The Milltronics cnc mill needs a power modification. The old X axis DC motor used 120 volt single phase from a transformer in the mill. The new AC servo motor needs 208V 3 phase. Subsequently, I will need to supply the same power to the Y and Z axes when I replace those motors.
Are fuses necessary here since we’re staying inside the equipment box? I don’t think so, but there not a bad idea since we will be using lighter gauge wire then the 30 amp fuse would request. Not to mention, if a servo drive fails catastrophically. Better it blow up at 7 amps then at 30 amps. 😁 But these fuse block holders made by Phoenix Contact offer another benefit. You can bond them together. Meaning one wire can supply power to multiple fuses. It turns a fuse block into a distribution block.
And yet, I still ran jumper wires. But hay, not as many. 😁 The block can handle 10 amps. So how many can a block of fuse holders handle with one feed? I couldn’t find that answer, but I am guessing 10 amps. Though, considering the block could handle 8 gauge wires, plus two 14 gauge wires without an issue…. well, I have to wonder.
But where shall such a contraption be placed in such a confined cabinet! Well, removing the old X axis driver card opened up a nice location. It’s not perfect, but it’s a work in progress. I will be replacing a lot of the crap in this compartment because, well, it’s me. It’s what I do. 😎 So this location may change. Then again, it may not. I’m dodgy like that. 😂🤣
But why so many fuses? Well, It’s 3 phase, so we need to fuse each leg, which comes out to 3 blocks. These blocks separated by some grounding terminals. Each block contains 6 fuses. I need 4 fuses for axes, I need one single phase for fans, and one, ok fine. I got a bunch of these fuse blocks cheap on eBay and I fit as many as I could . I would have gone to 7 if I could. 😅
if you daisy chain, probably stays at 10 amps total. But if you home run to the power source, 10 amps each,
Yup, you can do that. But you would need to account for additional amps. It would work best if you knew that the drive would only be pushed to %50. If you had two drives pulling 10 amps, well, blown fuse. Which means I can’t do it since I’m part German. *screams in German* If it can’t work at %100, it can’t work at all!!!! LOL 🤣