Re: Question about AC power distribution in CNC controller box

My home-brew controller box uses 4 Gecko 210s and a control board
that has 4 relays. I mounted 4 AC outlets on the back, switchable
via the relays. A single power cord is connected thru an AC line
filter. I think my line filter is rated at 15 amp. At any rate,
just make sure your power cord, AC line filter, power switch and
internal wiring can handle the maximum current of all your loads
operating at the same time. I would avoid using two power cords if
possible.

But if you decide to do so, I would not expect a ground loop problem
because the relay contacts are isolated from any other circuit (be
safe and check with an ohmmeter to insure each contact is in fact
isolated from common ground). I would tie the grounds from each
power cord to a single point on the chassis to avoid a small ground
current. Also make sure you wire your AC outlets such that hot &
neutral are not reversed to your loads.

Regards,
Ed Ferguson



--- In CAD_CAM_EDM_DRO@yahoogroups.com, "mrgamber" <mgamber@c...>
wrote:

>
> I am building a CNC controller.
>
> I plan on having 4 switched AC outlets on the back controlled by
> solid state relays.
>
> #1 is power to the servo drive power supply.
>
> #2 is spindle
>
> #3 is mist coolant
>
> #4 is flood coolant
>
> #3 and #4 are assumed to be very low AMP requirement.
>
> My question is, I want to put a 10A power entry module so I get it
> all in one plug. Is this a bad idea? Can I put 2 of these modules

and

> split the power between say #3 and #4 + controller electronics

power

> and the put #1 and #2 on a seperate power cord? This way I would

have

> 2 AC power cords entering one box. Is there a problem with ground
> loops if you do this?