# A-TEE-SS-34

![Product image](https://novapart.co/image/farnell:4287908/)

**URL**: https://novapart.co/products/A-TEE-SS-3/4/a-tee-ss-34
**SKU**: A-TEE-SS-3/4
**Manufacturer**: DWYER
**Price**: €35.8600
**Stock**: 10+
**Lead Time**: 47 days (indicative)

## Specifications

| Parameter | Value |
|---|---|
| Svhc | No SVHC (04-Feb-2026) |

## Datasheet

📄 [Download PDF](https://novapart.co/datasheet/farnell:4287908/)

## **SERIES TDFS2** 

## THERMAL DISPERSION FLOW SWITCH Non-Mechanical, Low Pressure Drop, Large Pipe Sizes 

**==> picture [528 x 101] intentionally omitted <==**

**----- Start of picture text -----**<br>
CABLE CABLE<br>CABLE GLAND CABLE GLAND<br>1-1/8 1-1/8 5-5/8<br>HEX 4-3/16 STATUS INDICATOR HEX [142.88] STATUS INDICATOR<br>[106.17] SETPOINT TARGET SETPOINT TARGET<br>PROCESS<br>PROCESS<br>CONNECTION 1/2˝ NPT 2-25/32 CONNECTION<br>[70.49] 1/2˝ NPT OR BSPT<br>1-21/64 29/64 SENSOR<br>[33.78] [11.68] 1-29/32 SENSOR<br>[48.26]<br>TDFS2-1-P-06 TDFS2-2-P-06 TDFS2-1-P-06 TDFS2-2-P-06<br>VIDEOONLINE<br>**----- End of picture text -----**<br>


The **Series TDFS2 Thermal Dispersion Flow Switch** is a thermal flow switch that indicates whether the flow rate is above or below a user set flow rate. The unit incorporates two LED status indicators providing visual switch indication. The set flow rate (setpoint) is easily field adjustable with included magnet and the unit has both NO and NC NPN outputs. 

## **BENEFITS/FEATURES** 

- Better reliability and life expectancy than mechanical flow switches with no paddles or vanes to wear or break, no jams in the paddle movement, and no seals on movement assembly to wear or leak 

- Long operation life, as it is not affected by empty pipe by avoiding overheating with heating above the process temperature and then cooling down to process temperature 

- Lower system run cost due to low pressure drop with 10% insertion into the flow 

- (e.g. 1/8˝ for 3/4˝ schedule 40 pipe) 

## **APPLICATIONS** 

- Boiler flow proving 

- Hot water heaters 

- Chillers 

- Liquid transfer systems 

## **SPECIFICATIONS** 

**Service:** Compatible water-based fluids. **Wetted Materials:** 316 SS. 

**Switching Current:** 400 mA, derate 5 mA/°C above 23°C. 

**Pipe Range:** 1/2 to 1-1/2˝ (15 to 40 mm) or 2 to 10˝ (50 to 250 mm) (model selectable). 

**Current Consumption:** Average: 93 mA; Peak: 300 mA. 

**Electrical Connection:** 1/2˝ NPT female or cable gland with 4 conductor 22 AWG 6´ (1.83 m) long (model selectable). **Process Connection:** 1/2˝ NPT or BSPT male (model selectable). **Enclosure Rating:** NEMA 4X (IP65). **Housing Materials:** 316 SS, 416 SS, polycarbonate, neoprene, and acrylated urethane. 

**Setpoint Range:** 0.5 to 10 ft/s (0.15 to 3.0 m/s). 

- **Repeatability:** 0.07 ft/s (0.02 m/s) +3% of setpoint. 

- **Typical Deadband:** 0.1 ft/s (0.03 m/s) +15% of setpoint. 

**Temperature Limits:** Ambient: 5 to polycarbonate, neoprene, and acrylated 140°F (-15 to 60°C); Process: 5 to 140°F urethane. (-15 to 60°C), Storage: -40 to 185°F (-40 **Switch Type:** 1 NO NPN, 1 NC NPN. to 85°C). **Input Power and Protection:** 0.5A fuse **Pressure Limits:** 300 psig (20.67 bar). (resettable) reverse polarity protected. **Response Time:** Approximately 8 s. **Switched Output Protection:** 0.5A fuse **Power Requirement:** 9-24 VDC. (resettable) reverse polarity protected. **Compliance:** CE. 

## **MODEL CHART** 

|**MODEL CHART**|**MODEL CHART**|**MODEL CHART**|**MODEL CHART**|**MODEL CHART**|**MODEL CHART**|**MODEL CHART**|
|---|---|---|---|---|---|---|
|**Example**|**TDFS2 **|**-1 **|**-C **|**-06 **|**-BSPT **|**TDFS2-1-C-06-BSPT**|
|**Series**|TDFS2|||||Thermal dispersion flow switch|
|**Pipe Size**||1<br>2||||ersion flow switch<br>1/2 to 1-1/2˝ (15 to 40 mm)<br>2 to 10˝(50 to 250 mm)|
|**Electrical**<br>**Connection***|||C<br>B<br>P|||1/2˝ female NPT with PVC cable for conduit connection<br>Cable gland with burial rated cable<br>Cablegland with PVCjacketed cable|
|**Cable Length**||||X||Cable length(ft.)|
|**Options**|||||BSPT|1/2˝ BSPTprocess connection|
|*Per ft cable length adder.|||||||





## Links

- [View this product on Novapart](https://novapart.co/products/A-TEE-SS-3/4/a-tee-ss-34)
- [Request a quote for this part](https://novapart.co/quote/)
- [Supplier page](https://es.farnell.com/dwyer/a-tee-ss-3-4/a-tee-ss-34/dp/4287908)
---

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