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Series-TDS
TDS Thermal Flow Switch for Non-Coating Liquids, Adjustable SPDT Output
Models In Stock
- Detects non-coating liquid flow via thermal dispersion, ideal for pump and process protection
- Adjustable SPDT switch point, selectable NO/NC output, with LED flow status indicator
- Rated for up to 150 psi (10 bar) and 32-140 °F (0-60 °C) with viscous fluids to 200 cP
- Wetted materials in PP/PPS or PVDF offer chemical compatibility for oils, solvents and water-based liquids
Series-TDS
From
$
542.55
Models In Stock
Product Overview
- Drift 0.5% of setpoint
- Electrical Connection Cable
- Media Compatibility Clean process / cooling water, Corrosive chemicals / acids / bases, Hydraulic fluids, Oils / lubricants, Organic solvents, Solvents, Water, Water-based fluids
- Mounting Orientation None
- Operating Temperature, Max 140 °F
- Operating Temperature, Min 32 °F
- Power Consumption 50 mA
- Pressure Limits Up to 150 psi
- Pressure Limits Note 150 psi (10 bar) @25°C, derated @ 1.667 psi (.113 bar)per °C above 25°C
- Measurement Pressure Type Gauge
- Process Connection Size 3/4 in
- Process Connection Type NPT Male
- Repeatability ± 5%
- Repeatability Note ± 5% of setpoint
- Response Time 1 to 10 s
- Series ID Series-TDS
- Supply Power Type DC
- Supply Voltage 12 to 36 Vdc
- Switch Indication LED for Flow Status
- Switch Rating 60 Vac/60 Vdc @ 1 A
- Switch Type SPDT NO/NC, Selectable
- Velocity, Max 3 ft/s
- Velocity, Min 0.04 ft/s
- Viscosity Range 1 to 200 cPs
- Weight 94 g
- Wire Gauge 22 AWG
Supported Applications
The Series TDS Thermal Dispersion Flow Switch by Dwyer is designed for reliable low or no-flow detection in relatively clean, non-coating liquids and gases. The series provides solid-state flow detection suitable for pump and process protection applications where the liquid temperature remains constant throughout the process.
- Liquid examples include water and acetic acid
- Corrosive liquids and gases (with PVDF or PP-Ryton® models)
- Pipe sizes from 3/4" to 1-1/2" using short sensors; pipe sizes from 2" to 16" using long sensors
DO NOT USE THE TDS SERIES GENERAL PURPOSE FLOW SWITCHES IN HAZARDOUS LOCATIONS. The sensing tip must always be submerged in the liquid and never exposed to air.
Operating Conditions & Performance
The Series TDS operates within a process temperature range of 32° to 140°F (0 to 60°C) and an ambient operating temperature of -40° to 140°F (-40° to 60°C). The measurement range covers 0.04 to 3 fps (0.012 to 0.91 m/s) for liquids and 1 to 90 fps for gases, with a repeatability of ±5% of set point at fixed temperature.
Pressure rating is 150 psi (10 bar) @ 25°C, derated at 1.667 psi (1.13 bar) per °C above 25°C. The response time ranges from 1 to 10 seconds. For best results in liquid applications, avoid installing where bubbles are present or where tips may be out of liquid.
Electrical and Signal Specifications
- Power Supply: 12-36 VDC (Manual specifies 14-36 VDC; data sheet specifies 12 to 36 VDC)
- Output Signal: SPDT relay output, selectable NO or NC via power supply wiring polarity
- Relay Rating: 1A (General: 120 VAC / 60 VDC @ 1A; CE rated applications: 60 VAC / 60 VDC @ 1A)
- Load Resistance: Max. Series Resistance of 1,400 Ohms (at 36 VDC) per manual
- Cable: Shielded cable; data sheet specifies 22 AWG 3-wire, 10 ft (3 m) length; manual notes 4-conductor #22 AWG shielded cable
Configuration Options
The series is configurable across sensor lengths and wetted materials to accommodate different pipe sizes and media compatibility requirements. The adjustable set point allows calibration for specific flow velocities.
Sensor Lengths and Mounting
- Short Sensor: 3.0" (76mm) overall length, suitable for ½" to 1-1/2" pipe sizes; insertion dimension B is 0.7" (19mm)
- Long Sensor: 4.5" (114mm) overall length, suitable for 2" and up pipe sizes; insertion dimension B is 2.1" (54mm)
Wetted Materials
- Polypropylene-Ryton®: Standard configuration for general liquids
- PVDF (Polyvinylidene Fluoride): Available for corrosive liquids and gases
Cable Materials
- Polypropylene cable with PP-Ryton® body models
- FEP cable with PVDF body models
Mounting orientation is flexible (any orientation), but the two temperature probes must always be perpendicular to the flow. Never over-tighten the sensor beyond 80 inch-pounds torque.
Key Product Differences
The Series TDS includes four primary model configurations distinguished by wetted material and insertion length:
- TDS112: Short (3.0"), PP-Ryton® body, Polypropylene cable
- TDS122: Long (4.5"), PP-Ryton® body, Polypropylene cable
- TDS212: Short (3.0"), PVDF body, FEP cable
- TDS222: Long (4.5"), PVDF body, FEP cable
The series features an LED for flow status and calibration indication. The switch point is factory calibrated at 0.2 fps with adjustable set points via the unit's configuration.
PDFs & Manuals
