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Instant ignitor setup
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As Metal halide lamps require much higher ignition voltages when hot, most standard lamps can not be i stantly reignited after a power cut. This can brcome problematical when these lamps are used in sensual locations such as prisons or military installations. It can also be inconvenient when these lamps are used in sport stadiums or other public places when after a brief power drop during the transfer from grid to emergency power the light goes out and cannot start again for the next ten to fifteen minutes.
In order to reignite a lamp with hot discharge tube, ignition spikes between 15-60kV are necessary. The lamp and entire luminair needs to be constructed in a manner to withstand these pulses. This is the reason why many hot restrique lamp are double ended like Osrams entire HQI-TS series or Philips series of rare earth stadium lamps of the MHN series.
Generally the insulation of the lamp holders and wires bust be increased. In the same time the capacitance of these must be kept ad low as possible to ensure reliable ignition.
Special ignitors are made for this application that are symmetrical, putting a high pulse that is phase shifted by 180 degrees on each lamp connection effectively doubeling ist voltage.
I build this set up as it would be impossible to integrate such an ignitor in my testbench.
The ignitor is a symetrical BAG Turgi ignitor for up to 13A and for operation on both 230V and 400V. The ignition voltages can be set via a wire bridge internally to 25, 30 or 40kV. Im build this set up in a way so that i can change the top plate. Currently an plate is mounted that can work with Osram HQI-TS 2000W lamps as well as soviet hot restfique MH lamps. In the background a plate for FC2 based lamps, Osram powerstar HQI-TS 250W, 400W and 1000W can be seen.
it can be changed and the lampholders are connected by M8 screws on the porcelain bus bar insulators.
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