power distribution blocks

[ceencee]

Good day, im laying out my electrical schematics now from the very beginning. I have some questions. Ive been researching power distribution blocks....there is more of them than i care to look at. Im inputting 35-40 amp 3 phase supply line, after the connection terminal and going through the cabinet lock switch i need a power distribution block. I cant find one with 1 input and 5 or more outputs, or i am finding them but i dont realize what they are saying in the specs. Is there one company that makes simple and effective units without bells and whistles?
If i want to pull a 120 V leg off the three phase power to supply the 120 V transformer is it as simple as taking L1 and a neutral ground. I did it on a power feed on a big bandsaw but do you think i can remember lol.
Another question i have concerns overloads. I will be putting in motor starters for a couple of the non variable speed motors.Some of these starters can come with adjustable overloads built into them. If i use them do i still need to use a dedicated overload before the starter? Overloads only protect for excessive current,so is it recommended to put a fuse in each circuit for shorts or is this not necessary?

Thanks
Wade

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[Al_The_Man]

Because usually after the disconnect you need fusing for the distributed power, What I generally do is daisy chain the three phases using appropriate sized cable across DIN rail mount fuse blocks, the fuse blocks I use have two conductor entry to facilitate this, if you lay it out so that the fusing size gets progressively smaller, the corresponding cable size can be reduced as you progress across the panel.
Contactors that have O/L fitted still require fuses before them, but just the one O/L.
Do not use a ground as a feed conductor, if only 3ph is entering the panel, then wire a transformer across 2 ph with appropriate primary, with 120v secondary.
It is customary to ground one of the 120v secondary leads to set up a local grounded neutral, I have previous posts here on how to accomplish this.
If getting into machine control wiring, it is worth springing for a copy of ANSI/NFPA78, it runs around $40.00.
This also explains the local neutral I mention, as well as Electrical Code.
Al.

[Al_The_Man]

That should read NFPA79.
NFPA 79: Electrical Standard for Industrial Machinery
NFPA 79: Electrical Standard for Industrial Machinery
Al.

[ceencee]

Thanks AL, I bought the book in pdf form and printed it off. Will be tonights reading. Looks like it will answer alot of my questions.

Thanks
Wade