Advice needed for controller box layout

**Clive S** · 07-01-2016

Have you thought about safety relay, estop, fuses etc

**Bustercnc** · 07-01-2016

Originally Posted by Clive S

Have you thought about safety relay, estop, fuses etc

I bought a EMI Panel Mount IEC Filter 10A from cnc4you to plug the power lead into thinking it was fused, just checked and its not.

I have a red panic button and proximity sensors for the estops.

Not sure what you mean by safety relay

**cncJim** · 07-01-2016

Hi Dave, looks good. I'm sure the extra space will soon get eaten up with wiring and other goodies like clive mentioned.

I would maybe swap the drives and the bob though and to try and keep the "clean" signal cables away from the "dirty" mains/drive power cables as much as possible?

I think most people would consider safety relays a step too far for smaller machines. They have features monitoring to detect if the contacts have welded shut but many don't worry about it. Really depend on your personal view of safety :)

I picked up a nice one for about £20 on ebay and it also has timed shutdown on one of the contacts which is nice. Can be quite large though and the ones I have seen are all din rail mounted.

Jim

**uli12us** · 07-01-2016

The parts, they produce most heat should be top. On the bottom side your box is open, you should close it with a dustfilter, similiar to the parts used in aquariums. And the heat must can flow out of the box, so you need another hole on the top or upper side of your box.

**Gotty101** · 07-01-2016

Like cncJim said the space will soon get eaten up. I was limited at the time by the cabinet size i could have so i had to work with that, although i managed to fit everything i wanted in. Dont forget space for the wire runs ect.

http://www.mycncuk.com/threads/8037-...k-Please/page7

There is a pic of my cab in there, your not putting the vfd in so that will help but it may give you an idea.

Trev

**JAZZCNC** · 07-01-2016

Really that case is little on the small side. You also need to think about heat and removing it with some fans.

Regards layout then first I wouldn't worry about trying to fit it all within in the confines of the plate because the reality is after it's wired you won't ever lift it out.

So I would put 2 drives up one side with one across top. The PSU like you have on it's side on the other side.
Then have the BOB Lower down because most of your wires connections will be coming in thru the bottom ie: Limits, E-stop, probes, etc
All Power and higher voltage wires or devices need to be kept far away from signal wires as possible and idealy run thru separate trunking crossing at a minimum. (See pic to get the idea of layout I mean)

You will need fuses for each drive and the main Psu. Regards Safety Relay then while you don't exactly need a Proper Safety relay with protected and monitored contacts you do need a Hardware driven safety system, which is what Clive S is refering too.

Relying just on Software E-stop is dangerous and shoudn't be used even on DIY router. Don't for one minute think this machine won't snap your arm like a carrot if get in the way, equaly neither will it think twice about ploughing it's cutter thru your hand just like it would a piece of Oak.!!

For this reason you need an E-stop safety system that uses a Relay to kill power to every thing that can hurt you. Then only after it's safe will it allow the system to Reset and Only with a Dedicated Momentery Reset button not just by releasing the E-stop button.

The extra cost is minimal so it's stupid to not do it.

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**Bustercnc** · 08-01-2016

Originally Posted by JAZZCNC

Relying just on Software E-stop is dangerous and shoudn't be used even on DIY router. Don't for one minute think this machine won't snap your arm like a carrot if get in the way, equaly neither will it think twice about ploughing it's cutter thru your hand just like it would a piece of Oak.!!

Jazzcnc comment stuck with me and I felt kinda insulted by it.
Afterwards I spent many hours reading forums and manufacturer specs in fear of duplicating many of the stupid/repeat questions already asked, it dawned on me, what kind of person is going to stick their hand infront of a drill bit when something goes wrong? instink dictates that you would pull the plug in the event of the estop failing.

No matter how many safety features are employed, the above will still happen unless a trip switch is fitted on a enclosure door, NOT mentioned in all that I have read so far

**Bustercnc** · 07-01-2016

Wow Trev,

That is one busy looking controller box. I noticed 3 safety relays in there. Your case looks to be the same as mine only bigger.

I do have a vfd for my mill but I had (its in storage at the moment) this mounted to the wall behind the mill.

**JAZZCNC** · 07-01-2016

Originally Posted by Bustercnc

Wow Rev,

That is one busy looking controller box. I noticed 3 safety relays in there. Your case looks to be the same as mine only bigger.

I do have a vfd for my mill but I had (its in storage at the moment) this mounted to the wall behind the mill.

Nope only 1 safety relay and one Icecube relay. Yes it's same but bigger and deeper.

**Bustercnc** · 07-01-2016

Originally Posted by uli12us

The parts, they produce most heat should be top. On the bottom side your box is open, you should close it with a dustfilter, similiar to the parts used in aquariums. And the heat must can flow out of the box, so you need another hole on the top or upper side of your box.

Hi Uli12us,
The case comes with a blanking plate for the hole in the bottom, I was going to fit the stepper connectors and power socket into that.
Agreed, some more work does need to be done to provide ventilation