Burnt resistor identification

Hello everyone,

I am new here and asking for help in identifying a burnt resistor from an ESPA water pump pressdrive circuit board, just can´t figure it out…
Thanks in advance for your comments.

carrretero:
Hello everyone,

I am new here and asking for help in identifying a burnt resistor from an ESPA water pump pressdrive circuit board, just can´t figure it out...
Thanks in advance for your comments.

It would be guessing, contact the pump manufacturer.

Its highly liklely some fault caused the resistor to burn out in the first place.

Whats the Arduino connection ?

Modified wave inverter caused it to burn. No other visible damage to the circuitry.

No arduino connection, I was just looking for a place where I might get an answer.

Sorry if this does not belong here.

Have you tried using an ohm meter on it?

You can also try mapping out the circuit to give some context as to what it's purpose is.

The thing is it only seems to have 2 bands that both look like red or brown, plus one at the end which might be golden.
Normally I would expect another band in between the reds/browns but there is no trace of it, I can´t believe the heat has wiped it completely

carrretero:
The thing is it only seems to have 2 bands that both look like red or brown, plus one at the end which might be golden.
Normally I would expect another band in between the reds/browns but there is no trace of it, I can´t believe the heat has wiped it completely

Maybe the missing band was white or the color of fried paint :wink: [I think I see a couple of such bands between the reddish bands].

Anyway, there isn't much hope of discerning original color [excessive heat can change the color, or make what, previously, were different colors, look, instead, the same], other than having access to [for instance] a forensics lab, where you can run samples through a gas chromatograph, or some such thing, to analyse the composition of the bits of paint, and do experimental resistor frying so you can compare known samples, to samples from your mystery resistor, etc.

Or, you could, possibly, collect a representative sample of resistors and fry them, and use those in comparison, and perhaps "logic out" the colors. But, I suspect there was a band in that exposed metal region -- and if so, even forensics may not help [unless comparing resistance measurements of fried resistors...]!?

But seriously...

Asking the manufacturer is the best idea...short of buying a new pump and pulling it apart to check the resistor in that. Anything else will be guesswork.

Steve

It doesn’t look like completely burnt out, measure the voltage whwre was the resistor.
Probobly this is 1W resistor so you can calculate resistance of it. R = V squared divided by P

  1. measure resistance
    2.put it back and apply power from your inventory for short time, look it’s getting hot - put drop water on it or saliva.
  2. connect to regular power supply.
    Why you need inverter ?

carrretero:
Modified wave inverter caused it to burn. No other visible damage to the circuitry.

No arduino connection, I was just looking for a place where I might get an answer.

So you powered the pump with a supply it was not designed for.

You could guess what the value of the resistor was and if you had the knowledge and experience to measure and work out what the resistor value should be then go ahead, but I guess it depends on your aversion to fires.

Sorry if this does not belong here.

Contact the pump manufacturer, they can advice you on what is the (safe) value of resistor to use.

ted:
Why you need inverter ?

It´s a pump a friend of mine was trying to use in his solar installation, unfortunately the pump did not like the wave his inverter is producing, so it stopped working after an hour (it was new from the box) and he asked me to check it, and maybe try to fix it.

Thanks a lot for all your comments!

For motor you need sine wave inverter not a pulses.
Google - sine wave inverter.

After reading the multi-language PDF, there is no information relating to the motor and controls, except to say, follow the parameters on the name-plate. So, what does the man-plate have on it and did your friend follow those values?

Paul