Polling Realflo Registers into RemoteConnect Logic Editor

[Joel_Weder]

There are currently two ways to get Realflo data into RemoteConnect and the Logic Editor within the same RTU. First, I’ll discuss configuring a Modbus Scanner in RemoteConnect. Then I will discuss how to use DFB's (derived function blocks). Typically, the Modbus Scanner method is preferred if many registers are to be polled, or if 6-digit Modbus registers must be polled. The DFB method may be preferable when only a few registers are to be polled, or if you are comfortable editing a DFB.

Using Modbus Scanner to Poll Reaflo Values
- While Offline, right-click on SCADAPack x70 Controller Settings -DeviceDTM
- Select Additional Functions, then Project Settings. This is where you’ll have enabled Realflo.
- Enable the Modbus IP Client, allowing the RTU to perform IP polling, then click OK to close this dialog.
- In the Modbus configuration area, you’ll now see the Client item. Select this.
- Click the Add Device button. Give the new Client a name e.g. “Realflo Polling”
- Enter an IP address of 127.0.0.1 (the "localhost" or same RTU that Realflo is on)
- Click OK, then Apply the change
- Expand Client by clicking the [+] and select the client just created
- Click the Add Scanners button
- Set the Modbus Data Type to Real (or as required), then enter the required register address 
- Enter the required Register Quantity (remember, two registers per Real) then click OK
- Select Automatically Create and Connect new Objects then click OK and Apply
- The new objects are assigned names such as MBUS_Realflo_REAL_4xxxx. You can change these to something more meaningful, such as Run1_FlowRate.
- Configure the new objects with appropriate Logic Variable Type e.g. T_SPx70_ADV_ANALOG.
- The objects may now be used in Logic Editor.

Using DFB's to Poll, GET or SET Realflo Registers
If you need to make use of flow run instantaneous values, or change/view Realflo configuration values, several DFB's (derived function blocks) have been provided in the "x70 Logic Function Blocks" sub-folder under Program Files (x86) > Schneider Electric > Realflo. The needed DFB may be imported into Logic Editor, then used to get the value from Realflo. One additional DFB not included in that folder is attached to this post, which may be used to poll the flow computer for a Float value.

- In Logic Editor, right-click on Derived FB Types and select Import 

- Navigate to Program Files (x86) > Schneider Electric > Realflo > x70 Logic Function Blocks. (or to wherever you saved the "getregfloat" DFB) and select the desired DFB

- Once the DFB has been imported, you may right-click on it to Put in Library for later use as well

- Next, create a logic section and in the FFB Input Assistant simply create an instance of the DFB

NOTES about the getregfloat DFB:

- If desired to poll more than one Float (Real), simply daisy-chain two or more instances. Tie the Done output of the first to the Request input of the next.

- This DFB is only able to work with 5-digit Modbus registers, not 6-digit

[tturner45]

Hi Joel, 

In older versions I remember you couldn't constantly poll Realflo and Read/Write to Realflo without getting errors. Is that still the case? This block is perfect for an application I'm building where I don't need to create a scanner every time. I still want my Realflo to be functional if I poll every scan or once every second or something.

Thanks.

[Joel_Weder · Accepted solution]

There's actually a newer version now, version 6. And yes it's certainly possible to poll regularly.