Troubleshooting and Applications Information

 

This section contains a mix of troubleshooting information and applications information. Troubleshooting information can help explain unexpected operation while applications information is meant to give insight into how to best use the application.

 

The problem is that when manual override is enabled the register that is used to control the sales valve is constantly changing when the value should be stable. This usually occurs when multiple control loops are enabled and share a single set of Input/Output Modbus Register Settings. Each enabled control loop should reference its own register settings. Registers settings cannot be shared across enabled control loops.

 

Additionally, when multiple control loops are enabled, each set of Input/Output Modbus Register Settings that is referenced by a control loop must be configured to use unique registers. By default, all Input/Output Modbus Register Settings instances have the same values.

 

When a control loop is not enabled, any Input/Output Modbus Register Settings group can be referenced. If an instance of the Input/Output Modbus Register Settings is not referenced by any control group then the register values don't matter and the registers won't be used.

 

User defined conditions are meant to allow user programs, such as ladder logic programs, to be integrated with a plunger control loop. That way, the user can create whatever custom logic he likes and then be able to trigger a flow condition or shut in condition.

 

Each user defined condition, for both flow and shut in, has an enable and delay that appear in the control parameters. Each user defined control parameter also has a configurable coil that is used to actually set the condition.

 

Enabled and disabling a condition is not enough to trigger the condition. A user defined condition must be enabled and then triggered for the condition to be accepted.

 

Also, it's important to understand that the sales valve is opened, and flow occurs, when all enabled flow conditions are met. This is a logical 'AND'. The sales valve is closed, and the well is shut in when any single enabled shut in condition is met. This is a logical 'OR'. In other words the behavior is different for flow and shut in conditions, and must be accounted for when using user defined conditions.