Thermal Overload Relay Testing

The bimetallic strip gets heated up by the current directly or indirectly and when the current flow exceeds the set value it bends.

Thermal overload relay testing.

It is placed in the motor circuit in such a way that the current to the motor flows through its poles. Overload relay working principle thermal overload relay thermal overload relay construction working and application. How to set thermal overload relay. In this post i will complete guide you about how to test a refrigerator thermal overload protector using a multimeter.

The overload class 10 20 30 is supposed to be the time in seconds that the relay operates at 500 of rated. A thermal overload relay works in the principle of electro thermal properties in a bimetallic strip. Dishwasher thermal overload switches can usually be found behind the bottom toe panel. What procedure can be used to test the phase loss or overload protection on a cep7 overload relay.

We need to setting the value of overload relay properly depend on our application and motor full load ampere if we setting low from fla it can cause motor trip c0ntinues and process not running smoothly. Today i am writing about the refrigerator overload protector testing using multi meter. Note that some appliance panels are held in place with small metal clips. Remove the screws that hold the panel in place to free it.

Anything more specific would have to be furnished by the relay manufacturer as a model dependent time current characteristic curve or band as the case may be. In case of thermal bymetalic relay. Locate the thermal overload switch behind the bottom toe or back panels of most residential clothes washers or dryers. Say relay0 625 1 ampere range set at1 ampere.

Apply3 phase load or current as1 2 ampere 1 3 ampere 1 5 ampere relay point95 96 will take changeover from nc to no another relay point97 98 will changeover from no to nc generally relay was set considering130 140 overload. Literature technical tips faqs cep7 overload relay test procedures. As you know that thermal overload protector is designed to protect the refrigerator compressor during over current flow. Thermal overload is widely used for.

Our normal production test procedure is not something that a customer could easily duplicate however a basic on site test can be run following the examples below.