How to Judge Whether a Motor Has a Copper Core or an Aluminum Core From the Outside?

Nowadays, most electrical appliances use aluminum core wires instead of copper core wires. In particular, more electrical equipment such as motors and transformers are made with an aluminum core wire instead of a copper core.

How do you tell whether a motor has a copper or aluminum core?

1. Price. Products of the same model, such as aluminum-core motors, or transformers,s are far cheaper than copper-core ones; hence, they are economically viable for users to buy.

2. Volume. Motors or transformers of the same model made of an aluminum core are much bigger compared to copper core ones. This is because, in the case of using an aluminum core, it is necessary to increase the cross-sectional area of the conductors; therefore, its volume increases.

For example, a YR160M-4 7.5KW motor has 36 slots in total. For each slot, 34 turns of 1.50 diameter copper wire are needed. If using aluminum wire, the diameter needs to be increased to meet the current carrying capacity of the 1.50 diameter copper wire. Take the motors of washing machines as examples. Generally, motors wound with aluminum wire are about 20% to 30% larger than motors wound with copper wire, and silicon steel sheets are also thicker than motors wound with copper wire.

3. Weight. For motors with the same power, the aluminum core is lighter than the copper core because the density of aluminum is lower than copper.

4. Temperature rise: when motors of the same power are powered on, the temperature of aluminum is slightly higher than that of copper. The longer the time, the more obvious the difference is. So, from the perspective of load, copper is better than aluminum.

5. Nameplate: Regular motor manufacturers will indicate on the motor: This motor is wound with aluminum wire and complies with the national LSO900# standard. The original motor will be stated on the nameplate. The aluminum wire winding will be marked with L or m, but the copper wire will not be marked.