Safest way to split AC line and residual power

Hi all,

For my current project I need to power two devices (CNC spindle PSU, and Motor PSU) in parallel from a single AC line. What is the safest way to split the live line into 2 ?
There seems to be quite a few options, the obvious is to simply strip the end of the cable then solder two wires to it then cover with heatshrink. Another option would be to use a screw screw terminal. One end would have a single live wire the other end would be two blocks shorted together to produce a parallel connection. Another option is the chassis on/off switch is SPDT I could short the output end to produce a parallel connection at this point too.
Does anyone have any thoughts on which is the safest ? AC power at that voltage is not something I want to take chances with.

My other question is regarding the E-Stop switch. Currently my wiring design is the following-

AC Mains -> IEC socked-> E-STOP Switch -> Chassis On/Off Switch-> load (PSU)


I've noticed when I turn off the AC line at the moment the Motor PSU's LED stays on for a few seconds afterwards, must be the caps discharging.
I know its only a few seconds but is the implication here that power will continue to be supplied for a moment after the AC line is cut, if so should there be switch coming out of the PSU to cut power at that point ?

All help appreciated.

Edited 1 time(s). Last edit at 06/02/2015 05:34AM by eci22.

They should be on independent fused circuits.

For an E-stop circuit, power removal has to be immediate, no gradual discharge. So, the E-stops have to act on the output of the PSU's. Ideally, the best place for the E-stops would be to disconnect the power feeds between the motors/steppers and their drivers.

One feed, two PSU's. One cable coming in. Split into two and fed to two separate fuse blocks with line and neutral fused. One fuse block pair is for the spindle PSU and the other fuse block pair feeds the motor PSU.

Thank you for the responses.

Something I forgot to mention is the IEC socket is already fused, therefore does fusing the individual units become redundant ?

About putting the E-STOP between the motors and their drivers, the issue I see here is what if there's a problem with the PSU's or with the micro controller (Arduino), also in that position the spindle would stay powered.

Thanks again for your help

Quote
eci22
About putting the E-STOP between the motors and their drivers, the issue I see here is what if there's a problem with the PSU's or with the micro controller (Arduino), also in that position the spindle would stay powered.

Don't put a switch between the motors and the drivers, because activating such a switch is likely to damage the drivers. The simplest way of stopping the stepper motors instantly is to reset the microcontroller on the electronics board.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].