View Full Version : Dead 6040 controller box

13-08-2017, 10:55 AM
Hi Everyone,

Bit of a problem here and i'm after a bit of advice from anyone who has heard of this problem or can put a finger on the fault.

It's a generic ebay 6040 chinese cnc that has been happily cutting away for the last 18 months, i only work with wood so i never needed anything heavy duty and as i say it's been working fine until i made a mistake with a clamp placement, the tightening collar for the collet on the spindle came into contact with the clamp and as the clamp was going nowhere it slowed the spindle to a complete stop before i could hit the emergency stop button and i lost all power to the box.

Thinking the power supply unit had blown i ordered a new one, this duly came and i replaced it carefully making sure i swapped all the leads to the correct places and it's still as dead as a dodo, the power switch on the box itself is my next guess as it's rated at 15a and could have blown if there was a power surge with the spindle being stalled.

That's the real problem though i'm only guessing, replacing everything one by one is not really an option due to the expense, and some of the things like the internal nowforever vfd seem hard if not impossible to source in the UK.

My electrical experience is nil so has anyone any ideas? i thought that if it was the vfd or spindle then the box would still power on, unless it's all connected creating the circuit so if one component is dead it renders the rest useless.

Any input appreciated fellas and cheers for taking the time to read :calm:

john swift
14-08-2017, 09:43 PM
with all the variations in what components are used in the "6040" machines
a few photos of the spinde motor and the inside of the control box will help

once the components used is known , it will be possible to work out how to test the various parts


do you have a multimeter ?

14-08-2017, 09:59 PM
Cheers John and a good point, i'll upload some pics after i get in from work tomorrow.

I have a very basic multimeter to match my very basic knowledge of using one :smile:

14-08-2017, 10:39 PM
photos would certainly be helpful.

I assume you've done the obvious like check the fuse in the main plug? Since you hit the physical emergency stop button I assume you've made sure you twisted it and it popped back out fully?

A multimeter is really required for any trouble shooting, I assume you have one?

15-08-2017, 08:48 PM
Yep Zeef i've tried the obvious first, i would have been chuffed if it was the fuse but it's never that simple is it :biggrin: and yes i popped the e-stop back out again, i do have a really basic multi-meter but my sum experience with it is checking the voltage of a battery.

Excuse the delay in replies fellas, i did reply to you both fairly quickly but it seems they have to be cleared by a moderator first.

Anyway here's the pics


and the spindle, it's 2.2kw water cooled


hope the image quality is good enough.


15-08-2017, 08:51 PM
with all the variations in what components are used in the "6040" machines
a few photos of the spinde motor and the inside of the control box will help

once the components used is known , it will be possible to work out how to test the various parts


do you have a multimeter ?

Thanks John, i did reply to you but my reply never appeared, weird one that, pics as requested :tennis:

john swift
15-08-2017, 11:15 PM
I can not see very much detail but I guess the control box and VFD will look like this

does any thing light up ?

provided the mains fuse in the plug and the 20mm fuse in the mains inlet is OK
I would expect the main on off switch to light up

whats not clear from the photo is if the E-stop switch breaks the mains supply the switch mode power supply and your VFD drive
or if its just signals an E-stop to Mach3 (or what ever control software your using


watch out when ever you unplug the spindle from the control box to test it without the spindle motor being connected

the Chinese very often use chassis mounting plugs as mains out lets !!!!

16-08-2017, 06:39 AM
Nothing lights up at all John, completely dead, that's why i'm hoping it's the main power switch on the box that has gone, because if it isn't then surely i would get something.

Those pics look accurate you posted, and the e-stop is wired into the power switch on the front of the box, i have a switch coming tomorrow so i can test that theory.

16-08-2017, 10:46 AM
So when you flip the power switch, does your PSU produce whatever voltage you would expect when measured with the multimeter? (Most of these machines are 40v I believe these days).

If your new PSU doesn't produce any voltage, then it would be fairly safe to assume your problems lie in the e-stop area.

Oh did you check if the kettle cord input plug on the chassis has a separate fuse? Some do.

john swift
16-08-2017, 11:07 AM
most machines have a fused IEC inlet like this

have you checked both fuses - in the plug & mains inlet ?

with the power off you should be able to prove
you have continuity between the L, N & E terminals on the back of the inlet and the 3 pin plug

as the E-stop switch is a single pole mains switch
it should break the live supply from the IEC inlet -
double check the switch is working and it does not switch the neutral as the Chinese have a habit of doing

resistance checks on the double pole on off switch should prove if its working , or not


a possible wiring diagram

note - the E-stop is shown as being after the main ON/OFF switch
it could be before

16-08-2017, 09:37 PM
You nailed it fellas it was the fuse in the mains inlet, i wouldn't have known that was there with a gun to my head.

Appreciate all the input and advice lads, thanks very much :beer:

john swift
16-08-2017, 09:41 PM
great result

16-08-2017, 10:07 PM
Always satisfying to see someone fix they're problem ;) Good tip on the fuse I didn't know that either but mentally noted.