How does an SMPS Power Supply Work?

In this article, we’ll go into detail, how an SMPS or Switched Mode Power Supply works on a control board. We’ll talk about how the input filter works, initial rectification or conversion of AC into DC voltage, the switching circuit, high frequency transformer and galvanic isolation, feedback control circuit, and output rectification and filter. We’ll […]

Testing Diodes with a Multimeter

Introduction In this blog, we will describe what diodes are, how they function, and how to test them. We will identify two of the most common types of diodes encountered by Technicians, and describe how to test them in circuit and out of circuit. Additionally, we will discuss the most common ways that diodes fail […]

Four ways Ohms can Lie

What does it mean when we say “Ohms can Lie”? It’s more of a colloquial expression suggesting that relying on static resistance may not give you enough information about how some components behave when energized. For example, when you measure the resistance of a component, and its “opposition to current flow” varies when subjected to […]

ESR Lookup Table Cheat Sheet

This page serves as a quick reference for Field Technicians when measuring electrolytic capacitor Equivalent Series Resistance (ESR) when using the Atlas ESR 70 meter. For electrolytic capacitors there are typical ESR values associated with particular capacitances. When measuring ESR in the field, this helpful reference table will facilitate easy lookup so that you can […]

How does a Control Board Work?

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 and UL processes. Be sure to subscribe to our Youtube Channel! For tons of videos on electrical and electronics diagnostics, practical electrical theory, and field-technician resources, […]

Samsung Dryer HC Error – Solved

Introduction This is an actual case where a Samsung dryer was shutting down after a few minutes and displaying an HC error code. Samsung “Overheating” Error Codes The HC error code means that the dryer reached a temperature threshold that it was either not designed for or that is unsafe. Here are some of the […]

Samsung Dryer HE Error – Solved

Introduction This is a case history of how a Samsung electric dryer that was displaying an HE error code, was successfully diagnosed and repaired. The reader is assumed to be an Appliance Technician that is familiar with safety practices when working with appliance. Appliance have voltages levels within them that can be harmful or lethal […]

Testing Zener Diodes with a Multimeter

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 […]

Fluke 116 HVAC Multimeter Review and Theory of Operation

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 […]