The Sciencetech 500-200 and 550-200 Power Supplies require this mandatory 500-IG external ignitor for starting arc lamps. This ignitor is connected in series to the Power Supply and automatically generates a 20kV spike to ignite the arc lamp. The ignitor can detect the presence of an arc lamp and will automatically try to ignite it up to 5 times once the power supply has been turned on.
 
This is the igniter recommended for the 200-100 & 201-100 Series Arc Lamp Housings.