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View Full Version : Electrical parameters / troubleshooting - Appliance tip of the week...



jeff1
04-16-2013, 01:43 AM
Appliance tip of the week...

You will most commonly measure two electrical parameters when you're troubleshooting your appliance: resistance ( measured in units called "ohms") and voltage. Typically, both of these measurements are made on a single meter called a multi-meter, which you can set to measure either ohms or voltage ac.

Figure 1 shows how to measure resistance. Resistance ( or continuity ) is measured in units called "ohms." You'll commonly want to know the resistance of things like bake elements and solenoid coils. For example, a good bake element typically has a resistance of about 30 ohms. If your oven's not baking and you measure the resistance of the bake element and the meter doesn't move, then you know you have a bad element. Everyone is looking to save money, from coupons to tax deductions, so finding out if a repair is possible before you buy a whole new unit can be a great way to save. A simple ohm measurement can save a lot of money :)

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Some helpful tips for volt and ohm testing...

Ohm: When ohm ( continuity ) testing a switch, thermostat, element, etc, you will need to isolate the item by removing the wires to that item so you can properly ohm test it...( write down what wire goes where first! ) This does not happen often, but sometimes a switch can ohm ok but still fail when real power is supplied to it. R X 1 is a good scale to start out with when doing some ohm / continuity testing.

Volt: Be careful!! Volt testing should be done across a switch, thermostat, fill valve (Figure 4), etc...for example - a volt test across a dryer thermostat - a reading of 220-240 volts AC across the thermostat leads is an open circuit / thermostat...a reading of 0 ( zero ) is a closed circuit / thermostat. A reading of 220-240 volts AC across the two wires to a bake element and no heat from the element is a bad element.

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259 Volts AC 750 , Volts DC 1000, Amps AC 10, Resistance max. (Ohms) 2M, Continuity, Temperature -4 ?F to 2498? F, Display (Counts) 2,000, Operating Temperature 32? F to 74? F (0?C to 23?C), Fuse Protection mA: 0.2A/ 250V, Power 9 V Battery (included), Size 5.5"L x 3"W x 1.5". Temp probe included. (http://www.repairclinic.com/referral.asp?R=153&N=964740)

260 This compact multitester is capable of making most electrical measurements and testing continuity. Essential for analyzing malfunctions in appliances including motors, heating elements and thermal fuses. (http://www.repairclinic.com/referral.asp?R=153&N=241764)

jeff.