The invention claimed is:1. A method of operating a plurality of inductive loads, which can be connected parallel to one another between first and second terminals, to which a controllable voltage is applied, the method comprising:detecting a connection of a previously non-energized load to the terminals;setting the voltage to a predetermined first value;adjusting the voltage, after lapse of a first predetermined time interval, to a predetermined second value, with the second value being lower than the first value; anddetermining one of the first and the second values on a basis of an electrical resistance between the terminals.2. The method according to claim 1, further comprising adjusting the voltage, after a further predetermined time interval, to a predetermined third value with the third value being lower than the second value.3. The method according to claim 1, further comprising, in relation to a plurality of loads switched on at intervals, always setting the voltage to a highest of the first and the second values.4. The method according to claim 2, further comprising, if no load is connected to the terminals, reducing the voltage to a fourth predetermined value which is lower than the third predetermined value.5. The method according to claim 1, further comprising determining the electrical resistance on a basis of the voltage applied at the terminals and a current flowing through the terminals.6. A method of operating an inductive load which can be connected between first and second terminals to which a controllable voltage is applied; the method comprising:detecting a connection of a previously non-energized load to the terminals;setting the voltage to a predetermined first value;adjusting the voltage, after lapse of a first predetermined time interval, to a predetermined second value, with the second value being lower than the first value;adjusting the voltage, after a further predetermined time interval, to a third value, with the third value being lower than the second value; anddetermining one of the first and the second values on a basis of an electrical resistance between the terminals.7. A device for operation of a plurality of switchable inductive loads between first and second terminals, the device comprising:a half-bridge for applying a predetermined voltage between the terminals;a control device being designed for controlling the half-bridge such that a predetermined voltage is applied between the terminals;the loads being connectable in parallel with one another between the first and the second terminals; andthe control device being designed to set the voltage between the terminals to a predetermined first value, when a previously non-energized load is connected between the terminals, and, after lapse of a predetermined time interval, to reduce the voltage to a predetermined second value which is lower than the first value.8. The device according to claim 7, wherein the control device is also designed to reduce the voltage between the terminals, after the lapse of a further predetermined time interval, from the second value to a third value in which the third value is lower than the second value.9. The device according to claim 7, wherein the half-bridge comprises a first current control valve for connecting the first terminalto a high potential of an intermediate circuit voltage and a second current control valve for connecting the first terminal to a low potential of the intermediate circuit voltage (135), and the control device is designed to actuate the first and the second current control valves by turns in order to set the predetermined voltage.10. A device for operating a switchable inductive load between first and second terminals, the device comprising:a half-bridge for applying a predetermined voltage between the terminals;a control device designed for actuating the half-bridge in such manner that a predetermined voltage is set between the terminals; andthe control device is designed to set the voltage between the terminals to a predetermined first value, when a previously non-energized load is connected between the terminals, and, after lapse of a predetermined time interval, to reduce the voltage to a predetermined second value which is lower than the first value, and, after lapse of a further predetermined time interval, to reduce the voltage from the second value to a third value in which the third value is lower than the second value.
