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    • Samurai Appliance Repair Man

      Webinar Recordings Index Page   03/02/2018

      On-demand appliance repair training videos for Professional Appliantologist members Over 30 hours (and growing!) of original, high quality appliance training webinars developed and given by yours truly are at your fingertips, on topics you won't find anywhere else. Fill in those knowledge gaps, strengthen those areas of uncertainty, and boost your skills. Watch on mobile or desktop at your convenience whenever, wherever.  Ultra Short Primer on Basic Electricity, Circuits, Ohm's Law, and Schematic Reading (Length: 1:04:48) Basic Refrigerator Troubleshooting (Length: 1:10:45) Schematic Reading Workshop, 10/2015 (Length 1:19:08) Troubleshooting Strategies for Computer-Controlled Appliances (Length: 48:34) Semiconductors and PN Junctions (Length: 1:04:37) Appliance Temperature Sensing Devices & Technology (Length: 1:27:33) Voltage Measurements, Meters, Ghost Voltages, and Triac-controlled Neutrals (Length: 1:29:32) Troubleshooting with Tech Sheets, Part 1, 4/2016 (Length: 1:09:26) Troubleshooting with Tech Sheets, Part 2, 4/2016 (Length: 1:21:11) Tech Sheet Review, 4/9/2016: Bosch Speed Cooker, Amana Refrigerator, GE Glass Cooktop Range (Length: 1:22:58) Pulse Width Modulated (PWM) Switches used in Samsung Switched Mode Power Supplies (SMPS) (Length: 27:07) PWM Computer Cooling Fan in a Whirlpool Refrigerator (Length: 14:53) Understanding AC Split-phase Household Power Supplies (Length: 52:41) Troubleshooting a Samsung Electric Dryer without Disassembly using Live Tests and the Schematic (Length: 22:47) Troubleshooting a Bosch Dishwasher No-Heat Problem using the Schematic and Live Tests (Length: 15:38) Linear Motors and Linear Compressors (Length: 55:54) Bi-directional PSC Drive Motor Systems in Whirlpool VM Washers (Length: 56:52) Appliance Service Call Structure and Troubleshooting Strategies (Length: 1:00:16) The Ten Step Troubleshooting Tango and Workshop Exercises (Length: 1:35:39) Troubleshooting Ten-Step Tango Advanced Workshop (Length: 1:32:06) Ten-Step Tango Troubleshooting Workshop: Refrigerators (Length: 1:35:57) Whirlpool Duet Washer Schematic Analysis & Whirlpool Dryer Moisture Sensor System (Length: 1:03:04) Neutral Vs. Ground, Inverter Microwave, Digital Communications, Loading Down in DC loads, and more! (Length: 1:14:45) Gas Oven Service Call After a Parts Changing Monkey (Length: 36:04) AFCI and GFCI Circuit Protection Technology (Length: 41:26) Troubleshooting Samsung Refrigerators and more (Length: 1:29:58) 3-way Valves and Dual Evaporator Refrigerators (Length: 1:15:45) Split-Phase Compressors and PTC Start Devices (Length: 1:11:57) Gas Dryer Ignition Systems (Length: 53:50) Refrigerator Sealed System Thermodynamics, Part 1 (Length: 43:07) Refrigerator Sealed System Thermodynamics, Part 2 (Length: 1:09:09) Refrigerator Sealed System Thermodynamics, Part 3 (Length: 1:11:56) Refrigerator Sealed System Thermodynamics, Part 4 (Length: 37:45) Refrigerator Sealed System Thermodynamics, Part 5 (Length: 16:35) Appliantology Peer Group web meeting, Feb 25, 2018 (Length: 1:47:30) Appliantology March 2018 Peer Group Meeting (Length: 1:59:58) To access these webinars and all the other info-goodies here at Appliantology, become a Professional Appliantologist today. If you need cost-effective, time-flexible, state-of-the-art appliance technical training, check out the Master Samurai Tech Academy.
    • Son of Samurai

      [Webinar] Appliantology Peer Group   04/24/2018

      Bring something you'd like to share with your brethren in the craft: it could be photos, a tech tip, new insights gleaned from recent training -- anything having to do with the business or technical sides of the appliance repair trade. If you've got something to show, we'll let you share your screen and give you the opportunity to teach us all something new. And of course, Team Samurai will be there to answer any questions you might have about how to use Appliantology.  

Samurai Appliance Repair Man's Blog

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Troubleshooting a microwave oven using the Divide and Conquer Method

Samurai Appliance Repair Man

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Electrically speaking, microwave ovens have two sections: low voltage and high voltage. The low voltage section consists of the door switches, start button, control panel, turntable motor, cooling fan, stirrer motor, and some miscellaneous switches. The high voltage section consists of the transformer (which steps 120vac line voltage in residential units and 240vac in some commercial units up to 2,000+ volts), the high voltage rectifier (diode), and the charging capacitor (which together with the rectifier doubles the output of the HV transformer), and the star of the show, the magnetron. You can see pictures of all these parts and where they're located in typical microwave ovens in these spiffy, interactive diagrams:

Detailed Countertop Microwave Oven Diagram

Detailed Built-in Microwave Oven Diagram

Lots of times, when you're troubleshooting a microwave problem, it's helpful to figure out early on whether the problem is in the low voltage section or the high voltage section because this narrows the problem down considerably. Professional Appliantologists call this the Divide and Conquer Method of Troubleshooting and it is a very powerful technique indeed. At this point, I'll turn it over to Academy Fellow Budget Appliance Repair (Willie), Professor Emeritus of Appliantology, to explain this sublime troubleshooting kata:

One way to test this is to remove the ?black (L1) power wire from the high voltage transformer, or both wires going to the the primary 110 volt side of the high voltage transformer if you can't figure out which is the line and which is neutral, (be sure to tape them safely away from touching anything).

Then turn the microwave on and it should startup and count down and cooling fan should run, just won't do any heating, (by disconnecting the high voltage transformer you have completely eliminated the high voltage system from the picture). If this works OK then you know the switches and complete control circuit is OK.

If the test with the high voltage system disabled above works, next reconnect the transformer and disconnect the two wires going to the mag tube, (make sure to mark the terminals they come off of), and make sure they are safely away from everything and give it another try. If again it works without blowing the fuse you can be pretty sure you have a bad mag tube, even if it doesn't show as a directly shorted mag tube when checking continuity from the terminals to the mag tube case.

After you've applied the Divide and Conquer Method to figure out what's wrong with your microwave oven, you can buy the parts with a 365-day return policy here ==> http://www.repaircli...rts?RCAID=24038

Source: GE Spacesaver JVM1441BH04 Microwave continually blows fuse after slamming door