It will not be 220vac as it is dropped through two resistors.
Measure the AC voltage across the two pins marked ~~ Then measure the DC voltage across the pins marked - +

Ok, measured in the ~~ side, there is 5.8V AC, both resistors are inside the expected value.

On the +- side there is 3.8V DC

I've solved the grounding wire that wasn't properly connected but the problem as returned to stage 1, the light fades away, so does the LCD display, but now its worst, the unit doesn't come up after a few seconds stays apparently Off without responding to any inputs.

[R_J]

Re: Electrical heater controler

I missed that 2.4v, Yes that is too low, There seems to be a zener diode next to C18, what are the numbers on it? Also what is the value of C18? try replacing C18

[CapLeaker]

Re: Electrical heater controler

If you had 2.4VDC on the output of BR3, I think that is not right. Check those SMD resistors between the 310v cap.

[R_J]

Re: Electrical heater controler

How much voltage should be in the output since the input is 220V ? By reading the datasheet I can't understand the correct value.

You will need to measure the voltage into the bridge rectifier It will not be 220vac as it is dropped through two resistors.
Measure the AC voltage across the two pins marked ~~ Then measure the DC voltage across the pins marked - +

[tomalamix]

Re: Electrical heater controler

B10S must be the numbers on the bridge rectifier BR3, this bridge contains four (4) diodes.

How much voltage should be in the output since the input is 220V ? By reading the datasheet I can't understand the correct value.

[tomalamix]

Re: Electrical heater controler

Well, I've tested it, i've connected the 220V on the line of the PCB and measured the output on the B10S. There is 2.4V, i think its working properly.

Meanwhile I've detected a pin without proper grounding, the wire that connects there is not conducting properly, I'm going to change this wire and test again everything, i'll keep you guys posted

[R_J]

Re: Electrical heater controler

B10S must be the numbers on the bridge rectifier BR3, this bridge contains four (4) diodes.

[eccerr0r]

Re: Electrical heater controler

I don't know where the "BC B10S" you're working with is on your board.

I can see a BR3 designator on the PCB and that's a bridge rectifier that should contain 4 diodes. Having 4 pins I'm not sure how you got it into a 3-pin avr transistor tester?

Hmm...capacitor dropper psu...

[tomalamix]

Re: Electrical heater controler

Ok, i've uploaded the photos, I don't have any other camera then the phone so this is waht I can send. Searching around I can't see anything out of ordinary, nothing roasted, not even that typical smell is present.

Some notes about the photos, I've rebuilt a track that i've destroyed near the polyester capacitor, but it was working before so the problem isn't there. Another thing is that the new polyester capacitor is 310instead of 275V if that matters.

About the rectifier, I see there a BC B10S just after the polyester capacitor., is this a rectifier? This means something to you? Is the one near the right yellow capacitor.

Ok, meanwhile I've been reading around and this BC B10S is a two in one diode, it rectifies the voltage from AC to DC, right? Instead of having two separated diodes doing that there is this BC B10S.

Done some testing between the rectifier poles, the ESR02 gave be me a thing like: 2* >| (DIODE SYMBOL) \ 2 >| 3 >| 2 \ Uf= 2,23V 700mV

On the other "channel" gave me 2* >| (DIODE SYMBOL) \ 2 >| 3 >| 2 \ Uf= 700mV 2,23V

[CapLeaker]

Re: Electrical heater controler

Can you upload new straight shot high resolution pictures? Maybe we can see something where the smoke came out.

Check for DC voltage at the bridge rectifier next to the 0.47uF cap. Recheck the other cap for proper orientation. Check for open or higher in value resistors than spec. Bad diodes… etc.

[sam_sam_sam]

Re: Electrical heater controler

The 4.7uf@50 volt is still a little to high it would be better if was 1.something to maybe 2.something but this might be pushing it depending on what the circuit is requiring ( mind you this is a new capacitor for this value )

I do not have any 0.47uf you do have the voltage listed 4.8 might be a little high as well I have to look and see if I have any of this value

Have you found a switching power supply regulator on this board yet if you do list the part number for it so I can look up the data sheet for it

[tomalamix]

Re: Electrical heater controler

Ok, i've tested the ESR02. The new capacitor 4.7uF 50V is reading 4800nF, 4ohm for ESR and Vloss 3.5%. It's not perfect but better than the previous.

The new 0.15uF reports 145nF, no ESR value again and no Vloss. At least the capacitance is in the right range.

The 0.47uF testing gives me 480nF with 4.8ohm ESR, no Vloss value too.

Everything assembled and the unit worked properly!! But only for...20 seconds...

The back light was on, the power LED was on and I was changing the temperature setting with everything visible in the LCD, but all that stopped working in a few seconds and never came back again. Now I can't turn on the unit, no LED, noe LCD, no relay kicking in, nothing...

I've opened everything again but I can't see anything out of the place, i'm lost now..

[Per Hansson]

Re: Electrical heater controler

Yes you should change them both, and when you get the new ones test them on the meter:
Because it needs to be properly calibrated to be able to show values this low with confidence, so it will be a good test for the meter too

[tomalamix]

Re: Electrical heater controler

I'd change the 275V 0.47uF and the 4.7uF 50V and see what happens.

Ok, i'll go for those two, but what about the 0.15uF that reports 1005pF ? It's not worth to swap too? Am I doing something wrong? Sorry for the silly question..

[CapLeaker]

Re: Electrical heater controler

I'd change the 275V 0.47uF and the 4.7uF 50V and see what happens.