Trying to identify this "fuse"?

[ThePhoenix]

A bit of background, so as you know who/what you are dealing with.

I'm no electronics expert, but I was a hobbyist in my teens. My test and repair tool-set comprises a digital multimeter and a soldering iron.

I have an induction hob that has just stopped heating (the digital display works fine, just no power to the inductors). Before replacing, or throwing away I thought Id take a quick look for likely items that may have failed.

I can see that the left and right pairs of heating inductors separate power circuits which seem to be controlled by a common control board. As none of the rings on either side work I have assumed that this common controller is the issue.

The only mechanical component on this board is a relay, which I figured a likely point of failure and I have got a replacement for a couple of £ and installed it.

Before refitting the board I noticed the component in the attached photo. I'm assuming this to be a fuse? The only markings on it are those shown and I can't encourage Google to provide any help. My multimeter is showing it as open circuit.

Could anyone conform that this is a fuse and if so what, or how I might be able to determine the specifications of it?

Thank you for any assistance you can provide.

 

[Arouse1973]

Hello, happy new year. It could be a fuse, but I am not 100% on that. The markings are so no descriptive I am not sure. So there are no actual current rating indication like 4A which well could be 4 Amps, there are no voltage markings on the device and nothing to tell us if it's fast blow or anti surge. It's also only seven mm long, the smallest I have used for 240 Volts is 20 mm.

Is there any marking on the PCB from where you remove it. Like F1 or F something printed next to the holder. Can you take a picture on the unit so we can see where this component was fitted, it might give us some more clues.

Thanks
Adam

 

[duke37]

According to KrisblueNZ data, it is by MuRata.

Trevor

 

[Arouse1973]

Yes your right Trevor, I forgot about them. Just searched their website but can't find any fuses apart from PTCs
Adam

 

[ThePhoenix]

Thank you for the very prompt replies. Please see the attached photos, as requested.

The area circled in red is where the component was mounted. The close up shows the pads to which it was soldered. It can be seen that the PCB is labled as X1 at this place. Might it be that it is just some sort of test point, maybe?

 

[davenn]

HI
welcome to EP


it's NOT a fuse

its a 4MHz crystal for that processor chip to its right


Dave

 

[ThePhoenix]

Brilliant, thank you. I'd better put it back then!

Thanks all.

Regards
Paul

 

[davenn]

Brilliant, thank you. I'd better put it back then!

Thanks all.

Regards
Paul

yup and don't over heat it with the soldering iron

 

[Arouse1973]

Ah Dave you stole my thunder....It more likely a resonator. I Knew something was odd about it.
Adam

 

[Minder]

Odd they use the X designator, usually a crystal has a Y designation.
Max.

 

[davenn]

Odd they use the X designator, usually a crystal has a Y designation.
Max.

I see a pretty even mix of either X or Y,
actually thinking about it ... probably more X than Y

 

[Minder]

..I have generally come across the opposite!
https://en.wikipedia.org/wiki/Reference_designator
Max.

 

[ThePhoenix]

Just an update as to how things have gone.

I resoldered the crystal/resonator back to its home, being careful with the heat (davenn) . Then put the board back in the hob. It all fired up fine, so problem solved? Not quite.

40% of the time it will work fine, but for the other 60% it look to be working, but, as before will not (induce) heat. New information is that even when it is working the touch controls seem to have a subtle issue, that being that if the power is ramped up to the highest figure of 9 and ones finger is removed, it then becomes impossible to subsequently change the value (up or down) from then on. Level 9 has a special function in that a 'new' touch command requesting a power increase to a ring set to 9 should power it off.

The fact that this is working some of the time makes me want to think that this possibly an under voltage supply issue, or a passive component failing, as I assume semiconductors tend to work, or not. Is this a foolish assumption?

Given my lack of experience and testing equipment, should I just give up now, or would anyone think it possible that I may be able to find a schematic for this hob (Neff) and do a bit of voltage checking (or other tests), that may get me somewhere?

Thank you for any advice.
Paul

 

[Arouse1973]

Hey Paul.
The best thing you can do is to look for dry solder joints. Inspect all solder joint for dull or cracked joints. This might help. If it looks suspect then re-solder it.
Adam