Messages

251

General Mach Discussion / Re: Bad BOB???

« on: February 17, 2011, 08:08:24 PM »

Hi,

You haven't provided information about what stepper drivers and other components you are using.  A bit more info whould be helpful.

I sell, a robust and simple to use breakout board.
http://homanndesigns.com/store/index.php?main_page=product_info&cPath=22&products_id=59

Cheers,

Peter.

252

General Mach Discussion / Re: G540 / Smooth Stepper and an E Stop

« on: January 24, 2011, 06:13:20 AM »

If the SS loses communications then it will not run your drives.
Also you are falling into the trap of thinking the chargepump is a safety device, as Peter has mentioned that is not its intended purpose and it should not be thought of that way.
Hood

253

General Mach Discussion / Re: G540 / Smooth Stepper and an E Stop

« on: January 24, 2011, 04:15:40 AM »

Hi,

This is a situation where you don't need to use the Charge pump facility on the G540. You don't need it as you are not driving the G540 from a parallel port. Switch it to the OFF position.

Keep in mind that the charge pump was provided due to the fact that when a PC boots, the outputs of the parallel port will twitch during bootup. This has the undesirable effect off momentarily switching on outputs such as spindle relays, and issuing spurious step signals to drives etc. By having Mach3 generate a chargepump signal when running, breakout boards cab disable outputs until Mach3 is up and in control.

Since the SmoothStepper knows when its communicating with Mach3, the chargepump signal has no use in this setup, so turn it off.


While we are talking about the chargepump signal, a note relating to using it with parallel port setups.

Under the general config in Mach3 there is a checkbox labelled "Chargepump On in EStop". You should always check this. There is no situation that I can envisage that you would want to use the chargepump for anything other than an indication that Mach3 is running.

And further, relying on the chargpump for anything else other than an indication that Mach3 is running (and not necessarily running correctly) is dangerous.




Cheers,

Peter.

254

Modbus / Re: Hitachi SJ200 and ModBus Control Problems

« on: January 19, 2011, 09:55:50 PM »

Hi Greg,

Good to hear,

Do you want to publish your setup and brains, etc,

Cheers,

Peter.

255

Modbus / Re: Hitachi SJ200 and ModBus Control Problems

« on: January 19, 2011, 03:28:19 AM »

Greg,

Presumably 0000h is reserved as it can't be accessed.

Cheers,

Peter.

256

Modbus / Re: Hitachi SJ200 and ModBus Control Problems

« on: January 19, 2011, 01:37:52 AM »

Greg, Skippy,


You you need to read the Modbus specs to understand what is going on, but to summarise there are 2 types of representing Modbus addresses. They are;

• PLC Addresses (Base 1)
• Protocol Addresses (Base 0)

They are different ways to represent the same data.

Protocol Addresses Base 0 addresses are the actual data offset. So for coils address 0 accesses the data for the first coil. address 1 accesses the data for the 2nd coil, etc.

For PLC addresses Base 1, Coil addresses start at at address 0001.



And.... Mach3 uses Protocol addressing base 0. Therefore, to access address0001 on the X200 you use the address 0000 as that accesses the first coil.

Clear as mud?




Anyway, that's what I think is going on. The attached image from the spec shows the mapping from protocol to PLC addresses.

Cheers,

Peter.

257

Modbus / Re: Altivar 12 Modbus TCP IP

« on: January 16, 2011, 03:38:35 PM »

Dietmar,

The RJ45 connector on the VFD is for a Serial Modbus connection via RS485, not TCP/IP.

So you cannot control it via Modbus TCP/IP directly, you would been a Ethernet to RS485 converter.

Cheers,

Peter.

258

General Mach Discussion / Re: PWM Spindle Control using Mach3 - How I did it

« on: January 12, 2011, 07:25:36 AM »

Chris,

The output you are using pin 14 on port 2 uses the same supply as pin 1, 16, and 17 on port 2. So if you try to use a VFD or DC motor controller such as the KBIC-120, with a non-isolated analog control voltage input, the 0V terminal is likely to be at supply((110V) - 10V. If that is the case, there will be serious damage if these other inputs are referenced to chassis ground.

If the VFD or DC motor controller has an isolated or ground reference input as is the case with your Danfoss VFD, then yes your circuit will work.

You should still make it clear that your circuit will not work with non-isolated VFD or Motor controller inputs.

Cheers,

Peter.

259

General Mach Discussion / Re: PWM Spindle Control using Mach3 - How I did it

« on: January 12, 2011, 01:36:30 AM »

Hi Chris,

Unless I've understood incorrectly, There doesn't appear to be any opto-isolation in your PWM to voltage converter circuitry. If this is the case you are relying on the VFD or speed controller having opto-isolation on its input.

If your circuit is connected to a VFD or motor controller input that is not isolated from the rest of the outputs connected to the same supply, you will most likely fry whatever is connected to these other outputs.

At the very least you need to put in a warning in your documentation. Otherwise some of the novices you are trying to help wont be happy.

Better still, replace T1 in your circuit with an opto-isolator and make it clear that the Gnd and 12V supply comes from a separate isolated power supply.

Otherwise all good info.

Cheers,

Peter.
 

260

SmoothStepper USB / Re: SmoothStepper Modbus RPM DRO conflict

« on: January 11, 2011, 09:53:16 PM »

Greg,

The thread title is "SmoothStepper Modbus RPM DRO conflict". This problem occurs when there is no index sensor attached. To start talking about threading and synchronising index sensors  just isn't relevent to this thread (it's a completely different topic) and  just adds confusion.

An index sensor synchronisation is also required for threading through the parallel port. But, that's also not relevant to this thread either.

Cheers,

Peter