Varistor? Help ID Component

[hrhoward]

Hello,
Trying to identify a component on a board I'm working on.
Diameter is 4.75 mm and it is 2 mm thick at its widest.
On the board it is labeled R17 with the resistor symbol.
Any help is appreciated.

 

[danadak]

If you take a well focused pic of it and do a image search using google you
might be able to find it.


Regards, Dana.

 

[Delta Prime]

Trying to identify a component on a board I'm working on

I do have a crystal ball but it's buffering right now.
Photos and of the component itself, what device did the board come out of? Make, model, serial number, perhaps I can find a schematic. Geez

 

[hrhoward]

Dana, Delta Prime,
Thank you for replies.
I did use google's image search (photo below) with no success, unfortunately.

The board is an Amada Metrecs M0012A out of a NC9-EXII control on a Amada press brake. It is the CPU board.

 

[Delta Prime]

That is a 10pf capacitor. pico farad capacitor. Rf baby. And by the photos that's the least of your problems I doubt that capacitor failed.

On the board it is labeled R17 with the resistor symbol

Show me!
I have identified the component for you.
Now I'm willing to troubleshoot the board for you. What does it do what does it not do! Perhaps we can get to the bottom of this.
Marshall your thoughts it's late for me I have to go to bed good night to you give every and all descriptions you can . And I can fix it for you. Good night.

 

[davenn]

The board is an Amada Metrecs M0012A out of a NC9-EXII control on a Amada press brake.

what a massive corroded mess, that small capacitor is the least of your worries
there are other components are that severely corroded

 

[hrhoward]

Delta Prime, Thank you.
No, I don't think the cap failed either. There was a NiMH batt that decided to spread its influence around.
I was removing the components affected when one of the 10pfs kinda crumbled.
Guess I didn't listen to myself 'cause of the labeling on the board, R17 R18 along with the symbol.
Any idea what the black dot means?

After cleaning the area, going to reroute the damaged traces. Have done it many times over the last 20+ years.

The seven segment display along with the led's weren't lighting up. No signal from this cpu board. Power to display is ok.
That is why I focused on this board and discovered the bad influence the batt was having on its neighbors.

Still looking for a datasheet for it. No luck yet.


-HR

 

[Delta Prime]

Any idea what the black dot means?

It could be a black dot or a portion of the top of the capacitor is black indicating it is a NPO ceramic disc capacitor. Meaning negative temperature coefficient is 0 at room temperature.
It is used in circuits where frequency or timing accuracy versus temperature change is critical, such as RF filters.
That's why I said

Rf baby.

Have done it many times over the last 20+ years

Hey!!!!!????
I was just trying to help you.You seem to have all the answers so I'm out of here....
Big shot!