Drsstc -enclosing/shielding bridge and driver together, proximity to primary?
starshippilot, Fri Jun 20 2014, 07:56AMI'm beginning to rethink this enclosure for a big DR
Should I be enclosing the driver only?
What would be the consequences for high proximity to primary?
Eddy current losses?
If it is ok, this should be grounded mains, right?
here's a pic
Re: Drsstc -enclosing/shielding bridge and driver together, proximity to primary?
Mads Barnkob, Fri Jun 20 2014, 09:20PM
Just do not make the enclosure a closed loop so it appears as a one turn load to the primary.
Dr. Spark have had problems with wire fence getting heated from induction, but I think he mentioned it only became a problem at power above 15kVA.
Ground it to your one and only ground where you connect everything, at one single point.
Are you planning to oil cool the primary in that blue circular swimming pool its placed in?
Mads Barnkob, Fri Jun 20 2014, 09:20PM
Just do not make the enclosure a closed loop so it appears as a one turn load to the primary.
Dr. Spark have had problems with wire fence getting heated from induction, but I think he mentioned it only became a problem at power above 15kVA.
Ground it to your one and only ground where you connect everything, at one single point.
Are you planning to oil cool the primary in that blue circular swimming pool its placed in?
Re: Drsstc -enclosing/shielding bridge and driver together, proximity to primary?
starshippilot, Sat Jun 21 2014, 02:13AM
Thanks mads, There is aluminum along the bottom
electrically connected and I was going to use
aluminum screen across the top of the aluminum
diamond plating Forming a box enclosure
Yes I was planning to immerse the primary in this tub
To cool it, and this would also insulate from flash over
Think it'll work?
starshippilot, Sat Jun 21 2014, 02:13AM
Thanks mads, There is aluminum along the bottom
electrically connected and I was going to use
aluminum screen across the top of the aluminum
diamond plating Forming a box enclosure
Yes I was planning to immerse the primary in this tub
To cool it, and this would also insulate from flash over
Think it'll work?
Re: Drsstc -enclosing/shielding bridge and driver together, proximity to primary?
starshippilot, Sat Jun 21 2014, 05:14AM
Is shielding the driver alone just as effective?
More on the primary const:
I cut a 55gal poly E. drum and a
smaller drum.
Then used a couple tubes worth of silicone to make a gasket
to mash In between the tubs. The silicone is compressed
via threaded pvc fittings which alow the sec rf ground down
through it.
The inner tube will allow the secondary to sit recessed
in the primary for higher coupling while reducing oil quantity.
starshippilot, Sat Jun 21 2014, 05:14AM
Is shielding the driver alone just as effective?
More on the primary const:
I cut a 55gal poly E. drum and a
smaller drum.
Then used a couple tubes worth of silicone to make a gasket
to mash In between the tubs. The silicone is compressed
via threaded pvc fittings which alow the sec rf ground down
through it.
The inner tube will allow the secondary to sit recessed
in the primary for higher coupling while reducing oil quantity.
Re: Drsstc -enclosing/shielding bridge and driver together, proximity to primary?
Goodchild, Thu Jun 26 2014, 10:51PM
With a good PCB design shielding the driver is usually not even necessary, I have seen it work countless times without it. A lot of new comers makes the mistake of thinking that their driver needs more shielding when it's not working properly, when in actuality it's usually some other issue.
That being said a metal mains grounded box around your driver is not a bad idea. It's not going to hurt anything and will help you sleep better at night.
The rest of the electronics (bridge, MMC, primary) could care less if you put them in a metal box or not. I would however stay away from any kind of large metal sheeting around the base, it's generally not a good because of eddy currents being induced. This heats up your base and makes it hard to tune.
Good luck!
Goodchild, Thu Jun 26 2014, 10:51PM
With a good PCB design shielding the driver is usually not even necessary, I have seen it work countless times without it. A lot of new comers makes the mistake of thinking that their driver needs more shielding when it's not working properly, when in actuality it's usually some other issue.
That being said a metal mains grounded box around your driver is not a bad idea. It's not going to hurt anything and will help you sleep better at night.
The rest of the electronics (bridge, MMC, primary) could care less if you put them in a metal box or not. I would however stay away from any kind of large metal sheeting around the base, it's generally not a good because of eddy currents being induced. This heats up your base and makes it hard to tune.
Good luck!
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