Introduction This blog shows you how to test Zener diodes using a multimeter and a few items that are commonly found around the house or workbench. Safety Although the voltages used in the tester we’ll use are relatively low, know that voltages in excess of 30 volts can be a safety issue under the right […]
This blog provides a comprehensive review of the Fluke 116 Multimeter along with the theory behind multimeter usage and operation. About the Fluke 116 Multimeter The Fluke 116 digital multimeter was designed for Field Technicians. It has many functions that are relevant to HVAC, appliance repair, and other like disciplines. Here is a list of […]
Introduction If you get the the expected “S” during a Whirlpool Refrigerator Jazz Board model’s defrost system diagnostic mode, and it changes to the dreaded “O” after only a minute or two, you likely have “ohmic self-heating” of the bimetal thermostat. What is Ohmic Self-Heating? Ohmic self-heating is based on the concept of “ohmic heating”, […]
A “ghost voltage” is an electrical potential that appears on an undefined conductor due to capacitive coupling via proximity to other conductors or by electromagnetic induction. A ghost voltage has almost no ability to source any current and may simply disappear if any kind of a load is connected to it. Further, a ghost voltage […]
Introduction Wouldn’t it be great to have a battery that could supply an infinite current? Your flashlight could run on AA batteries, yet have infinite brightness! You could start a car with a standard 9v battery! Such batteries would be “ideal” voltage sources. Now, enter reality. What is a Voltage Source? A voltage source is […]
What is an H-Bridge? Conceptually, an H-Bridge is just an arrangement of 4 switches configured in such a way as to reverse the polarity of a load. For example, closing switches S1 and S4 will result in a positive polarity to the left of the motor (M). Instead, closing switches S2 and S3 will reverse […]
Frequently Asked Questions about Equivalent Resistance is another in a series of FAQS about electricity and electronics that are oriented toward Appliance Technicians and HVAC Technicians. Frequently Asked Questions about Equivalent Resistance Q. What is the equivalent resistance of two resistors in series?A. It is the sum of the two resistors’ values. Q. What is […]
Frequently Asked Questions about Capacitor Replacement is another in a series of FAQS about electricity and electronics that are oriented toward Appliance Technicians and HVAC Technicians. Important Note Never attempt to repair circuit boards in appliances or HVAC systems unless you are directly supervised by a licensed professional engineer and doing so under approved ISO […]
Below is the full list of frequently asked questions about electricity and electronics, developed specifically for Appliance and HVAC technicians. Basic Circuit FAQS – CLICK HERE BLDC Motor FAQS – Coming soon Capacitor FAQS – CLICK HERE Capacitor Replacement FAQS – CLICK HERE ESR (Equivalent Series Resistance) FAQS – Coming soon Equivalent Resistance FAQS – […]
Frequently Asked Questions about Inductors is another in a series of FAQS about electricity and electronics that are oriented toward Appliance Technicians and HVAC Technicians. Frequently Asked Questions about Inductors Q. What is an inductor?A. It is an AC device that stores electrical energy in the form of a magnetic field. Q. How is an […]