Series-DS

Supported Applications

The Dwyer Series DS In-Line Flow Sensors are averaging pitot tubes designed for accurate and convenient flow rate sensing of compatible gases and liquids in Schedule 40 pipe. The series provides a complete flow-indicating system when paired with an appropriate differential pressure gage, such as the Capsuhelic® or Magnehelic®, delivering off-the-shelf solutions at an economical price point.

Documented media compatibility includes:

• Air
• Gases (including steam)
• Liquids (including water)

Operating Conditions & Performance

The Series DS sensors are rated for a maximum process temperature of 200°F (93.3°C) and a pressure rating of 200 psig (13.78 bar). The sensor tube is constructed from machined stainless steel, while the compression fitting utilizes brass.

Performance specifications vary by pipe size and media conditions:

• Air @ 60°F & 14.7 psia (D/P in. W.C.): Ranges from 0.05 to 186 depending on the specific model.
• Water @ 70°F (D/P in. W.C.): Ranges from 0.20 to 675 depending on the specific model.

The series offers excellent repeatability. Installation requires adherence to minimum straight pipe dimensions upstream and downstream of the sensor, which vary based on flow disturbances such as elbows, tees, valves, or reducers. For laboratory or high accuracy work, it is recommended to add 25% to the standard spacing values.

Configuration Options

The Series DS encompasses two distinct model families tailored for different pipe sizes and installation requirements:

• Series DS-300: Designed for insertion into pipelines via a compression fitting. Available for pipe sizes from 1" to 10" (Schedule 40). These sensors are furnished with instrument shut-off valves on both pressure connections, fitted with 1/8" female NPT connections.
• Series DS-400: Designed for larger insertion lengths up to 24 inches. Available for pipe sizes from 6" to 24" (Schedule 40 up to 20", Std. wt. for 24"). These models include a solid brass mounting adaptor with a 3/4" dia. compression fitting and a 3/4" male NPT thread.

Configuration options across the series include:

• Housing & Connections: DS-300 models feature a 1/4" male NPT compression fitting; DS-400 models utilize a 3/4" male NPT compression fitting.
• Valve Options: The -LV suffix indicates the sensor is supplied less valves, available at reduced cost where shut-off capability is not required.
• Accessories: Adapters with 1/4" SAE 45° flared ends are compatible with hoses from the Model A-471 Portable Capsuhelic® kit. The DS-400 series includes a pair of these adapters as standard equipment.
• Replacement Parts: Brass bushing (Model A-161, 1/4" x 3/8") is available for maintenance or installation needs.

Key Product Differences

The primary distinction between the two series lies in their physical dimensions and intended pipe size ranges. The Series DS-300 covers smaller diameters (1" to 10") with an overall length of approximately 1-15/16 inches for standard configurations, whereas the Series DS-400 addresses larger pipes (6" to 24") requiring insertion lengths up to 24 inches and a stem diameter of 3/4 inch.

Model numbering follows the format DS-Series-Pipe Size. For example, Model DS-300-1 is designated for 1" pipe size, while Model DS-400-6 covers 6" pipe sizes. Both series offer variants with and without valves (indicated by the -LV suffix), allowing selection based on specific process control requirements.