PUMP_FLOW_CALC¶
Function Block PUMP_FLOW_CALC
| Available as of PLC runtime system | V1.3 and above |
| Included in library | PUMP_AC500_V23.lib |
| Type | Function Block without historical values. |
The flow Calculation Function provides a reasonably accurate (typically ±3…6%) calculation of the flow without the installation of a separate flow meter. The flow is calculated on the basis of pump characteristics.
Note
This Function Block must be called cyclically with the cycle time of 50ms in the task configuration.
The user can define a PQ (power/flow) performance curve of the pump for the Flow Calculation function. The P (power input) and Q (flow rate) coordinates of five points on the curve are entered. The values are provided by the pump manufacturer. All points defined should lie within the practical operating range of the pump. The points are taken at max operation speed (as entered in the PUMP_INTERFACE block for this pump ® the value comes via the connected STATION structure), and scaled down by the block according to the actual speed. By this a good accuracy is achieved with limited parameterization effort.
Note
- The Flow Calculation function is not to be used for invoicing purposes,
- The Flow Calculation function cannot be used outside the normal operating range of the pump given by the pump curves.