Hi
Once we find power supplies specifically designed for capacitor charging, we come up with negative high voltage supplies. Why is it?
Hello Rai Naveed Arshad ,
Can you give an example of a company or companies that provides mostly negative polarity power supplies for capacitor charging?
Regards,
Thomas Cuff
Hello! Rai Naveed Arshad,
During discharging, the direction of the current is opposite to the original current direction(source current). so the current is negative. likewise, the discharging voltage direction is also opposite to the source voltage direction.
since the -ve charge on the -Q charged plate has a greater effect on the +Q charged plate, resulting in more electrons being repelled off of the +Q charged plate, and thus increasing the overall charge.During discharging, the direction of the current is opposite to the original current direction(source current). so the current is negative. likewise the discharging voltage direction is also opposite to the source voltage direction.
Hello Shahnawaz Alam and Indirajith Kanagaraj ,
I am confused. Both of you speak of the capacitor discharge current going in the opposite direction from the charging current, but the capacitor is being discharged by its load, e.g., a laser flash lamp, not by the capacitor charging power supply; the load is in a separate loop from the charging loop. The discharge current does not go back through the capacitor charging power supply, which why it is called a capacitor charging power supply, and not a capacitor discharging power supply. In fact, once the capacitor is fully charged, it may be disconnected from the power supply by either a mechanical or electronic switch or simply a diode connected between the capacitor and the power supply.
In addition, I do not understand what you both mean when you say that the capacitor discharge voltage is in the opposite direction from the power supply polarity. The positive terminal of the capacitor, when it is being charged, is still the positive terminal when it is connected to the load. The only way the voltage difference across the capacitor reverses is if the load is an inductor and the resistance of the load is small enough that the resulting LRC circuit is underdamped.
Regards,
Thomas Cuff
Hello Rai Naveed Arshad ,
I have uploaded both the Spellman 2022 Product Catalog (Spellman.pdf) and the 2022 High Voltage Reference Manual. Most of the power supplies, in the Product Catalog, say you can specify the polarity at the time you place your order. The Reference Manual, on p. 14, echoes the Product Catalog.
The capacitor charging power supplies models CCM1KW (pp. 260-262) and CCM (pp. 263-264) are either positive or negative at the time of order, or positive, respectively.
Regards,
Thomas Cuff