Method and apparatus for handling contactor / relay contact bounce under transient conditions

A circuit arrangement capable of reducing contact bounce in a contactor resulting from a transient condition, the circuit arrangement comprising:

• a contactor having a first magnetic coil electrically connected to a second magnetic coil, one or both of the coils configured to close contacts when power is to be provided to a load, the first magnetic coil generating a higher magnetic field than the second magnetic coil;
• a switch configured to selectively electrically short the second coil to allow the first coil to generate the higher magnetic field;
• a voltage sensor configured to detect voltage fluctuations caused by the transient condition, the voltage sensor having an output used to selectively activate a timer, which in turn activates the switch for a selectable period of time to thereby energize the first coil to generate the higher magnetic field;
• and
• wherein the first coil includes a pull-in coil and the second coil includes a hold coil, the pull-in coil and the hold coil being connected in series.

A circuit arrangement capable of reducing contact bounce in a contactor resulting from a transient condition, the circuit arrangement comprising:

• a contactor having a first magnetic coil electrically connected to a second magnetic coil, one or both of the coils configured to close contacts when power is to be provided to a load, the first magnetic coil generating a higher magnetic field than the second magnetic coil;
• a switch configured to selectively electrically short the second coil to allow the first coil to generate the higher magnetic field;
• a voltage sensor configured to detect voltage fluctuations caused by the transient condition, the voltage sensor having an output used to activate a pulse width modulator have a selectable duty cycle, an output of the pulse width modulator selectively activating the switch on and off according to the duty cycle to thereby energize the first coil to generate the higher magnetic field;
• and
• wherein the first coil includes a pull-in coil and the second coil includes a hold coil, the pull-in col and the hold coil being connected in series.

A method of reducing contact bounce in a contactor resulting from a transient condition, the method comprising the following steps:

• utilizing a contactor having a first magnetic coil electrically connected to a second magnetic coil, one or both of the coils configured to close contacts when power is to be provided to a load, the first magnetic coil generating a higher magnetic field than the second magnetic coil;
• selectively operating a switch configured to selectively electrically short the second coil to allow the first coil to generate the higher magnetic field;
• utilizing a voltage sensor configured to detect voltage fluctuations caused by the transient condition, the voltage sensor having an output used to selectively activate the switch to thereby energize the first coil to generate the higher magnetic field;
• and
• wherein the first coil includes a pull-in coil and the second coil includes a hold coil, the pull-in coil and the hold coil being connected in series.

A method of reducing contact bounce in a contactor resulting from a transient condition, the method comprising the following steps:

• utilizing a contactor having a first magnetic coil electrically connected to a second magnetic coil, one or both of the coils configured to close contacts when power is to be provided to a load, the first magnetic coil generating a higher magnetic field than the second magnetic coil;
• selectively operating a switch configured to selectively electrically short the second coil to allow the first coil to generate the higher magnetic field;
• utilizing a voltage sensor configured to detect voltage fluctuations caused by the transient condition, the voltage sensor having an output used to selectively activate a timer, which in turn activates the switch for a selectable period of time is thereby energize the first coil to generate the higher magnetic field;
• and
• wherein the first coil includes a pull-in coil and the second coil includes a hold coil, the pull-in coil and the hold coil being connected in series.

A method of reducing contact bounce in a contactor resulting from a transient condition, the method comprising the following steps:

• utilizing a contactor having a first magnetic coil electrically connected to a second magnetic coil, one or both of the coils configured to close contacts when power is to be provided to a load, the first magnetic coil generating a higher magnetic field than the second magnetic coil;
• selectively activating a switch configured to selectively electrically short the second coil to allow the first coil to generate the higher magnetic field;
• utilizing a voltage sensor configured to detect voltage fluctuations caused by the transient condition, the voltage sensor having an output used io activate a pulse width modulator having a selectable duty cycle, an output of the pulse width modulator selectively activating the switch on and off according to the duty cycle to thereby energize the first coil to generate the higher magnetic field;
• and
• wherein the first coil includes a pull-in coil and the second coil includes a hold coil, the pull-in coil and the hold coil being connected in series.