General Overview

The FLOWMATE (M-III) series is a compact liquid flowmeter designed primarily for monitoring fuel consumption in combustion appliances, heaters, and other applications requiring small flow measurement. It features a built-in pulse generator for remote control and totalizing counters to monitor throughput. The series includes meter sizes 38, 39, 40, 41, and 45, with size 38 specifically designed for water and pure water applications.

Specifications

Meter Sizes and Nominal Sizes

• Size 38: R 1/4 Rc1/4 (with fitting)
• Size 39: Rp 1/8 (6mm)
• Sizes 40, 41: Rp 1/8 (6mm)
• Size 45: Rp 1/4 (8mm)

Accuracy and Flow Ranges

• Size 38: 0.09–3 L/h with ±1% RD accuracy
• Size 39: 0.12–6 L/h with ±3% RD accuracy
• Sizes 40, 41, 45: Higher flow ranges up to 500 L/h with ±3% RD accuracy

Operating Conditions

• Temperature range: -10 to +60°C (size 38), -20 to +80°C (others)
• Maximum operating pressure: 0.3 MPa (size 38), 0.49 MPa (size 39), 0.98 MPa (sizes 40, 41, 45)

Materials

• Body materials: Stainless steel (SUS316), Aluminum with alumite treatment, Cast iron (FC200), or SCS14A stainless steel
• Rotor materials: PEEK resin (size 38), PPS resin (size 39), special resin, or stainless steel (sizes 40, 41, 45)
• Note: Aluminum body (code "L") is not suitable for water or corrosive liquids

Viscosity Compatibility

• Compatible with liquids ranging from 0.3 mPa·s up to 1000 mPa·s depending on meter size and rotor material

Features

• Compact design with integrated pulse generator
• Simple, robust, and cost-effective construction
• Remote totalizing counter for throughput monitoring and control
• Supports multiple flow control systems combined with pumps and valves
• Suitable for fuel cell applications and low to micro flow measurement

Pulse Output and Electrical Specifications

• Detection method: Magnetic sensor (MR sensor standard), optional reed switch (except sizes 38 and 39)
• Response frequency: Up to 1000 Hz
• Output pulse voltage: Minimum 0.5 VDC at 6.4–7.4 V supply, or minimum 2 VDC at 12–24 V supply
• Transmission distance: Up to 1 km with appropriate cable
• Power supply: 12–24 VDC ±10%
• Power consumption: Max 10 mA (0.3 W)
• Output pulse types: Scaled and unscaled pulses available depending on model

Pulse Unit and Meter Factors

• Meter sizes 40, 41, 45 have defined meter factors and pulse units, e.g., size 45 has 5.0 mL/pulse with max flow 500 L/h
• Sizes 38 and 39 provide unscaled pulses with lower flow rates

Meter Error and Pressure Drop

Graphs indicate meter error and pressure drop for different fuels (gasoline, kerosene, fuel oil) across flow rate percentages. Errors range from +1.0% to -1.0%, and pressure drops vary with flow rate and fluid viscosity.

Compliance and Standards

• Complies with EU Electro-Magnetic Compatibility Directive 89/336/EEC and related amendments
• Meets EN55011:1998/A1:1999 Group 1 Class B and EN61000-6-2:1999 standards

Product Codes and Options

• Models available: 38, 39, 40, 41, 45
• Body and rotor material combinations vary by model
• Connection options: With or without connector
• Pulse generation: MR sensor standard, reed switch optional (except sizes 38 and 39)
• Pulse types: Scaled pulse (MR sensor only), unscaled pulse

Combination with Receiving Instruments

The flowmeters can be connected to various receiving instruments such as totalizers (EL0122), F/I converters (SU1312), analog signal converters (4–20 mA DC or 1–5 V DC), and power units (SU1303) supporting multiple units. Pulse outputs are open-collector type and compatible with CPU outputs.

Strainers

• Strainers are recommended for meter sizes 38 and 39 (if fittings are not provided)
• Strainer materials: FC200 cast iron or SCS14A stainless steel body with SUS316 stainless steel net
• Maximum operating pressure for strainers: 1.57 MPa
• Strainer mesh size: #300 for size 38, #200 for others

Outline Dimensions

• Detailed dimensions provided for meter sizes 38, 39, 40, 41, and 45 including screw sizes and depths
• Typical dimensions: Size 38 approx. 84 mm length, sizes 40 and 41 approx. 43.8 mm width

Important Notes and Limitations

• Meter size 38 must be installed with physical orientation from bottom to top only
• Body material with code "L" (aluminum + alumite) is not suitable for water or corrosive liquids
• For measurement of materials other than water, purified water, and oils, consult the factory especially for resin rotor materials
• Provision of a lightning arrestor is recommended for pulse generator protection