CN1985548A - Electronic ballast protection - Google Patents

Abstract

A method of electronic ballast protection including providing an electronic ballast having an AC/DC converter 104 with an electronic ballast input and a mains voltage connection 103 connectable to a mains voltage 102, an inverter 120 operably connected to the AC/DC converter 104 and having an electronic ballast output 125 connectable to a lamp 124, a control circuit 116 controlling the inverter 120, and a low voltage power supply 114 providing low voltage power to the control circuit 116; supplying power to the low voltage power supply 114 from the electronic ballast input when the mains voltage connection 103 is wired to mains voltage 102; and disconnecting the power to the low voltage power supply 114 when the electronic ballast output 125 is wired to the mains voltage 102.

Description

Electronic ballast protection

The present invention relates generally to lighting systems, and more particularly to electronic ballast protection.

Gas discharge lamps such as fluorescent and high intensity discharge (HID) lamps require ballasts to limit the current to the lamp. Electronic ballasts have become increasingly popular due to their many advantages. Electronic ballasts offer greater efficiency - 15% to 20% more than magnetic ballast systems. Electronic ballasts generate less heat, reduce cumulative cooling load, and operate more quietly without "hum". In addition, electronic ballasts provide more design and control flexibility.

Figure 1 is a schematic diagram of an exemplary electronic ballast circuit for a HID lamp. The electronic ballast 100 receives a mains voltage 102 at a mains voltage connection 103 and converts the mains voltage 102 to a DC bus voltage on a DC bus 112 using an AC/DC converter 104 . The AC/DC converter 104 comprises an EMI filter 106, a diode bridge 108 connected to said EMI filter 106 at an EMI filter-diode bridge connection 107 and a diode bridge-DC/DC converter connection 109 connected to The DC/DC converter 110 of the diode bridge 108 . A low voltage power supply 114 is connected to the DC bus 112 and provides low voltage power to the control circuit 116 . A control circuit 116 comprising a microprocessor 118 controls an inverter 120 comprising MOSFETs S1, S2, S3, S4 and a filter circuit 128 comprising an inductor and a capacitor. MOSFETs S1 , S2 , S3 and S4 are switched to convert the DC bus voltage on DC bus 112 to output power on electronic ballast output 125 . Electronic ballast output 125 powers lamp 124 . A resonant circuit 126 comprising a resonant inductor LR and a resonant capacitor CR is connected across the electronic ballast output 125 to provide the high ignition voltage required to start the lamp 124 . Those skilled in the art will understand that various topologies, such as half-bridge inverters, can be used for the electronic ballast circuit and the resonant circuit.

A particular challenge is protecting electronic ballasts during installation and start-up. Electronic ballasts include electronic components that can be damaged by high currents if the electronic ballast is miswired during installation. Other electronic ballast components fail over time from ignition of the lamp due to temperature and thermal stress.

Currently, the correct wiring of electronic ballasts depends on the skill and care of the installer. The location of the label on the ballast housing and the color coding of the wires are the only means of determining which wires should be connected to the mains voltage and which wires should be connected to the lamp. Incorrect wiring of an electronic ballast, eg swapping the mains voltage connection and the lamp connection, can damage said electronic ballast when the mains voltage is applied. If mains voltage is applied to the ballast output, the DC bus is energized to power and the low voltage supply provides power to the control circuitry. The control circuit switches the MOSFETs, shorting the supply voltage via the diodes of the off MOSFETs, the on MOSFETs and the filter circuit. The short circuit continues until the MOSFET is damaged and opens, or the external circuit breaker opens. A damaged MOSFET renders the electronic ballast inoperable.

Electronic ballast assemblies are subjected to high temperatures and thermal stress when a lamp is ignited. During lamp start-up, the resonant circuit provides a high ignition voltage on the ballast output. The ignition voltage is a continuous ignition pulse that contains high-frequency voltage components. The resonant current flowing through the resonant capacitor and resonant inductor of the resonant igniter is high and energy is dissipated as heat in the resonant inductor. The higher and the longer the firing voltage is applied, the more heat builds up in the resonant inductor and raises the temperature of the inductor. When the core temperature of the inductor exceeds its rated limit, core breakdown occurs and renders the electronic ballast inoperable.

Another problem is that electronic ballasts use a sweep to start. In some electronic ballasts, as the ignition voltage is swept up, the inverter frequency is swept down in order to overcome the effect of cable capacitance and reach the resonant frequency used to generate the required peak voltage. This further degrades the inductor by allowing heat to build up during near resonant frequency. Additionally, slower ignition voltage sweeps reduce the likelihood of successful ignition, requiring repeated start attempts.

It is often desirable to have electronic ballast protection that overcomes the above disadvantages.

One aspect of the present invention provides a method of protecting an electronic ballast comprising providing an electronic ballast having an AC/DC converter, wherein the AC/DC converter has an electronic ballast input and a mains voltage connection connectable to a mains voltage, said electronic ballast also having an inverter operable to be connected to said AC/DC converter and having an electronic ballast output connectable to a lamp for controlling a control circuit for the inverter and a low voltage power supply for providing low voltage power to the control circuit; power is supplied to the low voltage power supply from the electronic ballast input when the supply voltage connection is wired to a supply voltage; and Power to the low voltage supply is disconnected when the electronic ballast output is wired to the supply voltage.

Another aspect of the present invention provides an electronic ballast protection system including an electronic ballast having an AC/DC converter having an electronic ballast input and a connected to a mains voltage connection of the mains voltage, the electronic ballast also having an inverter operable to be connected to the AC/DC converter and having an electronic ballast output connectable to a lamp for controlling the a control circuit for said inverter and a low voltage power supply for supplying low voltage power to said control circuit; means; and means for disconnecting power to said low voltage supply when said electronic ballast output is wired to said supply voltage.

Yet another aspect of the present invention provides an electronic ballast with ballast protection comprising an AC/DC converter receiving a supply voltage at a supply voltage connection and generating a DC bus voltage from said supply voltage, said AC/DC a DC converter having an electronic ballast input; an inverter receiving said DC bus voltage and producing output power at an electronic ballast output connectable to a lamp; a control circuit controlling said inverter; and a sensor connected, operable to connect to a location selected from the group consisting of said electronic ballast input and electronic ballast output, wherein said connection sensor provides a connection sensor signal to said control circuit, and when said connection The sensor signal is not the expected connection sensor signal, the expected connection sensor signal is missing due to incorrect wiring selected from the group consisting of the connection of the mains voltage to the output of the electronic ballast and the connection of the lamp to the mains voltage When , the control circuit 116 turns off the inverter.

Yet another aspect of the present invention provides an electronic ballast protection method comprising providing an electronic ballast having an electronic ballast input connectable to a mains voltage and an electronic ballast output connectable to a lamp, The electronic ballast input and the electronic ballast output are selected from the group consisting of the electronic ballast parameters and when the electronic ballast parameters are not the expected electronic ballast parameters due to the The electronic ballast is switched off when a selected miswiring in the group consisting of the connection of the voltage to the output of the electronic ballast and the connection of the lamp to the input of the electronic ballast results in a lack of a desired connection sensor signal.

Yet another aspect of the present invention provides an electronic ballast protection system comprising an electronic ballast having an electronic ballast input connectable to a mains voltage and an electronic ballast output connectable to a lamp for switching from means for monitoring an electronic ballast parameter at a location selected from the group consisting of said electronic ballast input and electronic ballast output, and for use when the electronic ballast parameter is not the desired electronic ballast parameter , shutting down the said Electronic ballast device.

Yet another aspect of the present invention provides an electronic ballast protection method, comprising providing an electronic ballast with an electronic ballast output, and generating an ignition voltage at the electronic ballast output during lamp start-up, the ignition The voltage includes a series of firing voltage pulses, wherein the series of firing voltage pulses are timed so as to limit the temperature of components in the electronic ballast.

A further aspect of the present invention provides an electronic ballast protection system comprising an electronic ballast having an electronic ballast output, and means for generating an ignition voltage at said electronic ballast output during lamp starting, The firing voltage comprises a series of firing voltage pulses, wherein the series of firing voltage pulses are timed to limit the temperature of components in the electronic ballast.

The above and other features and advantages of the present invention will become more apparent from the following detailed description when read in conjunction with the accompanying drawings. The detailed description and drawings are illustrative only and do not limit the invention, the scope of which is defined by the appended claims and their equivalents.

1 is a schematic diagram of an exemplary electronic ballast circuit;

2 & 3 are schematic diagrams of an electronic ballast circuit with ballast miswiring protection made in accordance with the present invention;

Figure 4 is a schematic diagram of an electronic ballast circuit with ballast ignition protection made in accordance with the present invention; and

Figure 5 is a trace of lamp ignition voltage for an electronic ballast with ballast ignition protection manufactured in accordance with the present invention.

2 & 3 are schematic diagrams of an electronic ballast circuit with ballast miswiring protection made in accordance with the present invention, wherein like elements share the same reference numerals as in FIG. 1 . Ballast Miswiring Protection Protects the electronic ballast when the line at the mains voltage connection 103 or the electronic ballast output 125 is miswired during installation.

Figure 2 is an exemplary embodiment of an electronic ballast circuit with passive ballast miswiring protection. Ballast miswiring protection is achieved by connecting a low voltage power supply 114 at the input of the electronic ballast such that the low voltage power supply 114 is isolated from the DC bus 112 . An electronic ballast input is defined as any location in the electronic ballast 200 that is operable to be connected to the supply voltage 102 prior to the DC bus 112 . In the illustrated embodiment, a low voltage power supply 114 is connected to the electronic ballast input at diode bridge-DC/DC converter connection 109 . In an alternative embodiment, the low voltage power supply 114 is connected to the supply voltage connection 103 or the EMI filter-diode bridge connection 107 .

When the electronic ballast 200 is properly wired, wherein the mains voltage connection 103 is wired to the mains voltage 102, power is supplied to the low voltage power supply 114 from the electronic ballast input. If the electronic ballast 200 is miswired during installation, such as by connecting the electronic ballast output 125 to the supply voltage 102, the low voltage power supply 114 will not receive power from the supply voltage 102, the control circuit 116 remains powered off, and inverter 120 does not switch. This prevents short-circuiting of the supply voltage 102 via the MOSFETs S1, S2, S3, S4 and the filter circuit 128 of the inverter 120, thereby preventing damage to the electronic ballast 200.

3 is an exemplary embodiment of an electronic ballast circuit with active ballast miswiring protection. Ballast miswiring protection is achieved by monitoring the electronic ballast connections and shutting down the electronic ballast when no expected indication is detected.

In one embodiment, an input sensor 302 as a connection sensor is connected to the electronic ballast input. An electronic ballast input is defined as any location in the electronic ballast 200 that is operable to be connected to the supply voltage 102 prior to the DC bus 112 . In the illustrated embodiment, the input sensor 302 is connected to the electronic ballast input at the mains voltage connection 103 . In alternative embodiments, the input sensor 302 is connected to the EMI filter-diode bridge connection 107 or the diode bridge-DC/DC converter connection 109 . The input sensor 302 may be a voltage sensor or a current sensor as desired. Input sensor 302 provides input sensor signal 304 to control circuit 116 as a connection sensor signal.

When power is applied to electronic ballast 300 , input sensor 302 monitors the electronic ballast input to monitor electronic ballast parameters, such as input voltage or input current, and provides input sensor signal 304 to control circuit 116 . The control circuit 116 determines whether the input sensor signal 304 is the desired connected sensor signal. The desired connection sensor signal is the presence of a signal indicating voltage or current on the input of the electronic ballast at start-up. When the electronic ballast 300 has been properly wired, the input sensor signal 304 is indicative of the supply voltage 102 providing power and the connected sensor signal is a signal present. Electronic ballast operation is allowed to continue. When the electronic ballast 300 has been miswired, such as wiring the mains voltage connection 103 to the lamp 124, the input sensor signal 304 indicates no power. Since the expected connection sensor signal is a signal present and the connection sensor signal indicates no signal is present, the control circuit 116 determines that a miswiring has occurred and turns off the inverter 120 to turn off the electronic ballast 300 . When the electronic ballast parameters are not desired electronic ballast parameters, the electronic ballast is shut down to prevent damage to the electronic ballast components.

In an alternate embodiment, an output sensor 306 is connected to the electronic ballast output 125 as a connection sensor. Output sensor 306 may be a voltage sensor or a current sensor, as desired. The output sensor 306 provides an output sensor signal 308 to the control circuit 116 as a connection sensor signal.

When power is applied to electronic ballast 300 , output sensor 306 monitors electronic ballast output 125 to monitor electronic ballast parameters, such as output voltage or output current, and provides output sensor signal 308 to control circuit 116 . The control circuit 116 determines whether the output sensor signal 308 is the desired connected sensor signal. The expected connection sensor signal is no signal present, indicating that there is no voltage or current on the electronic ballast output 125 at start-up. When the electronic ballast 300 has been properly wired, the output sensor signal 308 indicates that there is no power on the electronic ballast output 125 at startup and the connected sensor signal is no signal present. Electronic ballast operation is allowed to continue.

When the electronic ballast 300 has been miswired, such as wiring the electronic ballast output 125 to the supply voltage 102, the output sensor signal 308 is indicative of power. Since the expected connect sensor signal is no signal present and the connect sensor signal indicates a signal is present, the control circuit 116 determines that a miswiring has occurred and turns off the inverter 120 to turn off the electronic ballast 300 . When the electronic ballast parameters are not desired electronic ballast parameters, the electronic ballast is shut down to prevent damage to the electronic ballast components.

In another alternative embodiment, input sensor 302 is connected to the electronic ballast input as a first connection sensor and output sensor 306 is connected to electronic ballast output 125 as a second connection sensor. The input sensor 302 provides an input sensor signal 304 to the control circuit 116 as a first connection sensor signal and the output sensor 306 provides an output sensor signal 308 to the control circuit 116 as a second connection sensor signal. When the input sensor signal 304 or the output sensor signal 308 is not in its desired state at startup, the control circuit 116 turns off the inverter 120 to turn off the electronic ballast 300 . This further ensures proper wiring installation since the input sensor signal 304 and output sensor signal 308 must be in their desired state before the electronic ballast is allowed to operate.

FIG. 4 is a schematic diagram of an electronic ballast circuit with ballast ignition protection manufactured in accordance with the present invention, wherein like elements share the same reference numerals as in FIG. 1 . The firing voltage during start-up comprises a series of firing voltage pulses timed so as to limit the temperature of components in the electronic ballast and protect the electronic ballast.

In one embodiment, a temperature sensor 402 is provided for monitoring the temperature of a ballast component, such as the resonant inductor LR, and provides a component temperature signal 404 to the control circuit 116 . Component temperature may be monitored at the ballast component or on a circuit board in the vicinity of the ballast component. The control circuit 116 may adjust the operation of the inverter 120 to adjust the timing of the series of firing voltage pulses on the electronic ballast output 125 in response to the component temperature. Timing adjustments are further discussed below in conjunction with the description of FIG. 5 . The temperature sensor 402 is typically a semiconductor temperature sensor with a positive or negative temperature coefficient and is attached to or proximate the ballast assembly using a thermally conductive epoxy.

In an alternate embodiment, a voltage sensor 406 is provided to monitor the firing voltage at the electronic ballast output 125 during start-up and to generate a firing voltage signal 408 that is provided to the control circuit 116 . At initial startup after ballast installation, the control circuit 116 stores an initial output frequency corresponding to the desired firing voltage. The required ignition voltage is a high voltage that should occur at the fundamental frequency of the resonant circuit 126, or at a higher order harmonic frequency such as the third harmonic frequency, but actually differs from Fundamental or higher order harmonic frequencies. Determines the initial output frequency for the installed electronic ballast, thus resolving the uncertainty. Once the initial output frequency is known, the firing voltage (set by control circuit 116 controlling inverter 120 ) for subsequent starts is started at the initial output frequency plus a predetermined percentage, such as ten percent of the initial output frequency. The control circuit 116 sweeps down the output frequency from the initial output frequency plus a predetermined percentage to start the lamp.

In another alternative embodiment, a voltage sensor 406 is used to provide feedback to the control circuit 116 . The voltage sensor 406 monitors the firing voltage as the output frequency sweeps down from a starting output frequency, such as a predetermined percentage of the output frequency at which the desired output voltage is expected to occur. When the ignition voltage reaches the required ignition voltage, the drop of the output frequency is stopped. The output frequency is adjusted by the control circuit 116 in response to the firing voltage indicated by the firing voltage signal 408 to maintain the firing voltage at the desired firing voltage. From a limited scan using the voltage sensor 406 the ballast assembly is protected from overheating from longer scans and from repeated cycling from failed start attempts.

In yet another alternative embodiment, a voltage sensor 406 is used to provide a fire indication to the control circuit 116 . A lamp current sensor (not shown) monitors the lamp current of lamp 124 and provides an indication of the lamp current to control circuit 116 . The control circuit 116 detects lamp breakdown indicating successful ignition based on the ignition voltage and lamp current. The electronic ballast 400 continues to generate high frequency current at the electronic ballast output 125 during the first period after lamp breakdown, typically at a frequency above 20 kHz, in order to ensure successful ignition. The first period can be as long as 500 milliseconds and is typically 50 milliseconds. After the first cycle, the electronic ballast 400 generates a low frequency current at the electronic ballast output 125, typically at a frequency below 500 Hz. In one embodiment, electronic ballast 400 generates an ignition voltage at electronic ballast output 125 when the lamp voltage and lamp current indicate that the lamp has extinguished for a second period, such as after lamp breakdown 10 seconds. This restarts the ignition process when the previous start failed.

Figure 5 is a lamp ignition voltage trace for an electronic ballast with ballast ignition protection as in Figure 4 above. The lamp ignition voltage comprises a series of ignition voltage pulses timed so as to limit the temperature of components in the electronic ballast.

5 is an exemplary trace of firing voltage versus time showing a first series of firing voltage pulses and a second series of firing voltage pulses. The first series 500 includes a pulse portion 502 and a rest portion 504 . Pulse portion 502 further includes firing voltage pulses 506 alternating at voltage intervals 508 . Similarly, second series 510 includes a pulse portion 512 including voltage pulses 516 alternating at voltage intervals 518 and a rest portion 514 . The series of ignition voltage pulses continues during start-up until the lamp ignites. The series of ignition voltage pulses is typically a plurality of ignition voltage pulses.

Examples of ranges for the timing of the series of firing voltage pulses are 0.01 to 3.00 seconds, typically 0.90 seconds for the duration of each firing voltage pulse 506, and 0.01 to 30 seconds for each voltage interval 508, typically 6 seconds; 0.01 to 100 seconds for the duration of the pulse portion 502, typically 20 seconds; and 30 and 300 seconds for the duration of the rest portion 504, typically 300 seconds. The duration of each firing voltage pulse 506 and each voltage interval 508 is selected to prevent component temperatures, such as inductor core temperatures, from exceeding component temperature breakdown limits. The duration of the quiescent portion is chosen to allow cooling of the electronic ballast assembly. Those skilled in the art will appreciate that timing for a particular ballast depends on characteristics of the particular ballast design, such as electronic ballast components used, power output, enclosure ventilation, heat transfer characteristics, insulation, and the expected environment. Timing may remain constant from one series to the next or may vary as desired.

The firing voltage pulse parameters, ie the duration, voltage interval, pulse part and rest part of the firing voltage pulse, can be collected as a value set for timing the firing voltage pulse train in a specific case. For example, the timing of the series of firing voltage pulses may be a first set of values at the lower end of the firing voltage pulse parameter range when the component temperature is in a temperature band away from the component temperature breakdown limit. For example, when the component temperature is in a temperature band near the component temperature breakdown limit, the timing of the series of firing voltage pulses may be a second set of values at the upper end of the firing voltage pulse parameter range. When the component temperature is in a temperature band above the component temperature breakdown limit, the ignition voltage may be turned off to protect the ballast component.

The series of ignition voltage pulses are timed so as to limit the temperature of components in the electronic ballast. In one embodiment, the timing is calculated for a particular electronic ballast design and kept the same for the lifetime of the ballast. In an alternate embodiment, the timing is dynamically adjusted in response to electronic ballast measurements, such as component temperature, and may vary during a given start-up. In another alternative embodiment, the timing may be adjusted from one lamp start to another according to performance during a previous start or series of previous starts.

While the embodiments of the invention disclosed herein are presently considered to be preferred, various changes and modifications may be made without departing from the scope of the invention. The scope of the invention is indicated in the appended claims and all changes which come within the meaning and range of equivalents are embraced therein.

Claims (33)

1. An electronic ballast protection method, comprising: An electronic ballast is provided having an AC/DC converter 104, wherein the AC/DC converter 104 has an electronic ballast input and a mains voltage connection 103 connectable to a mains voltage 102, the The electronic ballast also has an inverter 120 operatively connected to said AC/DC converter 104 and having an electronic ballast output 125 connectable to a lamp 124 for controlling the control of said inverter 120 A circuit 116 and a low-voltage power supply 114 for providing low-voltage power to the control circuit 116; when the supply voltage connection 103 is wired to the supply voltage 102, power is supplied from the electronic ballast input to the low voltage supply 114; and When the electronic ballast output 125 is wired to the supply voltage 102, power to the low voltage supply 114 is disconnected. 2. The method of claim 1, wherein the AC/DC converter 104 receives the supply voltage 102 at a supply voltage connection 103; the AC/DC converter 104 comprises an EMI filter-diode operable to the bridge connection 107 is connected to the EMI filter 106 of the diode bridge 108 and the DC/DC converter 110 operable to be connected to said diode bridge 108 at the diode bridge-DC/DC converter connection 109; and from The electronic ballast input is selected from the group consisting of supply voltage connection 103, EMI filter-diode bridge connection 107 and diode bridge-DC/DC converter connection 109. 3. An electronic ballast protection system, comprising: An electronic ballast having an AC/DC converter 104, wherein the AC/DC converter 104 has an electronic ballast input and a mains voltage connection 103 connectable to a mains voltage 102, the electronic ballast The ballast also has an inverter 120 operatively connected to said AC/DC converter 104 and having an electronic ballast output 125 connectable to a lamp 124, a control circuit 116 for controlling said inverter 120 and a low-voltage power supply 114 for providing low-voltage power to the control circuit 116; means for supplying power from said electronic ballast input to said low voltage power supply 114 when said mains voltage connection 103 is wired to said mains voltage 102; and Means for disconnecting power to the low voltage power supply 114 when the electronic ballast output 125 is wired to the power supply voltage 102 . 4. An electronic ballast with ballast protection, comprising: AC/DC converter 104, which receives the mains voltage 102 at the mains voltage connection 103 and generates a DC bus voltage from said mains voltage 102, said AC/DC converter 104 having an electronic ballast input ; an inverter 120 that receives the DC bus voltage and produces output power at an electronic ballast output 125 connectable to a lamp 124; a control circuit 116 that controls the inverter 120; and a connection sensor operable to connect to a location selected from the group consisting of said electronic ballast input and electronic ballast output 125; Wherein the connection sensor provides a connection sensor signal to the control circuit 116, and when the connection sensor signal is not the desired connection sensor signal, due to the connection between the supply voltage 102 and the electronic ballast output 125 and the lamp 124 and The control circuit 116 turns off the inverter 120 when a selected miswiring of the group of connections of the supply voltage connection 103 results in a lack of the desired connection sensor signal. 5. The electronic ballast of claim 4, wherein the connection sensor is an input sensor 302 connected to the electronic ballast input, the connection sensor signal is an input sensor signal 304, and the desired The connected sensor signal is the signal present. 6. The electronic ballast of claim 5, wherein said input sensor 302 is selected from the group consisting of a voltage sensor and a current sensor. 7. The electronic ballast of claim 5, wherein said AC/DC converter 104 receives said supply voltage 102 at a supply voltage connection 103; said AC/DC converter 104 includes a EMI filter 106 connected to diode bridge 108 at diode bridge connection 107 and DC/DC converter 110 operable to connect to said diode bridge 108 at diode bridge-DC/DC converter connection 109; And said electronic ballast input is selected from the group consisting of said mains voltage connection 103 , EMI filter-diode bridge connection 107 and diode bridge-DC/DC converter connection 109 . 8. The electronic ballast of claim 4, wherein said connection sensor is an output sensor 306 connected to said electronic ballast output 125, said connection sensor signal is an output sensor signal 308, and the desired The connected sensor signal is no signal present. 9. The electronic ballast of claim 8, wherein said output sensor 306 is selected from the group consisting of a voltage sensor and a current sensor. 10. An electronic ballast protection method, comprising: Electronic ballasts are provided with an electronic ballast input connectable to the mains voltage and an electronic ballast output connectable to the lamp; monitoring an electronic ballast parameter at a location selected from the group consisting of said electronic ballast input and electronic ballast output; and When the electronic ballast parameters are not the expected electronic ballast parameters due to an error selected from the group consisting of the connection of the mains voltage to the electronic ballast output and the connection of said lamp to the electronic ballast input Turn off the electronic ballast when wiring leads to a lack of the desired connected sensor signal. 11. The method of claim 10, wherein the electronic ballast parameter is an electronic ballast input parameter monitored at the electronic ballast input, and the desired electronic ballast parameter is the parameter present . 12. The method of claim 11, wherein said electronic ballast input parameter is selected from the group consisting of voltage and current. 13. The method of claim 10, wherein the electronic ballast parameter is an electronic ballast output parameter monitored at the electronic ballast output, and the desired electronic ballast parameter is no parameter exist. 14. The method of claim 13, wherein said electronic ballast output parameter is selected from the group consisting of voltage and current. 15. An electronic ballast protection system comprising: an electronic ballast having an electronic ballast input connectable to the mains voltage 102 and an electronic ballast output 125 connectable to the lamp 124; means for monitoring an electronic ballast parameter at a location selected from the group consisting of said electronic ballast input and electronic ballast output 125; and Used when the electronic ballast parameters are not the desired electronic ballast parameters due to the selection from the group consisting of the connection of the mains voltage to the electronic ballast output and the connection of the lamp to the electronic ballast input A device that shuts down the electronic ballast when a faulty wiring leads to a lack of the desired connected sensor signal. 16. An electronic ballast protection method, comprising: providing an electronic ballast having an electronic ballast output 125; and generating an ignition voltage at said electronic ballast output 125 during lamp start-up, said ignition voltage comprising a series of ignition voltage pulses; Wherein the series of ignition voltage pulses are timed so as to limit the temperature of the components in the electronic ballast. 17. The method of claim 16, wherein the series of firing voltage pulses includes a pulse portion and a rest portion. 18. The method of claim 17, wherein the duration of the pulse portion is between 0.01 and 100 seconds and the duration of the rest portion is between 30 and 300 seconds. 19. The method of claim 17, wherein the pulse portion includes firing voltage pulses alternating at voltage intervals. 20. The method of claim 19, wherein the duration of each firing voltage pulse is between 0.01 and 3.00 seconds and the duration of each voltage interval is between 0.01 and 30 seconds. 21. The method of claim 16, further comprising monitoring component temperature and adjusting timing of the series of firing voltage pulses in response to said component temperature. 22. The method of claim 21 , wherein adjusting the timing of the series of firing voltage pulses in response to a component temperature comprises maintaining a firing voltage pulse parameter at a first set of values when the component temperature is in a first temperature band and when The firing voltage pulse parameter is maintained at a second set of values while the component temperature is in a second temperature band. 23. The method of claim 22, further comprising turning off the firing voltage when the component temperature is in a third temperature band. 24. The method of claim 21, wherein monitoring the component temperature comprises monitoring the component temperature at a location selected from a resonant inductor and a circuit board proximate to the resonant inductor. 25. The method of claim 16, further comprising: monitor the ignition voltage; storing an initial output frequency corresponding to a desired firing voltage during initial start-up; starting said firing voltage at the initial output frequency plus a predetermined percentage upon subsequent start; and The output frequency is swept down from the initial output frequency plus a predetermined percentage. 26. The method of claim 16, further comprising: monitor the ignition voltage; Sweep the output frequency down from the start output frequency; stop sweeping down the output frequency when the firing voltage reaches the desired firing voltage; and The output frequency is adjusted in response to the firing voltage to maintain the firing voltage at a desired firing voltage. 27. The method of claim 16, further comprising: Monitor ignition voltage and lamp current; detecting lamp breakdown based on said ignition voltage and lamp current; producing a high frequency current at the electronic ballast output 125 for the first period after lamp breakdown; and A low frequency current is generated at the electronic ballast output 125 after the first period. 28. The method of claim 27 including generating said ignition voltage at said electronic ballast output 125 when lamp voltage and lamp current indicate that the lamp is extinguished for a second period. 29. An electronic ballast protection system comprising: an electronic ballast having an electronic ballast output 125; and means for generating an ignition voltage at said electronic ballast output 125 during lamp starting, said ignition voltage comprising a series of ignition voltage pulses; Wherein the series of ignition voltage pulses are timed so as to limit the temperature of the components in the electronic ballast. 30. The system of claim 29, further comprising means for measuring a temperature of the component and means for adjusting the timing of the series of firing voltage pulses in response to the temperature of the component. 31. The system of claim 29, further comprising: means for monitoring the ignition voltage; means for storing the initial output frequency used to generate the required firing voltage during initial start-up; means for starting said ignition voltage at a subsequent start-up at an initial output frequency plus a predetermined percentage; and means for sweeping frequency down from said initial output frequency plus a predetermined percentage. 32. The system of claim 29, further comprising: Means for monitoring ignition voltage and lamp current; means for detecting lamp breakdown based on said ignition voltage and lamp current; means for producing a high frequency current at said electronic ballast output 125 for a first period after lamp breakdown; and means for producing a low frequency current at said electronic ballast output 125 after said first period. 33. The system of claim 32, further comprising means for generating said ignition voltage at said electronic ballast output 125 when lamp voltage and lamp current indicate that the lamp is extinguished during a second period.

Images