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YOKOGAWA DN100DY100-EAL SR4-2D/SY
Product Overview:
The DY100 is a vortex shedding flowmeter manufactured by Yokogawa Electric Corporation, designed for precise volumetric and mass flow measurement of steam, liquids, and gases in industrial process environments. The DN100 designation indicates a 100 mm (4-inch) nominal bore diameter. The -EAL suffix denotes an Ex ia IIC T4 Ga explosion-proof (intrinsically safe) construction suitable for Zone 0 / Zone 1 hazardous areas. The SR4-2D/SY refers to the transmitter configuration with 4–20 mA DC output and pulse output, configured for 2-wire system power supply.
Detailed content
Technical Specifications:
| Parameter | Value |
|---|---|
| Nominal Bore Diameter | DN100 (100 mm / 4 inch) |
| Flow Range (Water) | 40 – 400 m³/h |
| Flow Range (Steam) | 250 – 2500 kg/h |
| Operating Pressure | Up to 4.0 MPa (40 bar) |
| Operating Temperature | -40°C to +250°C (standard); up to +350°C (high-temp version) |
| Accuracy (Liquid) | ±1.0% of reading (Re ≥ 20,000) |
| Accuracy (Gas/Steam) | ±1.5% of reading (Re ≥ 20,000) |
| Output Signal | 4–20 mA DC (2-wire), Pulse Output (open collector, max 1 kHz) |
| Power Supply | 12–45 VDC (2-wire loop powered) |
| Protection Class | IP67 (transmitter housing) |
| Explosion Proof | Ex ia IIC T4 Ga (EAL marking) |
| Wetted Material | SUS316L Stainless Steel |
| Process Connection | Wafer type (ANSI 150 RF flange, JIS 10K flange compatible) |
Functional Features:
- Piezoelectric sensor detects vortex shedding frequency generated by a triangular bluff body (shedder bar)
- Built-in temperature and pressure compensation for steam mass flow calculation
- Dual-output configuration: analog 4–20 mA + frequency pulse output
- Low flow cut-off function to eliminate measurement below minimum detectable flow
- Self-diagnostic capability with alarm output for sensor fault detection
Working Principle:
A bluff body (shedder bar) is placed perpendicularly in the flow stream. As fluid passes the bluff body, alternating vortices (Kármán vortex street) are shed downstream. The vortex shedding frequency (f) is directly proportional to the fluid velocity (v), governed by the equation: f = St × v / d, where St is the Strouhal number (~0.17 for triangular bluff body) and d is the bluff body width. The piezoelectric stress sensor mounted behind the bluff body converts the mechanical stress from vortex-induced vibration into an electrical signal. The transmitter processes this signal to calculate volumetric flow rate, mass flow rate (with T/P compensation), and totalized flow.
Advantages:
- No moving parts — ensures long-term reliability and minimal maintenance
- Wide turndown ratio (up to 50:1)
- Intrinsically safe design for hazardous area installations
- High accuracy across steam, liquid, and gas applications
Applicable Industries:
- Oil & Gas — steam metering, natural gas flow measurement
- Chemical & Petrochemical — process liquid and gas flow
- Power Generation — boiler steam flow, cooling water flow
- Pharmaceutical & Food — clean steam and purified water metering
Installation Requirements:
- Upstream straight pipe: minimum 15D (1500 mm for DN100)
- Downstream straight pipe: minimum 5D (500 mm for DN100)
- No valves, elbows, or reducers within the required straight pipe lengths
- Mount vertically or horizontally; for steam, mount with sensor facing upward to prevent condensate accumulation
- Ground the transmitter housing in hazardous area installations per IEC 60079-14
Usage Precautions:
- Do not exceed maximum rated pressure (4.0 MPa)
- Verify process media compatibility with SUS316L wetted parts
- Perform zero-point calibration after installation before commissioning
- Avoid installation in pipes with severe vibration — use vibration-dampening supports if necessary
