Can a carbon film resistor still be used if the skin falls off?

sky999

Can a carbon film resistor still be used if the skin falls off? [Copy link]

I put the circuit board in an ultrasonic machine to clean it, and the skin of the carbon film resistor was washed off. It didn't come off completely, but it came off as soon as I wiped it. Can I still use it? The resistance value is still normal, and it is normal when it is powered on. I just don't know if it is insured.

maychang

In the days of scarcity, you can measure the resistance value after drying. If the resistance value does not change, I suggest you paint the surface of the resistor and continue to use it. But now, I suggest you change a resistor supplier and discard this board.

1350774640

I put the circuit board in an ultrasonic machine to clean it, and the skin of the carbon film resistor was washed off. It didn't come off completely, but it came off as soon as I wiped it. Can I still use it? The resistance value is still normal, and it is normal when it is powered on. I just don't know if it is insured.

beyond_笑谈

The outer skin of the carbon film resistor has fallen off, but it can still be used. I have seen similar situations on boards before, where plug-in carbon film resistors were used.

luominxdy

In the days of scarcity, you can measure the resistance value after drying. If the resistance value does not change, I suggest you paint the surface of the resistor and continue to use it. But now, I suggest you change a resistor supplier and discard this board.

吾妻思萌

It doesn't matter if the outer film is broken, the color ring or the protective paint is broken, it doesn't matter if the inside is fine.

But why do you use ultrasound to clean this thing?

sky999

maychang posted on 2024-8-28 15:08 In the era of material scarcity, you can measure the resistance value after drying. If the resistance value does not change, I suggest that you continue to use it after painting the surface of the resistor. But now, ...

It's not the resistor's fault. The acid in my ultrasonic cleaning water seems to be too strong, and the color of the plastic has changed.

wangerxian

Just test it, if it's OK, just like the boss said, paint it, just to be safe.

吾妻思萌

I looked carefully at the carbon film package and it seems that there is no problem with ultrasound.

The structure inside should be very tight.

sky999

Azuma Simeng posted on 2024-8-28 17:07 I carefully looked at the carbon film package and it seems that there is nothing wrong with the ultrasound. The structure inside should be very tight.

OK, thanks

chunyang

The surface coating of the resistor will not be damaged by the ultrasonic cleaner unless there is a problem. Note that the coating of the resistor itself is completely different from the paint sprayed later. If the surface coating of the resistor is damaged, the resistor should be replaced because the resistor film will absorb moisture when exposed to the air, which will affect the resistance value.