Sisyphus

[ian]

Giving this another try...

Wiring 0.1.pdf

I have very little experience in electrical wiring but I have drafted the first wiring diagram and will appreciate any feedback to make sure I don't make any serious electrical mistakes!

Some key questions I have:

Is it good practice to use the terminal blocks to distribute the power
Should I connect the VFD as a separate feed from the mains or can I run it from a single main for the whole system
Should I connect the VFD via the relays (not sure the relay can support the power draw)

any help will be appreciated!

Components I will use:

5.5N Nema 24 Closed Loop Motors

2.2KW HY Spindle

Inductive sensors

230V, 60V, 10A Toroidal transformer

24V 15A Switching power supply

Masso G3

Masso Relay Module

[AndyUK]

Hi Ian

First thing that strikes me is you haven't fused things. That toroidal may also appreciate a D-Curve MCB.

The limit switches will probably want powering. I'd suggest some power indicators to notify you when things are live.

Just have a single earth bus rather than two.

I used DIN rail terminal blocks with bus bars. Seemed to work absolutely fine. Nice and tidy.

I connected my VFD through a single feed into the cabinet, but I used some noise suppression on the mains lines to reduce the noise output from the VFD. Just £3/unit from China. Commonly its suggested to take the VFD power feed from somewhere else in the room, but I can't tell you which is best. Some VFDs say in the manual not to turn them on and off via a relay, so I don't have mine on one.

If it helps, I've posted my circuit diagram on my build log, post 89, around page 9.

[JAZZCNC]

Hi Ian,

The schematic as a few issues I would address.
First off you don't have a safe E-stop system because you are only sending the E-stop signal to the controller so are relying on software to stop the machine. The NVR switch isn't doing anything so may as well just be a ON/OFF switch. The only way to take advantage of the NVR switch would be to run it through the E-stop contacts so when E-stop is hit the NVR does it job and drops power and won't reset untill E-stop is cleared. However this means running mains power through the E-stop and probably around the machine which isn't ideal.

So a better way is to drop the NVR switch for a normal ON/OFF contactor then create a latching Safety circuit using a relay and momentery button with 24V running through the E-stop circuit which is much safer.
This creates you an hard wired safety circuit which you can then control many things using the relay contacts or several relays in a circuit so when the E-stop occurs you can leave other things turned on which you don't want turned off when E-stop happens, like Motion controller and VFD etc.
You can also wire them to turn things on as well, like light towers or sirens warning you the E-stop happened or the Kettle so you can enjoy the Oh-Shite Hob knobs with a nice cuppa Yorkshire tea to console your self...

One of these contacts you would use to send the signal to the controller informing it the e-stop happened so it can stop the G-code. The other contacts you would use to Kill power to the toroidal transformer or a Contactor that feeds the toroidal PSU if it's high current.
Also one contact would send a signal to the VFD that an E-stop occured. Don't wire the VFD power through any relays, it should stay on when an E-stop occures but should be told to Stop and kill it's outputs.

Regards the spindle and water pump, the VFD as a relay built into it, use this for the water pump so the pump only runs when the spindle is turning.

The other thing is to only have ONE Ground point, STAR grounding, where every ground or shield wire runs too, if not you run the risk of creating Gnd loops.
The only exception is the VFD, with the VFD you take the spindle wire shield to the Gnd point on the VFD, the VFD Gnd is then taken from the STAR point.
Also only Gnd the shields at one end, usually in the control box.

You need fuses on the PSU's and VFD, I would also think about putting fuses on the drives, also the water pump and dust extraction.

The Terminal blocks are fine and a very easy way to create bus bars for pulling power from.