Re: [EVGRAY] Re: ballast cap vs run cap

Body

Great information from everyone,  yes the bleed resistor is usually in
the pic but until Ole mentioned they are only to start the ark I though
they were continuous duty.  Never looked at the lighting circuit Ole was
so thorough to include.

Warren said he procured a bunch of oil run caps rated at 1000v if memory
serves, have not seen any of these around yet.

Ole, what is the difference in the inside build between a non polar
electrolytic and an oil run or oil PFC cap?
I think the electrolytic fluid is different than the regular oil
insulation fluid but not sure.


On 5/5/2018 1:57 PM, [email protected] [EVGRAY] wrote:
>  
>
> Hi Mick,
>
> The ballast  of a HID (High Intensity Discharge) lamp would have to be
> an inductor. https://wiki2.org/en/High-intensity_discharge_lamp.
> <https://wiki2.org/en/High-intensity_discharge_lamp>
> The capacitor could be for a start discharge to get the arc ignited.
> This would be just a short pulse and thus wouldn't require a
> continuous high current through the capacitor.
>
> Here is a page with a schematic for an electronic ballast for HID
> lamps: https://www.repairfaq.org/sam/jshidbal.htm This circuit outputs
> DC current even though the Wikipedia article tells that DC isn't good
> for this kind of lamps. The C7 capacitor is the output capacitor that
> has the total voltage across it. This capacitor won't have big current
> through it as the current is limited by the series capacitance of the
> voltage multiplier and the output series resistor R3. A motor run
> capacitor will have the full run current of the help winding through
> it and thus must be able to handle that current through extended
> periods of time. Choose the capacitor for not heating above what the
> manufacturer recommends. The good capacitors are normally expensive as
> compared to the bad ones. Check the datasheets to see if fit for the
> purpose.
> SCHEMATIC GIF 8863 BYTES
> The schematic from the above link.
>
> Regards
> Ole
>
>
>
> ---In [email protected], <mkjekyll@...> wrote :
>
> Hector,
>
> If you can respond what is the difference between a HID lighting ballast
> cap and a run capacitor?
>
> The lighting caps are much less expensive, both are oil filled and both
> can handle a good amount of wattage.
>
> Is the internal build of say a run cap different offering higher Q or
> are they somewhat interchangeable?
>