The KOFLOC Model 3810DS Series Digital Mass Flow Meter with Integrated Display (Detailed Configuration: 3810 DS-B-D/4M-OP-100L-N2 / Analog output) is 100% engineered, assembled, and calibrated in Japan by KOFLOC Corp. (Kojima Instruments Inc.) – an internationally recognized technological benchmark with more than 75 years of specialized innovation in micro-flow fluidics and analytical measurement instrumentation. Classified as KOFLOC’s premier cost-effective Mass Flow Meter with built-in indicator, the Model 3810DS eliminates the need for external secondary display modules and separate power supplies, providing an autonomous, highly reliable, and visually accessible flow monitoring solution right at the equipment site.

At the technological core of the KOFLOC Model 3810DS is its field-proven capillary bypass thermal mass flow sensing element. By directly detecting the heat transfer between traveling gas molecules and the capillary sensor tube, the meter evaluates genuine mass flow unaffected by supply pressure fluctuations or ambient temperature shifts. Engineered without internal moving parts (No moving parts), the instrument completely eliminates mechanical wear, particle generation, and pressure head drops. The built-in digital display front panel provides simultaneous visualization of both momentary instantaneous flow rate and accumulated totalized volume, accompanied by dual LED alarm indicators for high/low threshold limit monitoring.

This specific unit is factory calibrated for Nitrogen gas (N2) across a large-capacity 100 L/min (100 SLM) measuring span referenced to standard conditions. Constructed with a robust nickel-plated brass body block, SUS316 internals, fluorocarbon seals, and an impact-resistant Grilamid TR55 display enclosure, the meter operates under pressures up to 0.5 MPa (G) with a 1.0 MPa proof pressure threshold. Most importantly, the Model 3810DS operates on a standard single industrial 24 VDC supply (eliminating traditional ±15V dual supply constraints) and provides a linear analog output (1–5 VDC or 4–20 mA) alongside an NPN open-collector pulse output for seamless PLC, DCS, and plant SCADA integration. The KOFLOC 3810DS is an ideal flow measurement standard for industrial furnace blanketing, food MAP packaging, laser cutting auxiliary lines, and laboratory gas manifold systems worldwide.

• Manufacturer: KOFLOC Corp. (Kojima Instruments Inc.)
• Origin: 100% Japan (Kyoto, Japan)
• Product Series: Low-Cost Digital Thermal Mass Flow Meter with Built-in Display
• Complete Model Code: 3810 DS-B-D/4M-OP-100L-N2 (Analog output)
• Base Series: Model 3810DS Series (Model 3810DS / 3810DSII)
• Sensing Principle: Capillary bypass thermal mass flow sensor (no moving parts)
• Calibrated Process Fluid: Nitrogen gas (N2) [compatible with Air, O2, Ar, CO2...]
• Rated Full-Scale Flow Capacity: 100 L/min (100 SLM - Standard Liters per Minute)
• Integrated Digital Display: High-contrast digital readout showing instantaneous flow rate and totalized accumulated volume
• Measurement Accuracy: Within ±2.0% to ±3.0% F.S. (large flow rate range at 25 °C reference)
• Measurement Repeatability: Within ±0.5% F.S.
• Temperature Coefficient: ±0.20% F.S./°C (guaranteed within 15 °C to 35 °C)
• Operating Pressure Range: 0.0 to 0.5 MPa (G) (approx. 0 to 5 bar)
• Proof Pressure Resistance: 1.0 MPa (G) (approx. 10 bar / 145 psi)
• Analog Output Signal: 1 to 5 VDC linear voltage (load resistance ≥ 10 kΩ) or 4 to 20 mA current output (load resistance ≤ 250 Ω)
• Pulse Output (Totalized Flow): NPN open collector transistor output (Max rating: DC 30V 50mA, pulse width approx. 50ms)
• Alarm Functionality: Programmable dual-point threshold alarm (AL1, AL2) with status indicator LEDs
• Process Connection Fitting: 1/4" Male thread connector (/4M)
• Fluid Contact Materials (Wetted Parts):
  - Main Body Block: Nickel-plated Brass (Brass specification) or SUS
  - Sensor Tube & Internal Flow Elements: SUS316 / SUS304 / PTFE
  - Sealing O-rings: Fluoroelastomer FKM (Viton)
  - Display Enclosure: Engineering thermoplastic (Grilamid TR55)
• Operating Power Supply: 24 VDC (±5% or ±10%), approx. 60 to 100 mA current consumption
• Operating Ambient Temperature: 5 °C to 45 °C
• Operating Ambient Humidity: 10% to 85% RH (Non-condensing)
• Net Weight: Compact profile, approx. 350 g – 450 g
• Certifications: CE marked, RoHS compliant, factory pre-calibrated with traceable test inspection sheet
• Applicable Industries & Systems: Nitrogen blanketing and furnace atmosphere monitoring, tank inerting/purging systems, modified atmosphere packaging (MAP) in food and pharmaceuticals, assist gas flow metering for laser cutters, compressed air energy management, laboratory test chambers, and industrial automated gas distribution panels.