Abstract: According to an example aspect of the present invention, there is provided an apparatus for magnetically attaching to a load comprising: a direct current power source; an electromagnet comprising a coil connectable to the direct current power source for feeding current to the coil for attaching to a load by a magnetic force; a current measurement device connected to the coil; a user interface for displaying information indicating a load capacity of the apparatus; and a controller operatively connected to the direct current power source, the coil, the current measurement device and the user interface to cause: connecting the direct current power source to the coil; measuring current of the coil; determining a rise time of the current to a nominal value of current of the coil, when the load is attached to the apparatus; determining a load capacity and/or usage level of the load capacity of the apparatus based on the rise time of the current to the nominal value; and displaying the load capacity on the user inte