| 摘要 |
The invention relates to a circuit arrangement for deenergising DC-energised magnet coils. It is used especially in the case of electromagnetic switching apparatuses. In this circuit arrangement, a deenergising path (diodes 5, 7) is connected to the magnet coil (14). An electronic switch (field-effect transistor 13), which is connected in series with the magnet coil (14), is connected as a function of the energising. A voltage-dependent resistor (17) on which the current which flows through the magnet coil (14) is commutated when the electronic switch (13) is switched off is connected to the electronic switch (13). An adjustable resistor (26) is connected in parallel with the voltage-dependent resistor (17), as a result of which the opening delay can, if required, be lengthened such that it can be adjusted beyond its minimum value. <IMAGE>
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