Reduced performance can have electrical and mechanical causes. Possible factors include winding or insulation damage, faulty connections, an unsuitable power supply, elevated temperatures, or changes to contact surfaces and air gaps. The material being lifted and the operating conditions also affect the effective force. Therefore, we test the magnet, power supply, and application together.

Rewinding is necessary when the existing winding or insulation is so damaged or aged that a local repair is no longer a reliable solution. This is based on electrical tests, visual condition, thermal traces, and the mechanical structure. We also consider whether the cause lies outside the winding. This prevents replacing an intact winding or overlooking consequential damage.

The scope of testing depends on the design, extent of the repairs, and application requirements. We check the relevant electrical parameters, the insulation, and the mechanically repaired areas. Depending on the order, functional or acceptance tests supplement the assessment. Before use, the application-specific safety and operator requirements must also be considered.

Rebuilding is a viable option when replacement parts are no longer available, existing interfaces must be retained, and the application requirements can be clearly defined. We record geometry, electrical data, duty cycle, load case, and environmental conditions. Safety and operational requirements must be explicitly incorporated into the design and acceptance testing.