1. Product Overview
The Dwyer Rate-Master Series RM Flowmeter is a direct reading precision flowmeter designed for general use. This model, the RMB-83-BV, features a 5-inch scale and measures flow rates from 1 to 20 GPH (Gallons Per Hour) for water, equipped with a brass valve for flow adjustment. Its robust construction and clear scale provide reliable and accurate flow measurement in various applications.
Image 1.1: Front view of the Dwyer Rate-Master Series RM Flowmeter, highlighting its transparent body, measurement scale, and control valve.
2. Features
- Service: Compatible with various gases and liquids.
- Wetted Materials: Body constructed from Polycarbonate; O-rings made of Neoprene & Buna-N; Metal parts are Stainless steel (except for the optional brass valve); Float material varies (Stainless steel, black glass, aluminum, K monel, tungsten carbide) depending on the specific flow range.
- Temperature Limit: Operates safely up to 130°F (54°C).
- Pressure Limit: Designed to withstand pressures up to 100 psi (6.9 bar).
3. Safety Information
Read and understand all instructions before installing or operating the flowmeter. Failure to follow these instructions may result in product damage, property damage, or personal injury.
- Ensure the flowmeter is used only with compatible gases and liquids as specified in the "Wetted Materials" section. Incompatible fluids can damage the device and lead to leaks.
- Do not exceed the maximum temperature limit of 130°F (54°C) or the maximum pressure limit of 100 psi (6.9 bar). Operating beyond these limits can cause failure and potential hazards.
- Install the flowmeter in a location where it is protected from physical damage and extreme environmental conditions.
- Always depressurize and drain the system before attempting any installation, maintenance, or removal of the flowmeter.
- Use appropriate personal protective equipment (PPE) when handling fluids or working with pressurized systems.
4. Setup and Installation
Proper installation is crucial for accurate readings and safe operation.
- Mounting: The flowmeter should be mounted vertically with the inlet at the bottom and the outlet at the top. Ensure it is securely fastened to a rigid surface using appropriate mounting hardware (not included).
- Piping: Connect the flowmeter into the process line using suitable fittings. Ensure all connections are leak-tight. Avoid applying excessive torque to the flowmeter connections, as this can damage the polycarbonate body.
- Straight Pipe Runs: For optimal accuracy, it is recommended to have straight pipe runs of at least 5 pipe diameters upstream and 3 pipe diameters downstream of the flowmeter.
- System Purge: Before introducing the process fluid, slowly purge the system to remove any air or debris that could affect readings or damage the float.
- Initial Check: After installation, slowly introduce the process fluid and check for any leaks at the connections.
5. Operation
The Rate-Master Series RM Flowmeter provides a direct visual indication of flow rate.
- Reading the Flow Rate: The flow rate is indicated by the position of the float within the tapered tube. Read the flow rate at the center of the float, aligning it with the corresponding mark on the scale. The scale is calibrated in GPH (Gallons Per Hour) for water.
- Adjusting Flow (Brass Valve Model): This model is equipped with a brass valve at the bottom. To adjust the flow rate, slowly turn the black knurled knob. Turning clockwise will decrease flow, and turning counter-clockwise will increase flow. Make small adjustments and observe the float's position until the desired flow rate is achieved.
- Operating Conditions: Ensure the fluid is within the specified temperature and pressure limits for accurate and safe operation.
6. Maintenance
The Dwyer Rate-Master Flowmeter is designed for minimal maintenance. Regular inspection is recommended to ensure continued accuracy and performance.
- Cleaning: If the flowmeter becomes dirty or fouled, it may be disassembled for cleaning. Refer to the "Wetted Materials" section to ensure cleaning agents are compatible with polycarbonate, neoprene, Buna-N, and stainless steel. Use mild soap and water; avoid abrasive cleaners or solvents.
- Inspection: Periodically inspect the flowmeter for signs of wear, cracks in the polycarbonate body, or leaks at the connections. Check the float for any obstructions or damage.
- O-Ring Replacement: If leaks occur around the O-rings, they may need to be replaced. Use genuine Dwyer replacement parts to ensure compatibility and proper sealing.
- Storage: If storing the flowmeter for an extended period, ensure it is clean, dry, and stored in a protected environment away from direct sunlight and extreme temperatures.
7. Troubleshooting
| Problem | Possible Cause | Solution |
|---|---|---|
| No flow indication / Float at bottom | No flow in line; Valve closed; Obstruction in line or flowmeter. | Verify system flow; Open valve; Check for and remove obstructions. |
| Inaccurate reading | Flowmeter not mounted vertically; Fluid properties differ from calibration; Debris on float or tube; Pulsating flow. | Ensure vertical mounting; Confirm fluid matches water (for GPH water scale); Clean flowmeter; Install pulsation dampener if necessary. |
| Leaks at connections | Loose fittings; Damaged O-rings; Cracked body. | Tighten fittings (do not overtighten); Replace O-rings; Replace flowmeter if body is cracked. |
| Float sticking | Debris in tube; Static electricity build-up. | Clean flowmeter; Ensure proper grounding if static is an issue. |
8. Specifications
| Model Number | RMB-83-BV |
| Flow Range | 1-20 GPH Water |
| Scale Length | 5 inches |
| Service | Compatible gases and liquids |
| Wetted Materials | Body: Polycarbonate; O-ring: Neoprene & Buna-N; Metal Parts: Stainless steel (except for optional brass valve); Float: Stainless steel, black glass, aluminum, K monel, tungsten carbide (depending on range) |
| Temperature Limit | 130°F (54°C) |
| Pressure Limit | 100 psi (6.9 bar) |
| Package Dimensions | 8.8 x 2.8 x 1.5 inches |
| Item Weight | 14.4 ounces |
| Manufacturer | Dwyer Instruments |
9. Warranty and Support
For specific warranty information and technical support, please refer to the official Dwyer Instruments website or contact their customer service department. Keep your purchase receipt as proof of purchase for warranty claims.
Manufacturer: Dwyer Instruments
Website: www.dwyer-inst.com (Example link, actual link may vary)
