Posts By: Scott Brown

Master Samurai Tech Radio, Episode 12 [Special Video Edition]

Posted on October 30, 2015 by - MST Radio

 

podcast1 200Industry Talk:
- BSH- what's the "H" stand for?
- Charge your smart phone from your refrigerator *wirelessly* with WattUp technology.

Master Samurai Tech news:
- New post on how loose electrical connections, like splices and terminals, can produce enough heat to burn wires and insulation. http://mrappliance.mastersamuraitech.com/loose-electrical-connections-and-heat/
- Recapping the dismal and outdated state of appliance repair training today. YouTube makes hands-on disassembly training obsolete. What we need today is BRAINS-ON training! Learning the theory of operation and the underlying technology in modern appliances today so you can figure out weird problems without relying pattern recognition (if this problem, replace that part). Real technicians today are skilled in the lost art of troubleshooting: following a cause and effect chain of reasoning to its logical conclusion and identifying the defective component that is no longer operating within specifications.

Business Talk:
- How to handle those tricky service calls where there was no problem found.

Tech Talk:
- Troubleshooting scenario: electric dryer element not getting hot. Good power supply. Known good element. Element connected: have 120vac from each end (L1 and L2) to N, but 0vac across the element terminals. What conclusion can you draw? Voltage vs. voltage drop; 120/240 single phase-split phase household electrical power supplies; loads in series.

Master Samurai Tech Schematic Lab Webinar 10-22-2015

Posted on October 24, 2015 by - Academy Talk, Tech Talk

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 and Heat

Posted on October 23, 2015 by - Tech Talk

Burnt Electrical Splices in a Junction BoxLoose 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.

 

 

Master Samurai Tech Radio, Episode 11

Posted on October 17, 2015 by - MST Radio

podcast1 200- 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.

Master Samurai Tech Radio, Episode 10

Posted on October 9, 2015 by - MST Radio

podcast1 200- 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.