I'm currently building a 230V Distribution box with a DC blocker (Bryston principle) and 2 stage AC Filtering in a Audio case.
In the frontpanel there will be a digital meter for displaying AC, dc, freq. and Ampere, and also a store function to display the variation on the AC line in time (max 14 days).
Just did the cutting holes and deepened on both sides
Assembly
In the frontpanel there will be a digital meter for displaying AC, dc, freq. and Ampere, and also a store function to display the variation on the AC line in time (max 14 days).
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
Just did the cutting holes and deepened on both sides
An externally hosted image should be here but it was not working when we last tested it.
Assembly
An externally hosted image should be here but it was not working when we last tested it.
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All I can say about this idea of DC being present on a household mains supply is that the supply must be sub standard to allow a half wave drain raise the zero point on the AC mains. Even dimmer switches for lighting use triacs so keeping an equal load. I am not aware of any machine that uses only half of the mains cycle. I await to be enlightened with some evidence. Until then, I will add this to the snake-oil theories and ludicrous ideas.
Yes, schematic is just L/N, i know how to assemble electronic parts.
Case will also be on earth protection.
Just forgot to draw PE in the schematic part.
Just for testing (component placements):
Left in the backpanel there will be a switch, automatic fuse and the DC Blocker.
After that a 2 phase filter unit which goes to the power supply (for powering the digital meter) and the outlets.
Empty space on the right will be used for cables.
An externally hosted image should be here but it was not working when we last tested it.
Left in the backpanel there will be a switch, automatic fuse and the DC Blocker.
After that a 2 phase filter unit which goes to the power supply (for powering the digital meter) and the outlets.
Empty space on the right will be used for cables.
Placement could be changed. The filter could be on the left side near the wall where the switch is positioned (short cable) and the dc blocker right next to the filter.
If there are cables running to the switch before the filter these too must be well screened. The switch will also need to be well screened.
It might be better to use dual filters. The normal screened can, IEC socket plus integrated filter. Then screened cable to the switch and screened cable back the the big canned filter.
It might be better to use dual filters. The normal screened can, IEC socket plus integrated filter. Then screened cable to the switch and screened cable back the the big canned filter.
Ok, thanks !
But i don't use a seperate inlet because the power cable will be mounted directly.
Would it be fair to say that there is no performance level required of this box except to ensure that it has certain 'filter' parts inside it, and a nice front panel with a modern AC meter on it?
Are the filters there to save the mains supply from gross high crest-ratio current spikes drawn by a large toroidal traffo, and diode recovery spikes due to gross capacitive filtering that you have in your audio gear?
Are the filters there to save the mains supply from gross high crest-ratio current spikes drawn by a large toroidal traffo, and diode recovery spikes due to gross capacitive filtering that you have in your audio gear?
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Correct. Esthetic!
The filter part is just a 2 stage filter with a very high differential and common-mode attenuation.
It works from about 40kHz - and up, so no attenuation in the audio area.
The other part is a dc blocker.
you must screen that cable, otherwise it will negate your efforts to attenuate RF coming in via the cable.
The filter inside the chassis is too late, the RF is already inside.
Thanks for your suggestion.
Question: what about the cable connected to the switch, this will be (as most cables are) a non shielded cable.
Does it realy make that much difference if i use a 5 - 8cm shielded cable from the switch to the filter?
your switch and the filter should be outside the RF screening box.
An integrated IEC socket with switch and fuse and filter effectively puts that whole lot outside the box by enclosing them inside their own can and that can becomes part of the Faraday Cage wall.
Even though this fiter is not as good as a bigger internal filter, it may give more effective RF attenuation by being outside rather than bringing the interference inside and then attenuating.
You then have the option of adding a second filter.
This second filter can be inside the box but fastened to the Faraday Cage wall (floor).
The cable to the filter still needs to be screened and that screen must be bonded to the box at both ends.
An integrated IEC socket with switch and fuse and filter effectively puts that whole lot outside the box by enclosing them inside their own can and that can becomes part of the Faraday Cage wall.
Even though this fiter is not as good as a bigger internal filter, it may give more effective RF attenuation by being outside rather than bringing the interference inside and then attenuating.
You then have the option of adding a second filter.
This second filter can be inside the box but fastened to the Faraday Cage wall (floor).
The cable to the filter still needs to be screened and that screen must be bonded to the box at both ends.
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