# Universal Flow Skid

Reads from either a modbus flowmeter or an analog flowmeter.

## Hardware Used

-   PLC: Micro820 (2080-LC20-20QBB)
-   Slot 1: 2080-IF2

## Inputs

### Digital Inputs

| Input | Usage                        |
| ----- | ---------------------------- |
| 0     | Flowmeter Type (On = Modbus) |



### Analog Inputs

| Input 	| Usage		    	|
|---------  | -----------------	|
| 0			| 4-20mA Flowmeter	|
| 1			| 4-20mA Pressure	|

## Outputs

### Digital Outputs

| Output | Usage                   |
| ------ | ----------------------- |
| 0      | Analog Flowmeter in use |
| 1      | Modbus Flowmeter in use |

## Configuration

The system can be configured to use either an Analog Flowmeter or a Modbus Flowmeter. The system defaults to the Analog Flowmeter.

### To enable the modbus flowmeter do one of the following:

-   Jumper 24VDC to Digital Input 0
-   Write 1/True to the tag "sw_UseModbusFlowmeter" from SCADA

### To enable the analog flowmeter do BOTH of the following:

-   Remove the 24VDC jumper from Digital Input 0
-   Write 0/False to the tag "sw_UseModbusFlowmeter" from SCADA

When the system is configured to use the Analog Flowmeter, Digital Output 0 will be ON.

When the system is configured to use the Modbus Flowmeter, Digital Output 1 will be ON.

### Customizing Modbus Parameters

The system defaults for modbus parameters enable communication with the Promag Modbus meters. The following tags can be modified to enable communication with different device types:

| Tag                           | Default | Usage                           |
| ----------------------------- | ------- | ------------------------------- |
| cfg\_Flowmeter_ModbusNode     | 1       | Node Address of Flowmeter       |
| cfg\_FlowRate\_Register       | 201     | Register of Flow Rate           |
| cfg\_FlowTotalizerA\_Register | 203     | Register of Net Flow Total      |
| cfg\_FlowTotalizerB\_Register | 205     | Register of Positive Flow Total |
| cfg\_FlowTotalizerC\_Register | 207     | Register of Negative Flow Rate  |
| cfg\_ResetTotalizerA\_Coil    | 104     | Coil to Reset Totalizer A       |
| cfg\_ResetTotalizerB\_Coil    | 105     | Coil to Reset Totalizer B       |
| cfg\_ResetTotalizerC\_Coil    | 106     | Coil to Reset Totalizer C       |
| cfg\_Status\_Register         | 1       | Register of Device Status       |
| cfg\_Units\_Register          | 61      | First Units Register            |

The serial port is configured as a Master for Modbus RTU over RS485 with baud rate of 9600, 8N2.

## SCADA Tags

The following tags would be relevant to read over SCADA:

| Tag                        | Type   | Description                      | Access |
| -------------------------- | ------ | -------------------------------- | ------ |
| cmd\_ResetTotalizerA       | BOOL   | Reset Totalizer A                | RW     |
| cmd\_ResetTotalizerB       | BOOL   | Reset Totalizer B                | RW     |
| cmd\_ResetTotalizerC       | BOOL   | Reset Totalizer C                | RW     |
| Flow\_EU\_Max              | REAL   | EU Max Flow Scaling              | RW     |
| Flow\_EU\_Min              | REAL   | EU Min Flow Scaling              | RW     |
| Pressure\_EU\_Max          | REAL   | EU Max Pressure Scaling          | RW     |
| Pressure\_EU\_Min          | REAL   | EU Min Pressure Scaling          | RW     |
| cmd\_ClearFlowTotal        | BOOL   | Clear analog Flow Total Command  | RW     |
| sw\_UseModbusFlowmeter     | BOOL   | Use the modbus flowmeter         | RW     |
| use\_ModbusFlowmeter       | BOOL   | Status of using Modbus Flowmeter | R      |
| sts\_FlowMeterModbusOK     | BOOL   | Flowmeter Modbus OK Status       | R      |
| val\_Pressure              | REAL   | Pressure Reading                 | R      |
| val\_AI00\_uA              | REAL   | uA Reading on AI00               | R      |
| val\_AI01\_uA              | REAL   | uA Reading on AI01               | R      |
| val\_FlowRate              | REAL   | Flow Rate                        | R      |
| val\_FlowTotalizerA        | REAL   | Flow Totalizer A (Net Flow)      | R      |
| val\_FlowTotalizerB        | REAL   | Flow Totalizer B (Fwd Flow)      | R      |
| val\_FlowTotalizerC        | REAL   | Flow Totalizer C (Rev Flow)      | R      |
| val\_FlowRate\_Units       | STRING | Flow Rate Units                  | R      |
| val\_FlowTotalizerA\_Units | STRING | Flow Totalizer A Units           | R      |
| val\_FlowTotalizerB\_Units | STRING | Flow Totalizer B Units           | R      |
| val\_FlowTotalizerC\_Units | STRING | Flow Totalizer C Units           | R      |
| val\_StatusString          | STRING | FlowMeter Status                 | R      |

## Contributors

-   [Patrick McDonagh](https://github.com/patrickjmcd) - Owner
-   Ben Nabors - Collaborator