Although many of our products have become industry standards and are available to all, often with slight modifications to suit, they nearly all began as custom solutions. We are reluctant to present a catalog of our nearly 1000 designs as we have found the best and most efficient approach is to deal with each requirement presented us on an individual basis. Based on the variety of parts and building blocks available to us we can customize a solution based, often, on existing, proven
and available components yielding a solution more closely suited to the application.
Design Examples
It is increasingly common for rotating anode x-ray tubes to be constructed with the motor stator at high voltage so as to provide closer coupling to the rotor. Usually these three phase motors are PWM controlled using a conventional three conductor x-ray cable to bring 440 volts to the motor but floating at 75 KV or higher. Typically the cable used is a standard cathode cable and the three wires which normally carry the cathode heater current rarely see more than 25 volts between them. These cables have performed well at 440 volts until recently.
DSI research has demonstrated that an unintended consequence of replacing older SCR drive systems with those using new, faster switches with much faster pulse risetimes can transform the cable into a transmission line with the effect of doubling the 440 volts at the stator end of the cable. This tends to occur on cables over about 50 feet long. Breakdown of the insulation between the conductors can occur over an extended period of time (months) due to corona damage.
DSI has designed a cable with superior insulation integrity and higher corona inception voltage to be used in cases where the anode stator drive is at high voltage. This cable is of the same size and flexibility as a standard cathode cable. It has been in service for three years without incident.
