Wiring, Check Please
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Hi all,
I'm building a large delta similar to dc42s large kossel https://miscsolutions.wordpress.com/dc42s-large-kossel-build/
As I'm using a 230V AC heater for the bed I want to make sure I've got the wiring right based on David's photos in the above post.
So if someone wouldn't mind taking a quick look at the diagram below that would be great. Have I missed anything?
Also I'm a bit unsure why one of the -V outputs on the power supply needs to be connected to GND?
Thanks
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Yes, that's the correct wiring.
The reason for grounding V- is so that if the PSU develops an insulation fault in its transformer, the low voltage wiring doesn't become live.
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Ah excellent, thanks for confirming.
I'll post some photos here once I'm a bit further along with the build.
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While we're here speaking about the ground bridge…
Would the same effect be achieved by connecting the PSU in the manner shown in these instructions? https://ohai.lulzbot.com/project/277a1005-46c1-4b99-bc60-f39965c395f0/a16b1f2d-5c1f-47fe-a83d-9d68cca5d62c/
Particularly, the PSU is screwed into a metal frame which is itself connected to earth ground. Does this effectively protect against transformer insulation faults?
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Probably not. The PSUs I have here do not have a connection between the V- output and the metal frame.
Leaving out the ground connection avoids the USB ground loop issue that I describe at https://duet3d.com/wiki/Important_note_on_using_a_USB_connection; but IMO, safety is the overriding concern.
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Probably not. The PSUs I have here do not have a connection between the V- output and the metal frame.
Leaving out the ground connection avoids the USB ground loop issue that I describe at https://duet3d.com/wiki/Important_note_on_using_a_USB_connection; but IMO, safety is the overriding concern.
Thank you for the answer! Sorry, I just saw it now.
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BTW there is a video on Maker's Muse about why the negative output from the PSU should be linked to ground.