Introduction One question I’ve been asked many times in this business is whether a 240v electric appliance can be used on a 208v electrical system. Some apartment buildings use what’s known as 3-phase power, as opposed to the more commonly used single split-phase configuration that comprises the vast majority of residential electric power. This blog […]
Introduction This blog will introduce the many ways that an NCV voltage pen can be used to diagnose electrical circuits. In fact, you might be surprised as to how versatile and useful the voltage pen can actually be. I’ll show you how this simple device can be used to detect Ghost Voltages, detect Compromised Voltage […]
What do floating neutrals, gas dryer valve circuits, Whirlpool electric dryer cool-down circuits, loose terminal block connections, shorted elements, and failing relay contacts all have in common? As the title of this articles suggests – the ever-present voltage divider. They’re everywhere and reside in multiples in every appliance you encounter. They’re not only present in […]
Introduction This quiz is designed to help Appliance technicians learn, test their knowledge, or just provide a review of their existing knowledge of electrical theory as it applies to appliance repair. Each question will have an associated answer – helping solidify your knowledge of electricity. So let’s test your knowledge. How Many Questions can you […]
The title says it all. A voltage pen can be much handier than some Technicians realize. Yes, they can be easily used to locate an open or loose (compromised) neutral in in a voltage source. THIS BLOG IS INTENDED FOR APPLIANCE TECHNICIANS ONLY. ALWAYS USE APPROPRIATE SAFETY PRECAUTIONS WHEN WORKING WITH ELECTRICITY. About Neutral Neutral, […]
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 […]
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 […]
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 […]
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 […]
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. Anatomy of a Control Board In this article, I’ll do a detailed walkthrough of a common refrigerator control board – the WR55x10942, go […]