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View Full Version : What is a decent spindle relay ?



John11668
22-08-2020, 11:58 AM
Following on from my recent query about unwanted spindle pulsing, I will take advice from there and get a separate spindle relay.
I would like one which is robust but gives me the opportunity to vary speed so will need to provide a 0-10v signal to the VFD.

I did buy a CP0-10V https://www.cnc4you.co.uk/Breakout-board-CP0-10V-CNC-4-Axis-with-Charge-Pump?search=cp but it did not live long.
I don't know whether it failed , or whether I broke it , but if I ask them then it is bound to be the latter. Not sure if I would fancy the same again.

What other options would folks suggest ?

Maybe as part of the discussion I will raise an issue which occurred yesterday when VFD came up with 0PF2 (lost phase fault) whenever I stopped the spindle . It was stuck at 99.9hz and my manual pot seemed to be reluctant to turn it down. I reckon the pot had gone on the blink and by working it back and forth a bit I got it to control again.
Maybe there is a better solution than a cheap wire wound pot????

JAZZCNC
22-08-2020, 07:01 PM
Following on from my recent query about unwanted spindle pulsing, I will take advice from there and get a separate spindle relay.
I would like one which is robust but gives me the opportunity to vary speed so will need to provide a 0-10v signal to the VFD.

Hi John, Maybe you misunderstood when I said I use a better quality relay.? It's only for the Stop/Start and not the 0-10V speed reference voltage.
You don't need the speed reference going through the relay as it's only telling the VFD how fast to spin, it's the Start/stop signal that pulses it on off.

Finder or Omron are both decent relays.

John11668
22-08-2020, 10:14 PM
I am only using the spindle relay function on the board to switch a 2 wire signal (24v) to tell the VFD to start the motor so very light duty and effectively the VFD is acting as a 3 ph., 1.5 Kw relay here .
Along with its options for spindle delay , soft start , et al

This KK01 relay started to play up on its 5v USB supply , so I had to add a 5 v PSU.
Previous BOB also from CNC4you, also fell over . so I cant use its 0-10V facility .

Is there a simple (I need simple ) spindle control relay capable of switching the signal voltage to start the spindle motor , then provide a 0-10V variable voltage to speed up and slow down the spindle as required .

If it comes down to it I can stand up and hit the start button and twiddle the pot to increase / lower the revs, but as I normally have my lazy backside on my bar stool, it would be nice to be able to control it from the keyboard :cheerful:

John11668
23-08-2020, 02:57 PM
Hi John, Maybe you misunderstood when I said I use a better quality relay.? It's only for the Stop/Start and not the 0-10V speed reference voltage.
You don't need the speed reference going through the relay as it's only telling the VFD how fast to spin, it's the Start/stop signal that pulses it on off.

Finder or Omron are both decent relays.

Presuming the BoB relay is up to the task of starting the VFD , then where do I take my 0-10v signal from ?
Does UCCNC facilitate that?

johngoodrich
23-08-2020, 05:50 PM
0-10v will still come from the breakout board as usual

Doddy
23-08-2020, 06:38 PM
John11668 - some BoBs, though not the KK01 that you have, have an onboard PWM - to 0-10V converter, and within UCCNC you'd specify the pin that this function is attached to, and then UCCNC would generate a pulse-train that the BoB would then convert to 0-10V for spindle speed. Unfortunately, as mentioned the KK01 doesn't support this function. Ironically, the more typical $5 chinese BoBs tend to.

John11668
23-08-2020, 08:00 PM
Right so what is the difference between this
https://www.cnc4you.co.uk/Breakout-Board-and-PSU's/Breakout-board-CP0-10V-CNC-4-Axis-with-Charge-Pump

And this
https://www.ebay.co.uk/itm/CNC-5-Axis-Interface-Breakout-Board-For-Stepper-Motor-Driver-CNC-Mill-MACH3/291980216229?_trkparms=aid%3D1110006%26algo%3DHOME SPLICE.SIM%26ao%3D1%26asc%3D228420%26meid%3Db3093b 9a8219423e9264f76d18f48b9d%26pid%3D100005%26rk%3D5 %26rkt%3D12%26mehot%3Dpf%26sd%3D164323963661%26itm %3D291980216229%26pmt%3D1%26noa%3D0%26pg%3D2047675 %26algv%3DSimplAMLv5PairwiseWebWithDarwoV3BBEV1%26 brand%3DUnbranded&_trksid=p2047675.c100005.m1851

Apart from having to wait a couple of weeks that is

Doddy
23-08-2020, 08:15 PM
To be fair, the £50 includes a charge pump. If you don't know already - a charge pump requires a constant pulse-train from the controller (PC) before it enables the spindle relay... to avoid inadvertent signals from the PC inadvertently switching the spindle on... ta da!, that's the real solution to your problem.

Anyway, ignoring the charge-pump functionality, the boards are functionally similar, though as you might expect the £50 card a bit more refined, although that one in particular looks very similar from a component count to the Chinese board. Both offer a 0-10V PWM driven output.

Doddy
23-08-2020, 08:26 PM
Of interest - your old CP0-10V - you said that didn't last long. What happened to it?, how did it fail? And do you still have it? There's limited interest in a dead board but it's an expensive board to replace - if you wanted me to have a quick look to see if there's anything repairable on the board I could take a look for you if you cover postage.

johngoodrich
23-08-2020, 09:33 PM
i have one of those cheap ebay ones in your link and that does exactly what you want. i have it linked to my uc300eth and it turns the spindle on and off and also controls the speed through mach

John11668
23-08-2020, 09:44 PM
Of interest - your old CP0-10V - you said that didn't last long. What happened to it?, how did it fail? And do you still have it? There's limited interest in a dead board but it's an expensive board to replace - if you wanted me to have a quick look to see if there's anything repairable on the board I could take a look for you if you cover postage.

Would be quite happy to send for your inspection doddy. PM your contact details . Basically one day it stopped responding to a power supply .Led no longer came on

John11668
23-08-2020, 09:51 PM
i have one of those cheap ebay ones in your link and that does exactly what you want. i have it linked to my uc300eth and it turns the spindle on and off and also controls the speed through mach

I am sure I can handle the lack of charge pump. I may order a couple of the cheap chinese ones .
Do none of the cheap ones have a charge pump facility.

It isnt the cost off the CP1-10V which hurts , It is the cost of postage , plus vat which leaves little change from £80
Then you dont know if you are being taken for a ride , and the support can be a bit abrupt if you ask any questions rather than accepting what you are told blindly.

Clive S
23-08-2020, 10:16 PM
Right so what is the difference between this
https://www.cnc4you.co.uk/Breakout-Board-and-PSU's/Breakout-board-CP0-10V-CNC-4-Axis-with-Charge-Pump

And this
https://www.ebay.co.uk/itm/CNC-5-Axis-Interface-Breakout-Board-For-Stepper-Motor-Driver-CNC-Mill-MACH3/291980216229?_trkparms=aid%3D1110006%26algo%3DHOME SPLICE.SIM%26ao%3D1%26asc%3D228420%26meid%3Db3093b 9a8219423e9264f76d18f48b9d%26pid%3D100005%26rk%3D5 %26rkt%3D12%26mehot%3Dpf%26sd%3D164323963661%26itm %3D291980216229%26pmt%3D1%26noa%3D0%26pg%3D2047675 %26algv%3DSimplAMLv5PairwiseWebWithDarwoV3BBEV1%26 brand%3DUnbranded&_trksid=p2047675.c100005.m1851

Apart from having to wait a couple of weeks that is

About £40. With it you do need a 12-24V power supply + a 5V one as well although you can power the 5 volts from a usb but personally I don't do that.

I have used plenty of them without trouble

Doddy
28-08-2020, 07:39 AM
Okay - bit of info about the CP0-10V board. John was kind enough to post this to me to eyeball.

The power-supply stage is a LM2576HV-12 device, designed to take a DC supply from 14-60V to provide a switched-mode regulated board supply of 12V for the analogue subsystem. A local linear 7805 provides machine-side logic supply, and an isolated DC-DC convertor provides a PC/Parallel interface supply. This last bit is kind of interesting and intended to isolate the ground from PC to machine. There's no substantial filtering.

John's board - it is the LM2576HV-12 device that's failed. The device is obsolete - and difficult to source. There's reference on Google to dodgy relabelled devices coming out of China. It is pin compatible with the non-HV variant, or the more modern LM2596, however the latter requires an inductor change on the board.

View from the bottom of the board,

28740

It's another board that requires pin 18 and pin 25 of the parallel port to be shorted through the parallel port of the connected PC, or controller interface, to power up the PC-side interface. Notionally a safety interlock, it's necessary to be aware of this when integrating a non-PC based controller solution. I hate these - and would chose to hay-wire this to remove the "protection". However - it is what it is.

The board does provide a charge-pump interface, powered from the board rails. This influences the ENA outputs and relay outputs. Testing with a 12.5kHz source confirms this operation. There's a slide-switch to disable this function if necessary.

Why did it fail? Hard to guess. The 2576 is a robust design - with overcurrent, over temperature protection. I'm not convinced of any suggestion of user-error - it's more robust than the interfaces presented by the board (they'd burn out before the 2576 is damaged). Handling error ESD during board assembly?, manufacturing fault with the device itself are both possibilities. Voltage spikes presented to the input of the device by a common PSU driving the stepper drivers - that's a possibility, or possibly grey supply chain and illicit device is a distinct possibility. But that's all conjecture. What I can say is the device was as dead as the proverbial parrot.

So, solution agreed with John was to remove the LM2576HV-12 and short the input/output pads on the board. The board therefore now requires a regulated 12V supply to operate. It's a simple job to replace with low-voltage variants of the 2576, or the pin-compatible 2596, but John's use-case requires a >40V tolerant supply, which these devices do not support.

28741

Not a good picture, but shows that the power LED is now on. I've tested all digital outputs to the axis step/dir and ENA pins and relay with/without charge pump. All satisfactory.

John11668
29-08-2020, 09:45 PM
Nice work Doddy and thanks for your efforts.
I will get the required power supply, what current rating will cover my needs?
Should I also have a 24 v supply to cover other potential requirements?

I dont think that I flashed it or spiked the card but i suspect I would have a tough job convincing CNC4you that it was a simple warranty failure
But I now know I can get something adequate from the far east for less than £6 inc carriage and vat which realistically is far less than their P & P on a replacement part.
While initially they were good for support , they now seem to get a bit uppity if you ask further questions so you feel reluctant to approach them.

Who needs them anyway when the support here is so good.