WFK2 is a Karman vortex flow rate sensor that measures the flow of pure water and industrial water. Five flow rate ranges are available: 0.4 to 5, 1.6 to 20, 4 to 50, 8 to 100 and 20 to 250 L/min. A 2-screen color liquid crystal display shows the instantaneous flow rate and water temperature. It has switch output and analog output, and IO-Link compatible types can also be selected.
| Applicable Fluids | Pure water, industrial water |
| Flow Rate Range | WFK2-005: 0.4 to 5, WFK2-020: 1.6 to 20, WFK2-050: 4 to 50, WFK2-100: 8 to 100, WFK2-250: 20 to 250 L/min |
| Port Size | WFK2-005, 020, 050: 3/8, 1/2, 3/4 (Rc, G, NPT); WFK2-100, 250: 1, 1 1/4, 1 1/2 (Rc, G, NPT) |
| Port Material | Stainless steel (SUS304) |
| Max. Working Pressure | 1.0 MPa |
| Proof Pressure | 1.5 MPa |
| Manual Valve Internal Leakage | WFK2-005, 020, 050: 0 mL/min (with manual valve); WFK2-100, 250: no manual valve settings |
| Manual Valve Allowable Back Pressure | WFK2-005, 020, 050: 0.3 MPa; WFK2-100, 250: no manual valve settings |
| Ambient Temperature | 0 to 50 °C (85% RH or less, no condensation) |
| Fluid Temperature | 1 to 95 °C |
| Accuracy / Repeatability | Analog accuracy ±2.5% F.S., display accuracy ±2.5% F.S. ±1 digit (min. display unit) |
| Temperature Characteristics | ±5% F.S. (base temperature 25 °C, 10 to 50 °C) |
| Low Flow Cut | 5% of F.S. |
| Integrating Flow Range | 99,999 L or 99,999 m³ (unit selectable), reset when the power is turned off |
| Integrated Pulse Unit (L/pulse) | WFK2-005: 0.1 / 0.5 / 1; WFK2-020: 0.1 / 0.5 / 1 / 10; WFK2-050: 0.5 / 1 / 10 / 50; WFK2-100: 1 / 10 / 50 / 100; WFK2-250: 10 / 50 / 100 |
| Pressure Loss (at F.S.) | WFK2-005: 0.07 MPa (≈11 psi, 1 bar); WFK2-020, 050, 100: 0.05 MPa (≈8 psi, 1 bar); WFK2-250: 0.03 MPa (≈5 psi, 1 bar) |
| Response Time | 0.25 / 0.5 / 1 / 5 / 10 sec (default 1) |
| Measurement Temperature Range | 0 to 100 °C |
| Temperature Accuracy | Less than 50 °C: analog accuracy ±2 °C, display accuracy ±2 °C ±1 digit; 50 to 100 °C: analog accuracy ±3 °C, display accuracy ±3 °C ±1 digit |
| Display | 2-screen LCD: instantaneous flow rate 3 digits, water temperature 2 digits, integrating flow 5 digits, screen rotation |
| Analog Output | Standard: 0 to 5 VDC / 1 to 5 VDC; option: 4 to 20 mADC, 0 to 10 VDC / 1 to 10 VDC |
| Switch Output | NPN or PNP transistor open collector (can be switched from settings); max. load current 50 mA; max. applied voltage 30 VDC; internal voltage drop 2.0 V or less |
| Power Supply Voltage | Analog output standard: 12 to 24 VDC ±10%; analog output option: 24 VDC ±10% |
| Current Consumption | 50 mA or less |
| Mounting Orientation | Unrestricted in vertical/horizontal direction |
| Straight Piping Section | WFK2-005, 020, 050: none; WFK2-100, 250: IN side 10 D, OUT side 5 D |
| Degree of Protection | IP65 or equivalent |
| Weight | 3/8 (Rc, G, NPT): approx. 320 g; 1/2: approx. 320 g; 3/4: approx. 400 g; 1: approx. 870 g; 1 1/4: approx. 1,010 g; 1 1/2: approx. 1,100 g |
| Order Options | IO-Link/analog output: A switch/analog 0 to 5 VDC/1 to 5 VDC, B 4 to 20 mA DC, C 0 to 10 VDC/1 to 10 VDC, D to F IO-Link compatible; manual valve (cock) available only for flow rate ranges 005, 020, 050; standard cable or double-ended connector cable, bracket selectable |