[RaptorZ]

Long time lurker, first time poster.
I've finally bought my first CNC mill after a few failed attempts at making a wooden one in the past.
I went for a Chinese 6040 mill, and also ordered a G540. I managed to get the PRT-E1500W VFD working and replaced the power supply with a 48V one for the gecko.

However my issue is with the motors that came with the machine, i cannot get them to turn reliably. them mostly just shake. Unfortunately as they have no stickers on them I am having difficulty identifying what they are.
I believe the gecko is working correctly, as it moves some old steppers quite happily.

kind regards
Ben
Attachment 360562

[coherent]

Look through any documentation you received or can find online for the 6040 you bought and see if somewhere there is a notation of the stepper specifications. You most likely noted that the G540 requires current limiting resistors on the connectors that match the motors. Without insuring they are correct you may damage something. I have no idea what your original power supply voltage was, but it's likely that the power supply and and steppers that came with the 6040 are a lower voltage/amp setup. You can measure/determine the amperage and inductance of stepper motors without having the spec sheet. Do some research online and and you'll find more info and instructions on how to do so. Maybe someone with the same machine will chime in that has the same motors and knows the specifics.
Good luck.

[RaptorZ]

Thank you very much for your response, I will have a look to see if i can identify the inductance of the windings.
The current information I can find on the sellers listing are: Stepping motor:57 two-phase 3A 150N.cm
They where running on a 24v PowerSupply
I was performing the testing of the motors with a 2k resistor to limit the current to minimise the chance of damage.

Many thanks

[john-100]

with a multimeter
check you have correctly the identified the motor windings

was it originally a 3 or 4axis 6040 router ?

what was the original stepper drivers ? - if you can find the data sheet you will be able to find out what the motor current was

what was the spec for the original power supply ?

Assuming al the motors take the same current ,
I would divide power supply current by the number of axis and then multiply the result by 1.4

this will be close to current setting needed for your G540

for example
if you had a 6A power supply and 3 axis ( set for the same motor current)
then the 3 drivers will each take 2A from the power supply
multiplying by 1.4 gives you a driver motor current of 2.8A !

the motor current is larger because the power supply only has to replace the resistive and eddy current losses
the extra current comes from the recovered energy circulating in the motor windings


John

[RaptorZ]

ok, so i have checked the continuity from the drives to the DB9 connector, now i feel like an idiot, somehow I connected the coil across A and B, and the other across A' and B'
the machine was a 4 Axis device, this one on eBay 4 Axis CNC 6040 desktop Engraving Router Machine Precision Ball Screw 1.5KW int | eBay
Attachment 360594

unfortunately, the original drivers where unbranded, and i have yet to locate the datasheet for driving them.the main marking is TX14207, using a "toshiba" TB6560AHQ
Attachment 360596

the power supply was a 24v 6 Amp device, though it had a smaller motor on the A and Z axis, and a larger ones on X and Y.

thank you so much for your assistance, im going to go back and fix my mistake, and set the currents from your advice.

Ben

[john-100]

Hi Ben

That's good you have found why the motors don't turn as expected

looking at the TB6560AHQ data sheet I can account for 6 of the 7 Red DIL switches on the driver board

do all the 4 stepper drivers have the switches set the same way ?

if all 4 drivers are set the same way then the current will be about 2A
and you will need to fit 2K0 resistors to the Gecko G540 9 pin plugs

depending on the manufacturer ,
various stepper motor data sheets I have looked at indicated the motors can run at 70 or 80 degrees C - too hot to hold your hand on !

john

[timsisson]

Hi RaptorZ... I have the exact stepper drivers in my China 3040 CNC..... The driver board for my 'A' axis just died after a couple of weeks of using the machine. I'm trying to get the company I purchased from (eBay seller) to replace it under warranty but they (predictably) won't reply to me.

Questions for all the experts out there... Do any of you know of a place where I can purchase a replacement driver board (TX14207)? If not, what's the chance it's the TB6560AHQ chip that's burnt? I can get those on Amazon and it's easy enough to replace it. The other alternative (of course) is to just go with a higher quality board but then I also have to rewire the controller which i'd prefer to avoid. I'd appreciate any advice anyone has..

Thanks...

[john-100]

I have not seen a TX14207 for sale

have you had a look at this cnczone post about the infamous TB6560 boards :-
https://www.cnczone.com/forums/gener...-software.html

if you replace the TB6560 IC check the two 0.22 ohm resistors used for the current sense

John

[timsisson]

HI John,

Thanks for the guidance... I read the article on the TB6560... Point well taken. Unfortunately, I have 4 of these drivers in my Controller (x4 TX14207's)... One's already done... Based on what I read, my best bet is to find a good reliable driver board with a similar footprint and begin replacing them as they go out. Any suggestions on a reasonable budget?

[timsisson]

As a follow up - I've done some research and seems some like the Leadshine AM882... I'm still researching because i want to avoid the TB6560HQ chips and most all of the boards I've researched have them... This is a pic of the i'm considering... That said, the boards I am using now (TX14207) have three connections... #1 - Motor outputs (x4 leads), #2 - Power Input 12v (Pos and Neg), #3 - Cable from the RnR controller card (3 Leads - Red, Blue and Black)... I'm not sure how this translates to the AM882 as it has the same connection points for the Motor outputs and motor power but it has many more inputs from the controller card.... Is this board compatible with my unit?

[john-100]

the photos of the TX14207 I have found on the web show a 3 pin connector for a common +5V , step & direction connections
but you can see the PCB can be fitted with a 6 way terminal block


the top left hand corner of this wiring diagram has the connections for the TX14207
Attachment 388954

John

[timsisson]

John,

You're a Saint! Thanks for all this detail... One question is: Why are the 'Z' axis A+/A- pins reversed? It's indeed how my controller/drivers are wired but was curious why...

[john-100]

a good question
reversing 1 pair of wires to 1 coil will reverse the direction of the motor

but why they did not reverse the motor in Mach3 I do not know
( although it makes the default mach 3 direction setting correct for all axis )

John

[timsisson]

Very good... I get it now.

So - A little more research on the TX14207 driver. It has two LED's right next to the signal input pins. Red and Green. With regard to the TB6560 issues where you need to apply the +5v first and let the power stabilize before applying +30v (+/-) power for/to the Steppers; I've noticed that the RED LED only illuminates on power up of the control box. They stay red (on all four driver boards) until I send a movement command to any 'one' stepper motor - then they all 4 go green. I'm going to test and see if this particular driver card is preventing power to the steppers on startup (red LED), as Toshiba intended, to prevent "letting the magic smoke out of the TB6560 chip" issue... I'll let you (all) know what I find out.

If this is the case, I have a little more confidence in the TX14207 board. And - The seller has agreed to send me a replacement board as well...

Thanks again for taking the time to assist me... Your help has been invaluable... I just hope I can contribute some day!!!

[john-100]

looking at the TB6560 data sheet the maximum motor supply is 34V
some kits use a 24V supply that limits the maximum speed you can step but helps the TB6560 survive
others use a 36V supply that contributes to the TB6560's bad reputation

the TX14207 board has 4 LED's
2 green LED's :-
5V power on
& direction

2 red LED's :-
one connected to the TB6560 protect pin output
and a second connected to the 20 pin gate array logic IC ( not sure could be a fault indicator)

[timsisson]

Quick update... So I tested and found that power is indeed still going to the steppers even tough the GREEN LED is not lit (RED Only)... So my theory didn't pan out. That said - My controller powers the Stepper Boards w/ 24v DC (not 30v plus)... So maybe my TB6560 may hold up... Time will tell...

[john-100]

the switching 5V regulator used to power pin 20 of the TB6560AHQ on the TX14207 board

[wendtmk]

Uh guys, this is the Gecko forum, not the Stepper Motors/Drive forum where the TB6560 drives are discussed.

Mark

[timsisson]

Sorry... A quick question turned into a bit of a conversation...