Messages

1

Modbus / ModBus Output

« on: April 08, 2014, 04:54:21 PM »

Hi guys,

I have full comms to my VFD via Modbus, but I have an issue that is causing heartache!

My VFD accepts reading of registers by using Modbus function code '03' and writing of registers using function code '10'. Mach3 reads using the 03 code with no problem and can write 2 or more registers by using code 10.

I really need to write  a single register - but when I do Mach3 uses function code '06' eeeek is there any way of writing a single register using function code '10' (which the VFD accepts).


earle

2

Modbus / Modbus Spindle Help

« on: April 07, 2014, 12:42:45 PM »

Hi,

I have a Chinese 6040 Mill, it has a NowForever D100 VFD that drives a 1.5Kw spindle!

Using Mach3 the whole setup works fine but I would like to automate the start/stop/rpm of the spindle. I currently use the keypad to control these functions.

I have used  'kmtronic Modbus tester' to send correctly formatted codes for both read and write commands to the vfd to start the spindle, change the spindle rpm and stop it, and it works fine.

I have looked at the various documentation for Brains/vb etc etc and at first glance cant see the immediate way forward. But I think I need to get the basics working from Mach3 before proceeding...

Issue 1. I have enabled Modbus in 'Ports and Pins' and used 'Test Modbus' to read holding registers from the vfd and this works fine and returns the correct results, but I cannot write to any holding registers, 'Test Modbus' returns a 'illegal data value' when I want to write the same value back!

Issue 2. When I enable the 'Modbus Plugin Support' the 'Test Modbus will not read or write values and returns a 'Receive Timeout'.

The VFD spindle control registers are in a group with an address of 900H as per the manual below.

Any help or pointers would be an amazing help, as I am a bit in the dark at the moment.

Thanks, Earle