Susan Brown

[Susan Brown]

yep!

[Susan Brown]

Hi Scotty,

Electric dryers have some of the most interesting schematics, because the elements need 240vac (L1-L2), but the motor just runs off of 120vac (either L1-N, or L2-N).

Look at the motor on the dryer schematic (the bottom one – the top one is for the washer). The neutral line comes in from the top, and the hot line comes in from the left on the brown wire. Do you see that, and whether that is L1 or L2?

[Susan Brown]

This is a perfect question for the Dojo at Appliantology. There have been previous conversations about home warranty companies. Search for those threads, or start your own. We do not have direct experience with home warranty companies, but a number of our members do, and apparently some are okay and others are terrible to work for.

In general, a small percentage of warranty work (either kind) can be useful in getting you experience and connected with customers who will hopefully call you for any COD work they have in the future. You just need to proceed carefully in terms of which companies you connect with, and don’t ignore building your COD customer base through other means as well.

[Susan Brown]

The hardest and most valuable part of appliance repair is doing a correct diagnosis so that you know which part to replace, so that’s where we focus our teaching.

Actually replacing the part is normally straightforward, and there are instructions provided by the manufacturers and/or tons of free videos on YouTube showing the parts changing.

See this article at the site for more info:
https://mastersamuraitech.com/hands-on-appliance-training-resources/

[Susan Brown]

1.Very important not to mix up voltage and current!

From Unit 7:

The three most common electrical measurements you’ll be doing as a professional appliantologist are:

– Voltage, either DC or AC
– Resistance and its daughter test, Continuity
– AC current, which is always done with a clamp-on amp meter (or ammeter). (Note: You will never need to measure DC current in appliance repair.)

2.From unit 9:

– AC does not have a polarity in this sense because its current direction is reversing 120 times a second. Instead, in AC, we talk about the hot wire and the neutral wire. That’s why when connecting wires to an AC component like a solenoid valve or switch, it doesn’t matter which wire goes on which terminal.

[Susan Brown]

Hi Mike,

We don’t have enough first-hand knowledge to give you a firm recommendation. We do have students who will combine our training with an on-site school like Fred’s or Dyer Academy. They are both reputable schools. But because it’s quite a lot of money, most of our students find other ways to get hands-on practice, either by working on appliances for friends/family, acquiring used appliances to practice on (and maybe sell), etc., or by working for an appliance repair company for a few years or so before branching out on their own. Some people we train just jump right into offering professional repair service and basically learn on the job!

[Susan Brown]

We’re always glad to help!

[Susan Brown]

Take another look at the video in Unit 6, especially the slide starting a little before the 3 minute mark. The voltage on the primary side is very high – 2400 to 12000 volts, so putting the 240 one wave there wouldn’t make sense.

The 240vac supply doesn’t ever actually exist. We only induce it by having a circuit with L1 and L2 as the power supply. The difference of L1 and L2, since they are 180 degrees out of phase, creates the 240vac. That’s what the black line you’re talking about is showing.

You don’t really need to understand it much more deeply than that as an appliance tech. However, here’s a more detailed paper talking about power supply that you can download if you’re interested.

https://appliantology.org/files/file/3147-120-and-240-vac-single-split-phase-multi-wire-branch-circuits/

[Susan Brown]

I have multiple electronic books, but I have yet to find any sinusoidal drawings of our 120/240 split phase systems. At the moment, I do not have one to reference that system.

Most electronics books don’t spend much time talking about AC power supply, since electronics are generally only concerned with DC.

If you do a search for split phase power you can find all kinds of sine wave graphs. Here’s another cool one:

[Susan Brown]

Hi Ian,

The black sine wave is the resulting voltage from L1 and L2. The x-axis is labelled: “240 volts AC = (Phase 1) – (Phase 2)

Note that it is not drawn with a mirror image of itself like the waves for L1/L2 are.

Does that help it make sense?

[Susan Brown]

Even though you got it correct on the quiz, I commend you for taking the time to make sure you understand it!

Let’s make sure we’re talking about the same thing.

If everything was working as it should, you should be getting 120vac supplied to both sides of the element – 120vac from L1 and 120vac from L2.

We carefully disconnect L2 from the element while the dryer is still plugged in, and measure 120vac from that disconnected L2 wire wrt N. That means there is not an open along that side of the circuit.

Then we measure the L1 side of the circuit and get 0vac wrt N. This means there is an open somewhere up the L1 circuit, preventing the L1 voltage from being felt at the element.

I’m not sure where your confusion is coming in. Remember, we’re measuring voltage (L1 or L2) with respect to a neutral point, not measuring two points along the wire.

If this doesn’t make it clear, please let me know where you are getting hung up and we’re happy to help you further.

[Susan Brown]

Yes, and you can see that P2 is 1000 times higher than P1.

This supports what I said in my first reply to you that since P and R are directly proportional to each other, you could answer this question just by seeing that R2 is 1000 times higher than R1.

It’s great to do the calculations to understand it all better, but it’s also good to know the relationship of P and R!

[Susan Brown]

It’s not where you were posting, it’s what. You were asking questions about reading schematics. Unless I’m mistaken, these were not for a job you were going on, but just to practice reading schematics.

My point is that you will get a lot more practice reading schematics in the Oven & Range course as well as Advanced Troubleshooting. These courses will help you get better, and you can ask us questions here about those schematics without worrying about posting a picture, because we’ll be talking about schematics that are included in the courses.

[Susan Brown]

Hi Mike,
Questions about refrigeration or Refrigerator technology, like what you asked above about the ADC board, are fine to ask.

It’s the questions about reading schematics that we’d prefer you wait on until you’ve taken the other courses, which will give you more instruction and practice on reading schematics. You’ll benefit a lot from taking those courses! And it would be better if you asked us questions on the schematic exercises and case studies in those courses – it would make for more fruitful dialog.

[Susan Brown]

The question shows two loads in series: R1 and R2
R1 = 5 ohms
R2 = 5k ohms

It’s asking how much more work is done by R2.

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