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ST-587 Series Inline PTSA & Turbidity Sensors
- Product Details
- Specifications
- Cooling Towers & Process Water
ST-587 Series Inline PTSA & Turbidity Sensors
The Pyxis ST-587 Series measures two things at once in the water line: PTSA, the fluorescent tracer used in many cooling and process water treatment programmes, and turbidity. A UV LED measures the tracer and a warm white LED measures turbidity, so one sensor reports both the treatment level and the clarity of the water.
Extra optical channels measure the colour and turbidity of the sample and correct the PTSA reading for them, in water up to 150 NTU. Two 4–20 mA outputs and RS-485 Modbus connect the sensor to any controller, PLC or DCS, and with the MA-CR Bluetooth adapter it can be checked and calibrated from the uPyxis app.
Two Models
- ST-587: UPVC body fitted in the ST-001 inline tee, up to 6.9 bar (100 psi)
- ST-587SS: 304 stainless steel body with ¾” FNPT ports, up to 20 bar (290 psi)
Short, Easy-to-Clean Optical Channel
Many inline fluorometers have a flat sensing face or a long, narrow flow cell that fouls and is hard to clean. The ST-587 has a short fluidic channel that cleans quickly, and the uPyxis app checks it for fouling before calibration. Its gallium phosphide photodiode and temperature- and humidity-tolerant optical filters keep readings steady over long periods without climate control.
ST-587 Series Specifications
| Item | ST-587 | ST-587SS |
|---|---|---|
| Part Number | 50906 | 58925 |
| Measures | PTSA (pyrenetetrasulfonic acid, CAS 59572-10-0) and turbidity | |
| PTSA Range | 0 – 500 ppb | |
| PTSA Resolution | 0.01 ppb | |
| PTSA Accuracy | ±1% of reading | |
| Turbidity Range | 0 – 200 NTU | |
| Turbidity Resolution | 0.1 NTU | |
| Turbidity Accuracy | ±2% of reading | |
| PTSA Excitation / Emission | 365 nm / 410 nm | |
| Turbidity Light Source | Warm white LED, 90° scatter (EPA 180.1 method) | |
| Interference Compensation | Automatic colour and turbidity compensation, up to 150 NTU | |
| PTSA Calibration | Single-point or two-point against a PTSA standard | |
| Turbidity Calibration | Single-point or two-point against a turbidity standard | |
| 4–20 mA Output Scale | PTSA 0 – 500 ppb; turbidity 0 – 200 NTU (20 mA point can be set lower in the uPyxis app) | |
| Outputs | Two 4–20 mA (PTSA and turbidity) and RS-485 Modbus, 8-pin connector | |
| Wireless Access | Bluetooth with MA-CR adapter or PowerPACK, uPyxis mobile and desktop app | |
| Power Supply | 22 – 26 V DC, about 2 W maximum at 20 mA | |
| Installation | ST-001 inline tee, ¾" FNPT socket and thread (supplied) | ¾" FNPT ports in the sensor body |
| Maximum Flow | 30 L/min (8 US gpm) through the ST-001 tee | – |
| Body Material | UPVC | 304 stainless steel |
| Maximum Pressure | 6.9 bar (100 psi) | 20 bar (290 psi) |
| Operating Temperature | 4 – 49 °C (40 – 120 °F) | |
| Storage Temperature | -7 °C to 60 °C (20 °F to 140 °F) | |
| Dimensions (L × Dia) | 172.7 × 36.6 mm (6.8 × 1.44 in) | 206.1 × 45.1 mm (8.1 × 1.66 in) |
| Weight | 170 g (0.37 lb) | 1,148 g (2.5 lb) |
| Cable | 1.5 m 8-pin bulkhead cable with adapter, plus 1.5 m 8-pin flying lead with adapter | |
| Enclosure Rating | IP67 | |
| Approvals | CE, RoHS, UKCA | |
Ideal for Cooling Towers & Process Water
The ST-587 Series is designed for cooling and process water, where the PTSA tracer shows the level of treatment and turbidity is a key measure of how well the programme is working. Both come from one installation point. The plastic ST-587 suits systems below 6.9 bar; the stainless steel ST-587SS suits higher-pressure systems up to 20 bar.
Key Features
- PTSA 0–500 ppb and turbidity 0–200 NTU in one sensor
- Accuracy ±1% of reading for PTSA, ±2% for turbidity
- Automatic colour and turbidity compensation, to 150 NTU
- Cleanliness check in place, before calibration
- Short fluidic channel, quick to clean
- Two 4–20 mA outputs (PTSA and turbidity) plus RS-485 Modbus
- Bluetooth calibration and diagnostics in the uPyxis app (with MA-CR adapter)
- Single-point calibration in place, or two-point in a beaker
- UPVC body to 6.9 bar, or stainless steel to 20 bar
- IP67; CE, RoHS and UKCA
