What’s the Difference Between 208v and 240v?
The easy answer is 32v. Class dismissed. I’m only joking, of course. Finding the difference between 208 and 240v power supplies may sound quite simple, but there are some pretty sharp fundamental differences. Apart from the obvious differences in overall voltage, 208 and 240v power supplies use the electrical company’s power differently and the motors […]
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3 Phase Motors – The Basics
Fundamentally, three-phase, alternating current motors are about as simple as a motor gets. The power company produces three phases by spinning magnets and then on the other end we produce electromagnets that spin the motor according to the same 60 cycles per seconds frequency (60hz). All three-phases are 120-degrees out of phase from one another […]
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Using Power Factor to Check Capacitors Under Load
Capacitors are traditionally tested with a capacitance meter (commonly found as a function within a multi-meter) with the component taken completely out of the circuit. “Bench testing”, as this method is referred to, is hands down the safest method of checking capacitance in micro-farads. All other methods require the capacitor to be wired into the […]
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Isolation Diagnosis
There are many great diagnostic tools available to the service technician today, but I shaven't found a tool as versatile than the simple isolation diagnosis. There are many ways this concept can be applied but let's start with some examples so you get what I mean. Low Voltage Short Circuit Isolation Diagnosis You arrive on […]
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Parallel Circuit Resistance 
In a Series circuit (loads connected in a row end to end), it's easy to calculate total circuit resistance because you simply add up all the resistances to get the total. In a Parallel circuit, the voltage is the same across all the loads; the amperage is simply added up, but the resistance is a […]
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Ohms/Continuity Basics
Some quick basics – An ohmmeter is used to measure the resistance to electrical flow between two points. The ohmmeter is most commonly used to check continuity. Continuity is not a “measurement” as much as it is a yes/no statement. To say there is continuity is to say that there is a good electrical path […]
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Something You May Want to Consider on Every Call
There are a few important things that I suggest checking on every service call to reduce callbacks and increase customer satisfaction. One of them that often gets missed is preventing wire rub-outs. One of my area managers and experienced tech Jesse Claerbout shot a video showing the simple step he takes to prevent major damage. […]
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