Originally Posted by
jtb00
Hello - I saw a 3-axis CNC machine yesterday that had 4 separate PSUs, all the same values. One for each driver, then another for the board. Each of these PSUs has 3 channels but only one is being used.
It seemed extremely wasteful to me, but the engineer who made the machine (they sell them) said there's two reasons for it:
1. It's easier for them to identify and service problems when a driver goes out. I have never heard of a single channel on a switching PSU going out without the others going out (correct me if I'm wrong, I'm no expert), so it would seem to me that point is of no benefit to them.
2. When there's a lot of stress/load as the machine works, spikes in amperage use can cause interference/missing steps, etc. As far as I knew, as long as your amperage had a little overhead for the maximum usage of the drivers and board, you'd be all set.
I did a little research and saw a couple people ratifying the second point there, but it wasn't specific enough for me to say whether or not it's a justified move to stock a machine with 4 PSUs when a single multi-channel, high amperage one would do the trick. I don't know enough about active/passive supplies, or electrical engineering in general to say this is all silly, so I come to you people. Is this actually a good idea? It seems like no money is being saved and there's no benefit to the company or the customer..