RedLion Graphite & Siemens PAC 4200

[M0Dark]

I have a Red Lion Graphite HMI running Crimson 3 which I am trying to get to display several variables from a Siemens 7KM PAC 4200 Power Meter. Both are capable of Modbus communication over TCP/IP and are connected.
I know that all the hardware is correct as the Siemens Meter has just replaced a Socomec DIRIS A30 meter which worked perfectly and communicated with no issues.
However I cannot get anything out of the new meter to display.

I have the Network Configuration on the Redlion set to Manual with settings:
IP address: 192.168.1.20
Net Mask: 255.255.255.0
Gateway: 0.0.0.0
DNS: Disabled
Full Duplex: Enabled
High speed: Enabled

I have the Network Config on the PAC 4200 set to
IP address: 192.168.1.50
Subnet: 255.255.255.0
Gateway: 0.0.0.0
DNS: Disabled
TCP Port 502

I have the Protocl on the Redlion set to Modbus TCP/IP Master, and the device settings for the PAC 4200:
Primary IP: 192.168.1.50
Fallback IP: 0.0.0.0
TCP port 502
Unit No. 1

Ping Holding Register: 1
Ignore read Exceptions: No
Link: Dedicated
ICMP ping: Disabled
Connection Timeout: 5000 ms
Transaction Timeout: 5000 ms

Word Order (Long & Real): High then Low

Register Writes: all off
Frame Reg Limits
Code 03: 32
Code 01: 512
Code 02: 512
Code 16: 32
Code 15: 512
Code 04: 32

Spanning Reads: Enabled
Transactional Writes: Enabled
Preempt Other Devices: No
Favor UI Writes: No
Comms Delay: 0 ms

All of which apart from the Main IP are the same as the working DIRIS.

Then I have assigned data tags to the frequency from the device:
On the Diris the Modbus table gives an address of 50526 for this and a data type of U32 (Unsigned).
To get this value to display on the red lion the Tag settings are:
Source Device: Diris. Address Data Item 4 - Holding Registers. Element 50527
Data Type: Word as Long

The Modbus table for my Siemens PAC 4200 doesn't give an address, it gives an offset of 55. and states the data type as float.
From this I have Set the Tag setting to:
Source Device: PAC 4200. Address Data Item 4 - Holding Registers. (Also Tried 3 - Analogue Inputs)
Element 55 (also tried 54, 55 & 56)
Data Type: Word as Real (also tried Word as Long)

I am at a loss as to why I cannot get any value to display, does anyone know what I have done wrong?

 

[OkiePC]

Create a flag tag in Crimson and for its source, type in:
IsDeviceOnline(PLC)
but substitute the device name you gave your power meter inside the parenthesis where I have PLC.

If you want, you can assign the format as two state and make the Label "Power Meter Comms" with the ON State as "Okay" and OFF state as "Lost".

Drag that tag onto a page and update the HMI. Until you get that tag to show comms are okay, you will get nothing useful. That function is dependent on the Ping Holding register being enabled for Modbus protocol devices, but according to your notes, it should work. Basically, using the ping holding register, the driver periodically reads that holding register to see if there is a response to set "IsDeviceOnline()".

I have had a few odd devices that required me to limit the number of words or bits I can read at one time in order to work properly. Those were serial devices (Modbus RTU, not TCP). I have also had devices that didn't work well with Spanning Reads enabled. With Spanning reads enabled, if your application asks for holding register 5 and 10, for example, the HMI driver will ask for 5 through 10 in one block, but if one of those doesn't exist in the target device, it may balk or throw an exception.

I have also worked with several devices that needed me to slow down the communication speed. The Red Lion will poll extremely fast and if the target device can't handle it, it might flake out and quit communicating. You can slow the driver down on the Communication page by adding a value to the Comms Delay. 1000ms should be more than enough as a test.

If making those adjustments does not work, make a dummy application with only a single tag and make it read Holding Register 1 (400001) Word as Word to just try to read that single 16 bit word as an integer. Don't have any other tags for that device in the application. If that still doesn't work and all the comms settings are for sure correct, change it to Word as Long so it reads two 16 bit words. Some devices might not like it if you try to read half of a 32 bit data type and won't respond.

I say all this without looking at the manual for your power meter, so if you post a link to that, you might get better help.

 

[M0Dark]

Thanks OkiePC,
Setting Spanning Reads to Disabled and adding a 1000ms delay fixed it.