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artmin
20-02-2016, 04:16 PM
I have a Heiz High Z 1000T which I use daily and it has proved as solid as a rock for the last 6 years. I was getting fed up replacing the Kress spindle every year so I have started to convert over to a water cooled VFD. Wanted to add a no voltage contacts for switching the VFD (DCM+FOR) so I thought the neatest way would be to add a 12v relay with volt-free contacts inside the controller and piggy back the 12v relay that switches the existing 240VAC supply to the Kress, which would then be left redundant but still there if I needed it. Simples, I thought & now the trouble has started :nightmare:

I have now removed my additional relay to try and get the machine to work again, though I think something else must have been upset. Is was the PSU board that I had removed and took lots of photos to ensure that the leads were reconnected correctly. What is happening now is when the controller is connected to the steppers and powered up, everything seems normal and the steppers are holding. When I connect the 25pin PP cable to the PC port and powered up, the steppers all make a horrible noise and are creeping slightly. It does this only when connected to the port of the PC (any PC in fact as I tested it with my backup PC) but it is fine when the 25pin cable is just connected at the controller end. Does anyone have any ideas please as this is now way beyond me.

17643

The rough rectifier mod at the top of the photo was made years ago, after the solder kept melting on the diodes of the rectifier OP, but that has been faultless since.

Many thanks in advance,

Gavin

cropwell
20-02-2016, 05:35 PM
My first thought is that electrical noise from the VFD is triggering false stepper pulses. Earthing and shielding should be checked.

artmin
20-02-2016, 06:04 PM
Ahh yes, I know what you mean and I have planned ahead for that, but I still have the Kress installed. It happens when the 25pin cable is connected to the PC (at the PC end) whether or not the PC is on. I also tried it in the standard printer port & same thing happens. Also happens with my spare PC.

It does look like electrical noise and it's on all axis. I just can't see what has changed.

cropwell
20-02-2016, 06:19 PM
Have you got a spare printer cable to try ?

artmin
20-02-2016, 06:34 PM
I did have a rummage for another to test it, but I'll have to dig deeper.

artmin
20-02-2016, 07:39 PM
Unfortunately it's not the cable. I just managed to fit the ribbon on the control board straight into the back of the parallel port and it's still doing the same.

Is there anybody in the UK who takes this kind of repair job on or is it better to ditch it and build a new controller with bits from Zapp? I was just very happy with how stable the system was. I could throw half a million lines of code at it and it would take it in it's stride.

BernieNUFC
20-02-2016, 09:07 PM
I could give you the details of a company we have used for 20 years that do repairs down to component level and hvae made boards etc for us, not sure on how it stands of advertising tho as i cant pm you

malc

ptjw7uk
21-02-2016, 12:34 AM
Sounds as if somethings not connected right with the power supply, check with a volt meter and then check again!

Peter

Clive S
21-02-2016, 08:42 AM
I have a Heiz High Z 1000T which I use daily and it has proved as solid as a rock for the last 6 years. I was getting fed up replacing the Kress spindle every year so I have started to convert over to a water cooled VFD. Wanted to add a no voltage contacts for switching the VFD (DCM+FOR) so I thought the neatest way would be to add a 12v relay with volt-free contacts inside the controller and piggy back the 12v relay that switches the existing 240VAC supply to the Kress, which would then be left redundant but still there if I needed it. Simples, I thought & now the trouble has started :nightmare:

I have now removed my additional relay to try and get the machine to work again, though I think something else must have been upset. Is was the PSU board that I had removed and took lots of photos to ensure that the leads were reconnected correctly. What is happening now is when the controller is connected to the steppers and powered up, everything seems normal and the steppers are holding. When I connect the 25pin PP cable to the PC port and powered up, the steppers all make a horrible noise and are creeping slightly. It does this only when connected to the port of the PC (any PC in fact as I tested it with my backup PC) but it is fine when the 25pin cable is just connected at the controller end. Does anyone have any ideas please as this is now way beyond me.

17643

The rough rectifier mod at the top of the photo was made years ago, after the solder kept melting on the diodes of the rectifier OP, but that has been faultless since.

Many thanks in advance,

Gavin

Ok then where are the lots of photos? Can you be more specific in what is wrong? Do you have a schematic?

artmin
21-02-2016, 01:48 PM
I have found the controller schematics here: http://www.cnc-router-store.com/wp-content/uploads/stepcontrolhy_eng.pdf

The voltages all seem good at the 5V 12V +37V outputs, though the 37V is reading 33.5V

What I have discovered is if I shake the PC end of the PP cable in the air, some of the axis move. :disturbed: When plugged into the computer (off & on) the motors are squealing and the controller relays for the spindle & coolant are buzzing, sometimes. When I remove the jumper wire from the controller back to the relays on the power board they stop okay so seem to be getting a pulsing signal from the computer end. When the PP cable is disconnected from the computer the motors are fine.

I delved into the PC and I couldn't find the PP card in the device manager and pulling it out & replacing it with a boot in between, it's not recognising it. So I plugged into the onboard PP and changed the port address and the motors at least appeared to be responding to the jog controls, though not moving (pitch can in the sound). The sleep function appears to be working too.

I swapped over to my spare pc which only has an onboard PP and I could get the axes to move roughly in the right direction, but with lots of noise & judder. They motors still squeal when stationary whether or not the PC is powered up.

I have just ordered a new 25pin card & cable as a starting point. Does this sound like an issue with the PC now or do you still think that it could be controller related. I have checked for anything that could short out the control boards and all look clear. I gave it a light blast with the airline too.

Robin Hewitt
21-02-2016, 02:28 PM
I usually get completely the wrong end of the stick but let's have a go.

If you fitted a relay and everything went wrong even after that relay was removed...

This would suggest the relay had no protection diode and what ever you were using to drive the relay also drove the thing that no longer works.

You probably know about protection diodes but just in case. Current flows through the relay coil. A semiconductor device attempts to break the electrical circuit. The coil inductance requires that the current continues to flow, the volts go through the roof, the break down voltage of the semiconductor is exceeded and the magic smoke escapes. A protection diode across the relay coil allows the current to flow back through the coil until it dissipates.

artmin
21-02-2016, 03:14 PM
Thanks Robin, never heard of protection diodes but there is a diode beside each relay on the power board:

17657

I had taken leads from the coil pins of the existing relay on the underside of the power board to supply my additional relay. Maybe this extra load could overload the circuit, but the relays are still working okay using the manual override switches on the front panel. I didn't notice or smell any smoke at any point. Saying that I was flapping around at this point:stupid:. Can't see any burn't components anywhere.

artmin
21-02-2016, 03:22 PM
Quick question. Does the 25pin port from the PC supply the 5V signals towards the controller only, or does the controller also have to send 5V signals back to the PC. I know that limit switches at least have to send a signal back in some form.

cropwell
21-02-2016, 03:58 PM
The PP pins send and receive 5v signals depending on the pin. What worries me about this controller is that it has no opto isolation and so your computer is vulnerable. You should be glad that you have a PP card as it is easier to replace than a motherboard. Everything points to a spike going back to the PP. The pinout diagram shows the capabilities of each pin. How they are used depends on the controller. If it were my controller, I would replace the driver board with a BoB and three drivers, but it is a lot of work to cure what could be a simple fault.

http://i928.photobucket.com/albums/ad126/vicrider_photos/parallel_port_pinout.jpg

artmin
21-02-2016, 05:13 PM
Thanks for that, I am hoping that it is just the PP card. Hopefully I will receive a new one by Tuesday. I remember when I could have popped over to PC world and picked one off the shelf but times seem to have changed.

Replacing with a bob and drivers is my backup plan if all else fails. It is exactly as you put it so well: A lot of work over possibly over a simple fault. If I did end up going that way, with 2 steppers on the X axis, could I get away with 3 drivers or would I need 4?

Cheers,

Gavin

magicniner
21-02-2016, 05:44 PM
+1 on the voltage spike possibility


The PP pins send and receive 5v signals depending on the pin.

Or 3.3V for most modern cards and laptops.....


I remember when I could have popped over to PC world and picked one off the shelf but times seem to have changed.

Maplin still stock some but I'm not sure what bus types for and what voltage data levels.

- Nick

cropwell
21-02-2016, 06:50 PM
+1 on the voltage spike possibility



Or 3.3V for most modern cards and laptops.....



Maplin still stock some but I'm not sure what bus types for and what voltage data levels.

- Nick

The PP cards generally are 5v logic.

Sorry, you would need 4 drivers if you have a slaved X axis, I wasn't paying attention to the actuals, just the principles.

What operating system are you using on the PC? Most of these PP cards have very old drivers. They work OK up to XP generally, but no later.

I have got one of the PCI socket (not PCI express) PP cards (dual port) sat in a drawer and several new LPT leads, if you get stuck.

Nick, Maplin used to be good, but it is just a toyshop now. Most of the gear you can get cheaper by up to 2/3 (that's a quarter of the price in pub talk) , though Maplin do take stuff back more readily.

Cheers,

Rob

magicniner
21-02-2016, 07:01 PM
The PP cards generally are 5v logic.


Nope, that used to be the case but modern hardware can be running anything down to 2V Signal High.

- Nick

cropwell
21-02-2016, 08:43 PM
Nope, that used to be the case but modern hardware can be running anything down to 2V Signal High.

- Nick

Modern they aint. The cards with the Moschip MCS9805 or 9815 use 5v logic, and they are in the majority of add-on PP cards on the market.

Rob

artmin
21-02-2016, 08:48 PM
Thanks Guys and thanks Rob for the offer of the card if I get stuck.

I'm running XP still on the CNC but it's that WinPC-NC Economy that I'm using. The PCI card was churning out 5V.

Hopefully the new card will work and get it up and running, but I know that the old controller isn't the best. I would rather have a seperate PSU, BOB & drivers, so I'm thinking about building a second controller with 9 pin d sub OPs that will connect straight up to the machine and hold it as a backup until I can get time to crossover. I would also prefer to move over to Mach but I'd rather get a bit of practice on it first before going at it full tilt. I can't find anywhere on WinPC-NC to change the axis driver pins to match a BOB if I needed to. Spindle, coolant, tool sensor etc can be nominated but not the essentials it seems.

I just have to wait for the postman now!

Cheers,

Gavin

magicniner
21-02-2016, 09:01 PM
Modern they aint. The cards with the Moschip MCS9805 or 9815 use 5v logic, and they are in the majority of add-on PP cards on the market.

Rob

Useful info, any big brands to look out for or just generic ebay stuff?

JAZZCNC
21-02-2016, 09:19 PM
If you have tried on another PC then you have elimnated the PC and it should have worked so this suggests you have other issues.?
Doesn't matter if PC was old, infact often better being old as the PP will be 5V not 3v.

I would start again removing anything that isn't required and re wire. Then Fresh install of software on Fresh PC if possible.
If still giving trouble then chances are you have damaged chips or something on the control board.

In this Case I would just scrap the whole lot and replace with modern gear.

cropwell
21-02-2016, 09:40 PM
Useful info, any big brands to look out for or just generic ebay stuff?

Nick, I don't buy dozens every day. All I remember is that the last one I bought was about 7 and was 'Generic Chinese' - that's the only brand I could get at a decent price. Startech are charging 4x that.

Drivers are a sod to find if you lose the disk, you have to hunt t'Interweb based on chip or hardware id and try several before you find one that fits.

Rob

cropwell
21-02-2016, 09:46 PM
If you have tried on another PC then you have elimnated the PC and it should have worked so this suggests you have other issues.?
Doesn't matter if PC was old, infact often better being old as the PP will be 5V not 3v.

I would start again removing anything that isn't required and re wire. Then Fresh install of software on Fresh PC if possible.
If still giving trouble then chances are you have damaged chips or something on the control board.

In this Case I would just scrap the whole lot and replace with modern gear.

The only chips on the control board are the drivers. If the input stages are bolloxed then I personally would go with the last idea as the PC seems to be very vulnerable. Case and power supply seem OK though :whistle: although the case may be a little small for 4 drivers.

Cheers,

Rob

i2i
23-02-2016, 04:06 AM
Make sure the ground of the driver board is connected to the ground of the parallel port.

artmin
23-02-2016, 01:50 PM
Make sure the ground of the driver board is connected to the ground of the parallel port.

Checked the ground and it is okay. Unfortunately I think JAZZCNC is correct. I installed the new PP card & lead and it's doing the same rubbish.

I have contacted Heiz and they have offered me an upgrade to the new Zero3 controller. It is available off the shelf in Germany for 360 Euro + VAT (19%) + shipping. It is a direct plug in replacement, so for the sake of speed & my sanity, I'm going to pull the trigger on it.

I'd still like to rebuild the old unit with CW5045 drivers & BOB as a direct plug in backup, install Mach on the spare PC and get learning.

Many thanks for all your help!

Gavin