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Son of Samurai's Blog

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How to Identify Unfamiliar Parts in Schematics

Son of Samurai


Take a look at the cooktop schematic below.

Screen Shot 2020-05-06 at 2.03.01 PM.png

I don't know about you, but "tranformator" isn't a familiar term to me. it certainly sounds like a transformer, but why would a transformer be necessary in a 240 VAC cooktop element circuit?

The best thing to do here is to look up the part numbers for the "transformator" as well as other key components, such as those cooktop switches that the transformator is supplying power to. Then we can use a parts site to look at physical pictures of the parts.

If you grab the part number for the transformator and plug it into repair clinic, you will see that it does have a transformer on it. But looking closely at that picture, you'll see a couple of other things. For example, you'll see two capacitors and four diodes. The diodes and the capacitors form a rectifier circuit.

Screen Shot 2020-05-06 at 2.26.06 PM.png

So what do you have going on with this transformer or "transformator" is a transformer that is producing several secondary voltages, some of which are being rectified and filtered into a DC voltage which is then used by the surface switches.

Why would the surface switches need DC voltage? Let's look them up in the same way! You will see this that this isn't a typical infinite switch. This is an electronically controlled infinite switch which includes a built-in LED display -- hence the need for the DC voltages. 


And just like that, with a couple of quick parts look-ups, we've identified an unfamiliar component and made sense of a strange-looking circuit. All in a day's work for an Appliantologist!

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I recall reading in a scientific journal somewhere that with a transformator,  one can make a flux capacitor open a time warp without the need for traveling at 88 mph.  lol


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It seems to me that this is just a mistake on the schematic or if it is spliced in this way It wouldnt Matter really as long  the dcV is  the same at the transformers P5  Pins 2,3  ?    I noticed that the right rear switch's P5  Pin 2 wire going  to the transformers P3  Pin3 connection.   The other 3 switches P5  Pin 2 wires all go to The tranformers P3  Pin 2 connection.   Is this why that flux capacitor can use a lower MPH ??    :kopkrab:

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Son of Samurai


Very good spot, @darren412! I think you're right -- that has to be an error in the schematic. I can't think of a reason why they would actually wire it like that. Here's what we're talking about for anyone who missed it:

Screen Shot 2020-05-08 at 10.08.24 AM.png

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