Topics

1

Support Questions / Comms Failure Alarm on Modbus TCPIP

« on: February 11, 2016, 04:15:49 AM »

Firstly I want to say a huge thanks you to Archie for a great programme and for making it free and accessible.  Secondly I want thank Archie and rbelknap for helping me out with developing my first Advanced HMI application.

With their help I have almost finished but there is one further thing I would like to try and implement.  This application is to create a simple test interface to connect to two PLC’s with separate comms set ups.

I would like to be able to light a basic indicator if comms to either of the PLC’s should fail.

I read on the other thread the two suggestions one of using a Watchdog Timer and the other frankly I didn’t understand at all.

I well understand the principle of a Watchdog but in practice how would you implement this on the HMI side?  Does a timer have to be created and controlled in VB?  If so any hints on how to do this?

Or, considering that I am using ModbusTCPIP is there a better (easier?) solution I can consider?

See below for my (almost) finished HMI – you can see the orange indicators that I would like to illuminate in the case of a comms. failure.

Once again….any help offered is very much appreciated!

2

Support Questions / Digital Panel Meters and changing the display count

« on: February 10, 2016, 07:50:18 AM »

Hi

Apologies again for yet another newbie question....

I have a couple of Digital Panel Meters that are reading values and displaying nicely from my PLC.  Problem is the timers in the PLC start at the present total value and then decrement to 0.  I can get the meters to display this quite nicely.

However I would rather have the meters count up from zero to the present total - I am assuming I need to do this through code?

So I assume I need to get the preset total for the particular timer and then subtract the current timer count to do this and display the result on the meter?

Can anyone advise the correct VB syntax to achieve this?

Thanks again in advance

3

Support Questions / One HMI & Two PLC’s simultaneously on MODBUS TCP

« on: February 08, 2016, 10:47:04 PM »

Can anyone please advise if it is possible to have a single control (PB, etc.) from a single HMI that can write to the same address in two different PLC’s (different IP addresses) simultaneously?

In addition can I have two display controllers (i.e. digital panel meter) display values from each PLC simultaneously on the same HMI?

I am using MODBUS TCP comms.

Thanks in advance!

4

Support Questions / MODBUS TCP/IP

« on: February 03, 2016, 09:42:50 AM »

Hi there

Can someone please help me out with addressing a MODBUS TCP/IP slave device from Advanced HMI?

I have been able to set up comms and put pushbuttons and indicators on a basic HMI but when it comes to putting the PLC address in the properties of the HMI control item I am a bit lost.  I am not clear on what format  the MODBUS address should be?

I keep getting errors on the comms - what is the correct format to put the MODBUS address - do I need the MODBUS control code as part of the address.

Any help would be very much appreciated!

Thanks in advance....