Comparison of temporary electromagnet and permanent magnet

Same point

Both permanent magnets and electromagnets can be manufactured to produce different forms of magnetic fields.

Difference

When choosing a magnetic circuit, the first consideration is what you need the magnet to do. Permanent magnets are dominant in situations where electricity is inconvenient, frequent power failures, or where there is no need to adjust the magnetic force. For applications that require changing the magnetic force or requiring remote control, electromagnets are useful. Magnets can only be used in the originally intended way. If the wrong type of magnet is applied to a special purpose, it may be extremely dangerous or even fatal.
Advantages of permanent magnets
Many machining operations are performed on heavy bulk materials, and these applications require permanent magnets. Many users of machinery factories believe that the biggest advantage of these magnets is that they do not require electrical connections.
The permanent magnet features a lifting capacity of 330 to 10,000 pounds, and it only needs to rotate a handle to connect or disconnect the magnetic circuit. The magnet is generally equipped with a safety lock to ensure that the magnet will not accidentally disconnect when lifting. Magnet sets can be used for long loads that are relatively heavy and cannot be handled by a single magnet.

Advantages of electromagnets

In many cases, the parts to be processed are very thin (0.25 inches or smaller) and must be extracted from a pile of similar parts. Permanent magnets are not suitable for work that only picks up one part from a pile of parts at a time. Although permanent magnets are extremely reliable when used correctly, they cannot change the magnitude of the magnetic force. In this regard, the electromagnet allows the operator to control the strength of the magnetic field through a variable voltage control device, and can select one piece from the stacked parts. Self-contained electromagnets are the most cost-effective magnets in terms of unit lifting capacity, and their lifting capacity can be extended to 10,500 pounds.
Magnets powered by batteries are useful. They use self-contained gel batteries to increase lifting capacity and can handle flat, round, and component-shaped products. The magnet powered by the battery can repeatedly complete the lifting action, providing considerable lifting capacity without an external power supply.
Summary: Permanent magnets and temporary electromagnets have their own advantages and disadvantages. When choosing a magnet, we should choose a suitable magnet according to the characteristics and convenience of our products.