Hi all,

This resistor is reading a 56K Ohm with my DM however the colour code chart suggest it’s a 0 Ohm resistor. The colours are Black Black Brown and Gold.

Thanks

 

The resistor was removed from SMPS.

 

The color code does read 0 ohms.
Normally used as a jumper or even as a fuse since it's reading 56K ohms
Are there any more on the board with the same color code?

 

Hi Sghioto,

Thanks for your reply,

No it’s the only resistor on this board.

 

The resistor was getting very hot when it was attached to the board.Hence why I removed it but I don’t know which to trust as for the correct value! My DM or the Colour code.

 

Can you trace to see what is connected to the resistor?
What is the make and model of the instrument?
Post clear photos of both sides of the board.

 

Thanks MrChips,

Both side are connected to a diod.

 

Hi Tech,
A photo of the other side of the PCB would be more helpful,
E

 

What's the reference designator hiding under the yellow wire? A zero ohm resistor usually just has one black band in my experience.

 

This resistor is reading a 56K Ohm with my DM however the colour code chart suggest it’s a 0 Ohm resistor.

Unlikely to be getting that hot if it's a 56KΩ resistor. Check the batteries in your meter. Weak or dying batteries can give grossly inaccurate readings. The color code - as others have said - is zero ohms. If it's factory original then there's something else drawing massive current through it.
View attachment 360230
As for it being the only resistor on the board, there's a resistor in the image up in the upper left corner. Then looking at the back side - there are many more resistors. In the image below I see what looks like diodes, I definitely see resistors and a few transistors (or MOSFET's as the case may be)
View attachment 360231

What's the reference designator hiding under the yellow wire?

My GUESS is "R3". Which is another indication there are more resistors than one.
[edit] Could be R23, 33, 63, 83, 93 or even 03. [end edit]
Can you give us a part number of the PS? Someone may be able to track down a schematic, though that's slim.
Bottom line - something else is wrong causing the resistor to get hot. Does the PS work? Does it exhibit unusual characteristics? If so - what? How?

 

Sorry, your photos are not useful to me in order to reverse engineer the board.
Why is there a blue tint on the photos?
We want to see the entire board and must be able to see where the PCB tracks run on the board. In other words, we want good contrast between the tracks and the bare green board, best seen in natural lighting and colour. The angle of the lighting can enhance the contrast.

You have not told us the make and model of the gadget,

 

Am I the only one using a decent computer Display?

I clearly see Green Blue Brown Gold (right to left) in the photo of post #1

560 Ohms 5%

I assume that "brown" is actually orange that is a little burnt. 56K, 5%

??? !!!

 

My GUESS is "R3". Which is another indication there are more resistors than one.

Why guess? The component in question doesn't make sense as a resistor:

● zero ohm resistors usually have a single black band.

● 56k resistors would not be marked like the picture.

The reference designator will show if it is a resistor or something else.

 

it may be 56k that simply got discolored due to heat or bug zapper light used as a light source..
DC bus after rectifier is often some 300-320VDC. if connected across it , 56k would dissipate 1.6W which can be quite hot even for the size shown. to deduce role of this resistor on the board, clean pictures of both front and back are needed, along with clear picture of any IC, specially the DIP16 one.

 

It looks like a fusable resistor. If this is the case one side of it will probably connected to the mains live input. Can you measure the resistance between the live input and each of the solder pads on the board where the resistor was connected..
Les.

 

Why guess? The component in question doesn't make sense as a resistor:

● zero ohm resistors usually have a single black band.

● 56k resistors would not be marked like the picture.

The reference designator will show if it is a resistor or something else.

I assume that "brown" is actually orange that is a little burnt.

Burnt would definitely be a possibility.

You have not told use the make and model of the gadget,

For sure!

it may be 56k that simply got discolored due to heat or bug zapper light used as a light source..

Where did you get "Bug Zapper" from? Did I miss something? Are you saying the light source might be a UV lamp?

 

Here are some tips when asking for advice on an electronics repair.

You cannot just pull a component off a board and ask us to identify it.
1) First of all, state the make and model of the instrument or device.
2) Show us clear pictures of the entire board, not just the portion from where the component came.

In order to identify the component, it helps to identify the function the component plays in the entire circuit, or at least that part of the circuit.

While we can guess the function, a circuit diagram would remove any doubt. Failing that, one needs to reverse engineer the board in order to create the circuit diagram.

 

Wow I went to have my dinner and came back to see all the reply, thanks all.

the marking is R33
I apologise for the low quality image as I don’t have any source of light maybe I will try again in daytime.
what I meant that resistor is the only one of its size otherwise there is plenty of small ones and SMD ones.
the PS is not working it is for halogen lighting source for my microscope.
The reading on my DM is correct but the colour code chart confused me a little.

 

Black = 0
Brown = 1
Red = 2
Orange = 3
Yellow = 4
Green = 5
Blue = 6
Violet = 7
Grey = 8
White = 9

Gold ± 5%
Silver ± 10%
No Band ± 20%

56KΩ would be Green / Blue / Orange = 5 / 6 / 000 A gold band indicates a tolerance of ± 5%. Yours is a 3 band resistor. The fourth band (the gold band) indicates a tolerance of 5%.

That's in a 3 band color code. There is also 4 band, usually for precision resistors with 1% tolerances.

 

Thanks for the tip MrShip,