Wow, what a great Schematic Lab Webinar we had. It was a Schlabinar!
It was our biggest turnout yet for a live webinar. This is a topic that serious students of appliantology can’t seem to get enough of, and I’m not surprised. As y’all know, I preach the virtues of pre-diagnosis, schematic reading, and troubleshooting. These are the premier technical skills we can possess as technicians. Interpreting the mystic scribblings that the manufacturers provide on their tech sheets requires quite a bit of background knowledge, such as understanding basic electricity, series and parallel circuits, and Ohm’s Law, not to mention collaboration with your Brethren in the Craft.
As with all skills, however, it gets easier with practice and knowledge, which was exactly the point of the Schlabinar. We pored over the actual tech sheets for 5 different appliances, using them as a springboard for diving deeper into the interpretation of these documents as well as their use in your troubleshooting.
If you missed it, or would like to review it again to fully absorb all of the info, you can watch the recording and download the tech sheets we reviewed here (NOTE: you must be enrolled as a student in the Samurai Tech Academy and logged in).
Loose electrical connections cause multiple problems in appliances, heat being the most common one. We've all seen burnt wire nuts in a dishwasher power junction box or on a dryer heating element. But how does a loose connection produce heat?
Electrical connections need to be mechanically tight to ensure that the resistance across that connection is as low as possible, ideally 0 ohms. When a connection becomes either loose or corroded, it develops resistance. This resistance dissipates power in the form of heat when current flows through it. Even a resistance as low as 5 ohms can produce more than enough heat to burn up the connection and surrounding wires.
In this little video, I show you the effects of a loose connection in a circuit and we'll see how much heat, in watts, a typical loose connection produces. I'm also going to dispel a common myth that I hear, even from manufacturers: loose connections cause a circuit to draw more current. This is completely false and I'll prove it to you.
- Upcoming webinar on Schematic-foo: ancient Samurai art using tech sheets as deadly weapons in appliance repair. Get the details here!
- Appliance product training today: we don't need hands-on, we need brains-on. The future is here NOW!
- Bidness Talk: Pricing your services; fixed and variable costs; how much should you be charging for repairs? Strategic customer selection and when to fire your customer; Property managers: the scourge of the appliance repair industry?; Getting paid for your service.
- Troubleshooting: what it is and what it is not. Recognizing when you don't have enough information to make an analytical diagnosis.
- De-bunking another electric circuit myth... this time promulgated by a manufacturer. Using Ohm's Law to analyze the effects of high resistance/loose connections on a circuit using an electric oven bake circuit as an example.
- We're back from our bidness trip last week but Mrs. Samurai has a cold so this episode is mostly Tech Talk.
- Visit to American Appliance in Golden, CO, one of Sub-Zero's premiere partners.
- Recap of Dacor training in their Android-controlled ranges
- GFCIs and AFCIs. What they are, what they do, how they're different, and current NEC requirements.
- Voltage and current in series and parallel circuits.
- Samurai and Son of Samurai are off to Dacor training.
- Manufacturers focusing on producing higher-profit upscale major appliances and what this means for your service business
- Sub-Zero doing a huge expansion in Wisconsin to crank out upscale dishwashers and ranges. What are these manufacturers seeing that you should also be seeing as an appliance repair company?
- A recent Samsung warranty debacle shows how there’s a greater need for skilled appliance technicians but the trade is still “ate-up” with parts changing monkeys.
- Voltage sag re-visited.
- 120/240 VAC, three-wire, single-phase electric service vs. 120/208 VAC, four-wire, three-phase electric service. Samurai explains the difference between these two common types of electric service and gives some examples of how some appliances are equipped and labelled to work with either service. Link to a Samurai video that explains 120/240 VAC split-phase household service: https://youtu.be/zs4HjHhf0x8
- Customer selection: Do you pick and choose your customers? Why or why not? We talk about a recent topic at the tech-only forums at Appliantology where this subject came up. [Link to forum topic, must be logged in and a tech member at Appliantology to read it: http://appliantology.org/topic/55055-general-question-for-stovetop-wiring/]