Power Supply Recommendations

For my hobby build CNC router I'm leaning towards a 7i96E card and will need 5Vdc power. I'll also need 12 or 24V power for an e-stop circuit to pull in a couple mechanical relays. And also power all the travel limits.

What would you recommend as a PSU dual or multi-voltage out?

Depends on what can you find:
5V can be used from computer USB, requires cutting and wiring and VERY careful not to reverse the polarity
5V can be used from second hand USB mobile phone chargers, use original 5V ones for Samsung or Iphone, again polarity
16 - 20V can be used from second hand Laptop chargers, again original ones, very nice and very stable
5V and 12V can be used from an old computer power supply, same power supply provides both and some more
Or get new ones, a 5V and a 24V should do nicely
I personally never use a 5V power supply, i just cut a USB cable and wire to the controlling computer. That has also the benefit of being at the same potential, so grounding is taken care of.

Just get a 24 volt power supply. It does not have to be very big. (Mine is too big) If wired in correctly, 5 volt supply is not necessary on the 7i76e as it has its own on board 5 volt.
Also don't get a dual rail supply. I found you have to draw current on the 5 volt rail to get say 12 volt running and I have one here which has been useless. I added a power resistor on the 5 volt but it gets hot.

Then if running steppers a 48 volt supply would be perfect.

In case you use additionall bob do not forget to supply the bob's electronic with 5 volt too. (needed for the driver chips on the board).
Next trap is that those boards use optocoupler with separated supply, mostly based on 12 to 24 volts.
P. S.
The 7i76e does not need any of the "separation" games the bob provides for simple LPT connection. In my eyes it is not good to add a bob behind such a good card, but I ran into it myself
Mike

tommylight wrote: I personally never use a 5V power supply, i just cut a USB cable and wire to the controlling computer. That has also the benefit of being at the same potential, so grounding is taken care of.

Part of my reasoning going with an eathernet based card is the PC is not teathered to the router location.

tommylight wrote: Depends on what can you find:
5V can be used from computer USB, requires cutting and wiring and VERY careful not to reverse the polarity
5V can be used from second hand USB mobile phone chargers, use original 5V ones for Samsung or Iphone, again polarity
16 - 20V can be used from second hand Laptop chargers, again original ones, very nice and very stable
5V and 12V can be used from an old computer power supply, same power supply provides both and some more
Or get new ones, a 5V and a 24V should do nicely

I found in the 7i96e manual the host supply max current is 250mA no external load. The external loads are expansion cards correct? Does the 250mA also included the current soucing all the step and direction outputs to the drivers cards?

If you have teenagers these days you're probably swimming in cast off phone chargers, I have a ton of them. So the power off those 0.5A, 1.5A USB wall warts is clean enough to power the board?

5V wall warts are normally OK (check with a voltmeter first),
but beware of leakage from line voltage. I would not run
a non grounded switching supply like a cell phone charger
without grounding the 5V common to system/frame ground

On the 7i96e can you use the same 5v supply to power the board and the mechanical limit/travel switches? Is 5v on twisted pair shielded wire for limits adequate or should I use 12/24v?

You can use 5V for the 7I96 isolated inputs but you will have better noise immunity with 12V or 24V

meanwell got a duo 5V 24V
if you want to get better performance you may need 36V for tb6560 or tb6600
then next is 48V for the real good woodrouter
HAVE a look at the electronics we use for Hobby CNC at Education school