Pyxis ST-601 User manual

ST-601 User Manual [email protected] | [phone]

ST-601 ClO2 Concentraon Sensor
User Manual
April 28, 2021
Rev. 2.01
Pyxis Lab, Inc.
1729 Majesc Dr. Suite 5
Lafayee, CO 80026 USA
www.pyxis-lab.com
© 2017 Pyxis Lab, Inc.
Pyxis Lab Proprietary and Condenal

Table of Contents
1 Introducon 2
1.1 Main Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
2 Specicaons 3
3 Unpacking Instrument 3
3.1 Standard Accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
3.2 Oponal Accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
4 Installaon 5
4.1 In-line Piping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
4.2 Teon Tubing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
4.3 Wiring ................................................. 6
4.4 Connecng via Bluetooth . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
4.5 Connecng via USB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
5 Setup and Calibraon with uPyxis® Mobile App 8
5.1 Download uPyxis® Mobile App . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
5.2 Connecng to uPyxis® Mobile App . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
5.3 Calibraon Screen and Reading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
5.4 Diagnosis Screen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
5.5 Device Info Screen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
6 Setup and Calibraon with uPyxis® Desktop App 12
6.1 Install uPyxis® Desktop App . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
6.2 Connecng to uPyxis® Desktop App . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
6.3 Informaon Screen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
6.4 Calibraon Screen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
6.5 Diagnosis Screen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
7 Outputs 15
7.1 4–20mA Output Setup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
7.2 Adjusng 4–20mA Span . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
7.3 Communicaon using Modbus RTU . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
8 Sensor Maintenance and Precauon 17
8.1 Methods to Cleaning the ST-601 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
8.2 Storage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
9 Troubleshoong 18
10 Contact Us 18

Warranty Informaon
Condenality
The informaon contained in this manual may be condenal and proprietary and is the property of Pyxis
Lab, Inc. Informaon disclosed herein shall not be used to manufacture, construct, or otherwise reproduce
the goods described. Informaon disclosed herein shall not be disclosed to others or made public in any
manner without the express wrien consent of Pyxis Lab, Inc.
Standard Limited Warranty
Pyxis Lab warrants its products for defects in materials and workmanship. Pyxis Lab will, at its opon, repair
or replace instrument components that prove to be defecve with new or remanufactured components
(i.e., equivalent to new). The warranty set forth is exclusive and no other warranty, whether wrien or oral,
is expressed or implied.
Warranty Term
The Pyxis warranty term is thirteen (13) months ex-works. In no event shall the standard limited warranty
coverage extend beyond thirteen (13) months from original shipment date.
Warranty Service
Damaged or dysfunconal instruments may be returned to Pyxis for repair or replacement. In some in-
stances, replacement instruments may be available for short duraon loan or lease.
Pyxis warrants that any labor services provided shall conform to the reasonable standards of technical com-
petency and performance eecve at the me of delivery. All service intervenons are to be reviewed and
authorized as correct and complete at the compleon of the service by a customer representave, or des-
ignate. Pyxis warrants these services for 30 days aer the authorizaon and will correct any qualifying
deciency in labor provided that the labor service deciency is exactly related to the originang event. No
other remedy, other than the provision of labor services, may be applicable.
Repair components (parts and materials), but not consumables, provided during a repair, or purchased
individually, are warranted for 90 days ex-works for materials and workmanship. In no event will the in-
corporaon of a warranted repair component into an instrument extend the whole instrument’s warranty
beyond its original term.
Warranty Shipping
A Repair Authorizaon (RA) Number must be obtained from Pyxis Technical Support before any product can
be returned to the factory. Pyxis will pay freight charges to ship replacement or repaired products to the
customer. The customer shall pay freight charges for returning products to Pyxis. Any product returned to
the factory without an RA number will be returned to the customer. To receive an RMA you can generate a
request on our website at hps://pyxis-lab.com/request-tech-support/.
Pyxis Technical Support
Contact Pyxis Technical Support at [phone], [email protected], or by lling out a request for
support at hps://pyxis-lab.com/request-tech-support/.
ST-601 User Manual [email protected] | [phone]

1 Introducon
The Pyxis ST-601 inline sensor is uniquely designed to measure the real-me mass/mass concentraon of
chlorine dioxide (ClO2). The ST-601 sensor measures the opcal absorbance of the ClO2 soluon using a
UV light source. The sensor has a built-in reference light source and a reference light detector in addion
to the main light source and main light detector.
The ST-601 oers an expanded range and a RTD temperature output signal. This features allow the user to
measure ClO2 as high as 0.35% (mass/mass) and obtain a temperature measurement, useful when required
to consider the impact of atmospheric temperature condions on variable ClO2 concentraon readings.
The ST-601 can be connected to any device that accepts an isolated or non-isolated 4–20mA input or RS-485
Modbus. As with all Pyxis inline sensors, the ST-601 sensor can be wirelessly accessed via Bluetooth when
used in conjuncon with the MA-WB Bluetooth Adapter or PowerPACK Series Auxiliary Box and the uPyxis®
App for mobile and desktop devices. Direcons on this wireless calibraon capability are included in this
manual.
Primary Installaon Format
The primary method is to install the probe in-line with the sucon side of the chemical feed pump in piping
format. This method should ideally run in a vercal line to avoid chlorine gas bubble interference. This can
be done with the standard ST-001 Inline Tee Assembly (3/4” FNPT) provided with each sensor. Pyxis also
oers 2” and 3” inline tee assemblies as an accessory opon if required.
Teon Tube Installaon Format
The second method is to install the probe in-line using the unique 1/4” OD (7 mm OD) clear Teon tubing
adapter 6 inches in length. This tubing can be passed “THROUGH” the opcal channel allowing to use the
sensor with smaller chemical feed line installaons on the sucon side of the chemical feed pump.
*NOTE*For enhanced ambient light interference prevenon, Pyxis recommends users to
apply black electrical tape or shrink wrap to allow sample darkening prior to and aer the
opcal channel as seen in Figure 3.
1.1 Main Features
The ST-601 sensor includes the following features:
• Can be conveniently connected to the sucon or discharge side of the bleach pump in both inline Tee
(ST-001) or 1/4” Teon tubing format with using a union; both included with sensor.
• Can be wirelessly calibrated using a known chlorine dioxide concentraon standard with the uPyxis®
Mobile or Desktop App via a MA-WB Bluetooth/WiFi adapter or PowerPACK Series Auxiliary Box.
• Diagnosc informaon (sensor tubing fouling and failure modes) can be communicated to digital
displays via Modbus RTU.
• Oers an expanded range and a temperature signal communicated via 2-channel 4–20mA outputs
and a RS-485 output, Modbus RTU.
• Easy to remove from the system for cleaning and calibraon without the need for any tools.
ST-601 User Manual [email protected] | [phone]

2 Specicaons
Table 1. ST-601 Specicaons
Specicaon*ST-601
Part Number (P/N) 50232
Chlorine Dioxide
Concentraon Range
0–0.35% mass/mass
(RTD Compensated)
Chlorine Dioxide
Concentraon
Resoluon
0.01%
Chlorine Dioxide
Concentraon Accuracy
±2% of reading or ±0.1%
Temperature Output
Range
4 mA: 32 °F (0 °C),
20 mA: 212 °F (100 °C)
Method UV Absorbance
Calibraon Two-point calibraon against known ClO2 concentraon soluon
Outputs 2x 4–20mA Analog Output,
RS-485 Digital Output with Modbus protocol
Installaon 1/4” OD (7 mm) Teon tubing for measurement ow and custom tee
assembly (P/N: ST-001) with 3/4” female socket & NPT threaded ports
Cable Length 5  with IP67 connectors & 2  ying lead with IP67 adapter
Power Supply 22–26 VDC, 2W
Dimension (L ×Dia) 6.8 ×1.44 inch (172.7 ×36.6 mm)
Weight 0.37 lbs (170 g)
Material CPVC
Operaonal
Temperature
40–120 °F (4–50 °C)
Storage Temperature 20–140 °F (-7–60 °C)
Pressure Up to 100 psi (0.7 MPa)
Enclosure Rang IP67
Regulaon CE/RoHS
*With Pyxis’s connuous improvement policy, these specicaons are subject to change without noce.
3 Unpacking Instrument
Remove the instrument and accessories from the shipping container and inspect each item for any damage
that may have occurred during shipping. Verify that all accessory items are included. If any item is missing
or damaged, please contact Pyxis Lab Customer Service at [email protected].
3.1 Standard Accessories
• Tee Assembly 3/4” NPT (1x Tee, O-ring, and Nut) P/N: ST-001
• 7-Pin Female Adapter/Flying Leads Cable (2 ) P/N: MA-1100
• Clear Teon Tubing 1/4” OD (6”) Adapter
• User Manual available online at hps://pyxis-lab.com/support/
ST-601 User Manual [email protected] | [phone]

3.2 Oponal Accessories
The following oponal accessories can be ordered at or[email protected] or the Pyxis E-Store at hps://pyxis-
lab.com/shop/
Figure 1.
ST-601 User Manual [email protected] | [phone]

4 Installaon
4.1 In-line Piping
The provided ST-001 Tee Assembly can be connected to a pipe system through the 3/4” female ports, ei-
ther socket or NPT threaded. The ST-001 Tee Assembly should be placed in-line with the sucon side of the
chemical feed pump. This method should ideally in a vercal line run to avoid chlorine gas bubble interfer-
ence. Pyxis also oers 2” and 3” inline tee assemblies as an accessory opon if required. To properly install
the ST-601 sensor into the ST-001 Tee Assembly, follow the steps below:
1. Insert the provided O-ring into the O-ring groove on the tee.
2. Insert the ST-601 sensor into the tee.
3. Tighten the tee nut onto the tee to form a water-ght, compression seal.
Figure 2. Dimension of the ST-601 sensor and the ST-001 Tee Assembly (mm)
ST-601 User Manual [email protected] | [phone]

4.2 Teon Tubing
The provided 1/4” OD (7 mm OD) clear Teon tubing adapter 6” in length. This tubing can be passed
“THROUGH” the opcal channel to allow for use of the sensor with smaller chemical feed line installaons
on the sucon side of the chemical feed pump. Users can use convenonal 1/4” OD compression ngs to
connect desired inlet and outlet bleach line size to the ST-601. This method should ideally in a vercal line
run to avoid chlorine gas bubble interference.
*NOTE*For enhanced ambient light interference prevenon, Pyxis recommends users ap-
ply black electrical tape or shrink wrap to allow sample darkening prior to and aer the
opcal channel as seen in Figure 3.
Figure 3. ST-601 sensor with clear Teon tube adapter
4.3 Wiring
If insucient waage is available from the connected controller (ie. 2.0 W), Pyxis recommends the Power-
PACK Series Auxiliary Power & Communicaon Box highlighted in the Oponal Accessories secon.
*NOTE*There is no 4–20mA negave wire to the controller, please connect controller 24V
power ground terminal to controller 4–20mA negave terminal with a short wire.
Follow the wiring table below to connect the ST-601 sensor to a controller:
Table 2.
Wire Color Designaon
Red 24V +
Black 24V Power ground
White 4–20mA + for Temperature
Green 4–20mA + for ClO2
Blue RS-485 A
Yellow RS-485 B
Clear Shield, earth ground
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4.4 Connecng via Bluetooth
A Bluetooth adapter (P/N: MA-WB) can be used to connect a ST-601 sensor to a smart phone with the
uPyxis® Mobile App or a computer with the uPyxis® Desktop App.
Figure 4. Bluetooth connecon to ST-601 sensor
4.5 Connecng via USB
A USB-RS485 adapter (P/N: MA-485) can be used to connect a ST-601 sensor to a computer with the uPyxis®
Desktop App.
*NOTE*Using non-Pyxis USB-RS485 adapters may result in permanent damage of the ST-
601 sensor communicaon hardware.
Figure 5. USB connecon to ST-601 sensor
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5 Setup and Calibraon with uPyxis® Mobile App
5.1 Download uPyxis® Mobile App
Download uPyxis® Mobile App from Apple App Store or Google Play.
Figure 6. uPyxis® Mobile App installaon
ST-601 User Manual [email protected] | [phone]

5.2 Connecng to uPyxis® Mobile App
Connect the ST-601 sensor to a mobile smart phone according to the following steps:
1. Open uPyxis® Mobile App.
2. On uPyxis® Mobile App, pull down to refresh the list of available Pyxis devices.
3. If the connecon is successful, the ST-601 and its Serial Number (SN) will be displayed (Figure 7).
4. Press on the ST-601 sensor image.
Figure 7.
ST-601 User Manual [email protected] | [phone]

5.3 Calibraon Screen and Reading
When connected, the uPyxis® Mobile App will default to the Calibraon screen. From the Calibraon
screen, you can perform calibraons by pressing on Zero Calibraon,Slope Calibraon, and 4–20mA Span.
Follow the screen instrucons for each calibraon step.
Figure 8.
ST-601 User Manual [email protected] | [phone]

5.4 Diagnosis Screen
From the Diagnosis screen, you can check the diagnosis condion. This feature may be used for technical
support when communicang with [email protected].
To preform a Cleanliness Check, rst select the Diagnosis Condion which denes the uid type that the
ST-601 sensor in currently measuring, then press Cleanliness Check. If the sensor is clean, a Clean mes-
sage will be shown. If the sensor is severely fouled, a Dirty message will be shown. In this case, follow the
procedure in the Methods to Cleaning the ST-601 Sensor secon of this manual.
Figure 9.
ST-601 User Manual [email protected] | [phone]

5.5 Device Info Screen
From the Device Info screen. You can name the Device or Product as well as set the Modbus address.
Figure 10.
6 Setup and Calibraon with uPyxis® Desktop App
6.1 Install uPyxis® Desktop App
Download the latest version of uPyxis® Desktop soware package from: hps://pyxis-lab.com/upyxis/ this
setup package will download and install the Microso.Net Framework 4.5 (if not previously installed on the
PC), the USB driver for the USB-Bluetooth adapter (MA-NEB), the USB-RS485 adapter (MA-485), and the
main uPyxis® Desktop applicaon. Double click the uPyxis.Setup.exe le to install.
Figure 11. uPyxis® Desktop App installaon
Click Install to start the installaon process. Follow the screen instrucons to complete the USB driver and
uPyxis® installaon.
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6.2 Connecng to uPyxis® Desktop App
Connect the ST-601 sensor to a Windows computer using either a Bluetooth/USB adapter (P/N: MA-NEB)
or a USB-RS485 adapter (P/N: MA-485) according to the following steps:
1. Plug the Bluetooth/USB adapter or USB-RS485 adapter into a USB port in the computer.
2. Launch uPyxis® Desktop App.
3. On uPyxis® Desktop App, click Device →Connect via USB-Bluetooth or Connect via USB-RS485 (Fig-
ure 12).
4. If the connecon is successful, the ST-601 sensor and its Serial Number (SN) will be displayed in the
le pane of the uPyxis® window.
*NOTE*Aer the sensor and Bluetooth is powered up, it may take up to 10 seconds for the
adapter to establish the wireless signal for communicaon.
Figure 12.
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6.3 Informaon Screen
Once connected to the device, a picture of the device will appear on the top le corner of the window and
the uPyxis® Desktop App will default to the Informaon screen. On the Informaon screen you can set the
informaon descripon for Device Name,Product Name, and Modbus Address, then click Set to save.
Figure 13.
6.4 Calibraon Screen
To calibrate the device, click on Calibraon. On the Calibraon screen there are three calibraon tabs, Zero
Calibraon,Slope Calibraon, and 4-20mA Span. The screen also displays the reading of the device. The
reading refresh rate is every 4 seconds.
Figure 14.
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6.5 Diagnosis Screen
Aer the device has been calibrated and installaon has been completed, to check diagnosis, click on Diag-
nosis. When in the Diagnosis screen you can view the Diagnosis Condion of the device. This feature may
be used for technical support when communicang with [email protected]om.
To preform a Cleanliness Check, rst select the Diagnosis Condion which denes the uid type that the
ST-601 sensor in currently measuring, then click Cleanliness Check. If the sensor is clean, a green Clean
message will be shown. If the sensor is severely fouled, a red Dirty message will be shown. In this case,
follow the procedure in the Methods to Cleaning the ST-601 Sensor secon of this manual.
Figure 15.
7 Outputs
7.1 4–20mA Output Setup
The 4–20mA output of the ST-601 sensor is scaled as:
• Chlorine Dioxide concentraon:
–4 mA = 0%
–20 mA = 0.35%
• Temperature:
–4 mA = 32 °F (0 °C)
–20 mA = 212 °F (100 °C)
ST-601 User Manual [email protected] | [phone]

7.2 Adjusng 4–20mA Span
Users may adjust the output scale using 4–20mA Span to change the ClO2 concentraon % value corre-
sponding to the 20 mA output via uPyxis®. For the uPyxis® Mobile App, press 4-20mA Span found on the
Calibraon and Reading Screen, shown in Figure 16. For the uPyxis® Desktop App, click 4-20mA Span
found on the Calibraon Screen, shown in Figure 17.
Figure 16.
Figure 17.
7.3 Communicaon using Modbus RTU
The ST-601 sensor is congured as a Modbus slave device. In addion to the ClO2 concentraon % value,
many operaonal parameters, including warning and error messages, are available via a Modbus RTU con-
necon. Contact Pyxis Lab Customer Service ([email protected]) for more informaon.
ST-601 User Manual [email protected] | [phone]

8 Sensor Maintenance and Precauon
The ST-601 sensor is designed to provide reliable and connuous bleach readings even when installed in
moderately contaminated industrial cooling waters. Although the opcs are compensated for the eects
of moderate fouling, heavy fouling will prevent the light from reaching the sensor, resulng in low readings
and the potenal for product overfeed if the ST-601 sensor is used as part of an automated control system.
When used to control product dosing, it is suggested that the automaon system be congured to provide
backup to limit potenal product overfeed, for example by liming pump size or duraon, or by alarming if
the pumping rate exceeds a desired maximum limit.
The ST-601 sensor is designed to be easily removed, inspected, and cleaned if required. It is suggested
that the ST-601 sensor be checked for fouling and cleaned/calibrated on a monthly basis. Heavily contam-
inated waters may require more frequent cleanings. Cleaner water sources with less contaminaon may
not require cleaning for several months.
8.1 Methods to Cleaning the ST-601
Any equipment in contact with industrial cooling systems is subject to many potenal foulants and con-
taminants. Our inline sensor cleaning soluons below have been shown to remove most common foulants
and contaminants. A small, so bristle brush, Q-Tips coon swab, or so cloth may be used to safely clean
the sensor housing and the quartz opcal sensor channel. These components and more come with a Pyxis
Lab Inline Probe Cleaning Soluon Kit (P/N: SER-01) which can be purchased at our online Estore/Catalog
hps://pyxis-lab.com/product/probe-cleaning-kit/
Figure 18. Inline Probe Cleaning Soluon Kit
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