Pyxis ST-765SS-03 User manual

V1.07

ST-765SS-O3 Sensor Manual
[e-mail] | [phone]
2
Table of Contents
1. Introducing the Pyxis ST-765SS-O3 Sensor ......................................................................................................4
1.1 Specifications ............................................................................................................................................................ 5
1.2 Unpacking the ST-765SS-O3...................................................................................................................................... 5
1.3 Standard Accessories................................................................................................................................................ 6
1.4 Optional Accessories............................................................................................................................................... 6
2. Dimension & Installation................................................................................................................................7
3. Quick 4-20mA Start Up.................................................................................................................................10
4. Calibration and Diagnosis.............................................................................................................................11
4.1 Calibration and Diagnosis by uPyxis Mobile App .................................................................................................... 11
4.1.1 Ozone Calibration............................................................................................................................................ 13
4.1.2 pH Calibration ................................................................................................................................................. 14
4.1.3 4-20mA Span................................................................................................................................................... 15
4.1.4 Diagnosis ......................................................................................................................................................... 15
4.2 Calibration and Diagnosis by uPyxis Desktop App................................................................................................... 16
4.2.1 Ozone Calibration............................................................................................................................................ 19
4.2.2 pH Calibration ................................................................................................................................................. 19
4.2.3 4-20mA Span................................................................................................................................................... 21
4.2.4 Diagnosis ......................................................................................................................................................... 22
5. Calibration on the Controller.........................................................................................................................22
6. Modbus RTU .................................................................................................................................................22
7. Sensor Cleaning and Maintenance..................................................................................................................23
7.1 Other Common Troubleshooting Issues ................................................................................................................. 23
8. Replacing pH and Oxidizer Electrode Head .....................................................................................................24
9.Contact Us...................................................................................................................................................25

ST-765SS-O3 Sensor Manual
[e-mail] | [phone]
3
Warranty Information
Confidentiality
The information contained in this manual may be confidential and proprietary and is the property of Pyxis
Lab, Inc. Information disclosed herein shall not be used to manufacture, construct, or otherwise reproduce
the goods described. Information disclosed herein shall not be disclosed to others or made public in any
manner without the express written consent of Pyxis Lab, Inc.
Standard Limited Warranty
Pyxis Lab warrants its products for defects in materials and workmanship. Pyxis Lab will, at its option, repair
or replace instrument components that prove to be defective with new or remanufactured components
(i.e., equivalent to new). The warranty set forth is exclusive and no other warranty, whether written or oral,
is expressed or implied.
Warranty Term
The Pyxis warranty term for the ST-765SS Series sensor body is thirteen (13) months from original
shipment from Pyxis. The Pyxis warranty term for the EH-765 (electrode reference head) installed on the
ST-765SS Series sensor body is six (6) months from original shipment from Pyxis. In no event shall the
standard limited warranty coverage extend beyond this timeline from original shipment date.
Warranty Service
Damaged or dysfunctional instruments may be returned to Pyxis for repair or replacement. In some in-
stances, replacement instruments may be available for short duration loan or lease.
Pyxis warrants that any labor services provided shall conform to the reasonable standards of technical com-
petency and performance effective at the time of delivery. All service interventions are to be reviewed and
authorized as correct and complete at the completion of the service by a customer representative, or des-
ignate. Pyxis warrants these services for 30 days after the authorization and will correct any qualifying
deficiency in labor provided that the labor service deficiency is exactly related to the originating 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-
corporation of a warranted repair component into an instrument extend the whole instrument’s warranty
beyond its original term.
Warranty Shipping
A Repair Material Authorization (RMA) 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 https://pyxis-lab.com/request-tech-support/.
Pyxis Technical Support
Contact Pyxis Technical Support at [phone], [e-mail] or by filling out a request for
support at https://pyxis-lab.com/request-tech-support/.

ST-765SS-O3 Sensor Manual
[e-mail] | [phone]
4
1. Introducing the Pyxis ST-765SS-O3 Sensor
Description
The Pyxis ST-765SS-O3 is a stainless-steel multi-parameter membrane-less
sensor based on unique electrochemical principles to determine Ozone plus
pH and temperature of water. This sensor incorporates Pyxis' advanced
technology in the field of bare-gold electrochemical detection. The ST-765SS-
O3 can simultaneously compensate for temperature and pH in the
measurement of Ozone based on real-time conditions present in the
application of use. This unique internal compensation results in a highly
accurate oxidizer measurement consistent with DPD wet chemistry
methodology as high as a pH of 9.0+ and is compliant with USEPA –334.0 and
ISO-7393 guidelines.
The ST-765SS-O3 sensor offers a replaceable, front loading reference
electrode assembly that has been independently developed by Pyxis Lab
eliminating the shortcomings associated with membranes and gel
replacement while offering reduced polarization time on startup with an
electrode life span potential of up to 2-years. The flat front-end design of the
ST-765SS-O3 makes this platform less prone to contamination or fouling and
is easy to clean. The ST-765S-O3 sensor body is composed of 304 stainless
steel and is well suited for aggressive environments.
The ST-765SS-O3 sensor offers 2x 4-20mA and RS-485 Modbus outputs and is
Bluetooth 5.0 enabled when used in conjunction with the MA-CR Bluetooth
Adapter. This four-electrode composite sensor provides three measured
parameters including Ozone, pH and temperature with one sensor equipped
with fully integrated 2x 4-20mA and RS-485 Modbus outputs. ST-765SS-O3 is
uniquely designed for rapid and precise monitoring of disinfection process
water applications utilizing Ozone.
Key Features
•Real-Time pH + Oxidizer (0-5ppm) Detection
•Dual 4-20mA Outputs (Oxidizer + pH) and RS-485
•Bluetooth Enabled when used with MA-CR Adapter Wireless uPyxis Calibration
•Integrated RTD & pH Compensation to pH 9.0+ of the Oxidizer Value
•Replaceable EH-765 Reference Electrode Assembly –Simple Maintenance
Common Applications
•Bottled Water Filler Production
•Spring Water Transport Disinfection
•Food / Beverage Processing Equipment Sanitizing
•Conveyors / Flume Water
•Irrigation & Process Water
ST-765SS-O3
Ozone + pH Sensor
EH-765
Replacement Electrode
for all ST-765SS Series

ST-765SS-O3 Sensor Manual
[e-mail] | [phone]
5
1.1 Specifications
Item
ST-765SS-O3
P/N
53614
Sensor Body Material
304SS
Oxidizer Range
0.00-2.00 ppm Ozone
Oxidizer Precision
± 0.01mg/L or 1% of the value w/pH compensation up to 9.0+
pH Range
0-14
pH Precision
±0.01 pH
Sample Inlet Pressure
7.25 –30 psi (0.05 –0.2MPa)
Installation
ST-007 Stainless Steel Flow Cell Assembly (Sold Separately)
ST-007 Minimum Flow Rate
200 mL/minute
ST-007 Maximum Flow Rate
400 mL/minute
ST-007 Sample Inlet
¼ - inch OD
ST-007 Sample Outlet
¼ - inch OD
Power Supply
22 –26VDC, Power Consumption 2W
Storage Temperature
-7 °C –60 °C (20 –140 °F)
Outputs
Dual Isolated 4 –20 mA Analog Outputs + Isolated RS-485 Digital Output
Dimension (L x D)
Length 8.3 inch (210.8 mm), body diameter 1.4 Inch (35.6 mm)
Weight
530 g (1.16lbs)
Maximum Sensor Pressure
100 psi (6.9 Bar) –Sensor Only
Operating Temperature
4 °C –49 °C (40 –120 °F)
Wet Material
UPVC
Rating
IP67, Fully Dustproof & Waterproof
Selectivity
Non-Selective / Cross Sensitive to other Oxidizing Species
Compliance
EPA 334.0 / ISO 7393
Regulation
CE Marked / RoHS
Cables Included
MA-4.9CR Cable (8Pin Adapter –4.9ft)
MA-1.5CR Cable (8 Pin Adapter / Flying Leads –1.5ft)
Typical Electrode Service Life
2 Years
Electrode Warranty
6 Months
Sensor Body Warranty
13 Months
*NOTE* Specifications are subject to change without notice.
1.2 Unpacking the ST-765SS-O3
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 items listed on the packing slip are included. If any
items are missing or damaged, please contact Pyxis Customer Service at [email protected]

ST-765SS-O3 Sensor Manual
[e-mail] | [phone]
6
1.3 Standard Accessories
•One ST-765SS-O3 Series sensor (P/N: 53614)
•Includes One MA.4.9CR –(Standard Cable Male-Female 8-Pin Adapters –4.9ft)
•Includes One MA-1.5CR –(Flying Lead Cable Female/Flying Lead 8-Pin Adapter –1.5ft)
•The full instrument manual is available for download at Support Documents - Pyxis Lab, Inc. (pyxis-
lab.com)
1.4Optional Accessories
The following optional accessories can be purchased via [email protected]om or your preferred Pyxis Lab
distributor.
Accessory Name
Item number
EH-765
(Replacement Reference Electrode Head for ST-765SS Series)
53601
ST-007
(Replacement ST-007 Stainless Steel Flow Cell)
50700-A51
MA-CR
(Bluetooth Adapter For use with Pyxis 8-Pin Sensors)
MA-CR
MA-NEB
(USB Bluetooth Adapter for use with Laptop or Desktop for uPyxis)
MA-NEB
MA-50CR
(Extension Cable-50 feet)
50743
UC-80
(Display + Data Logging Terminal)
14003
pH4-7-10 Combination Pack - Reference Standard Solutions
(500mL/each)
57007
SP-200 OxiPocket
(Pocket All-Oxidizing Disinfectants Colorimeter & Fluorometer)
50802
IK-765SS-O3
(ST-765SS-O3 Sensor + ST-007 Flow Cell + UC-80 Display/Data Logger Panel Mounted)
42091

ST-765SS-O3 Sensor Manual
[e-mail] | [phone]
7
2. Dimension & Installation
The ST-765SS-O3 should be installed in the ST-007 stainless steel inline sensor tee assembly for optimum
accuracy. Ozone is highly oxidative and rapidly degrading. Stainless steel is recommended to ensure
minimal ozone depletion between injection of treatment and the sensor. The ST-007 is provided with ¼-
inch stainless steel OD inlet and outlet compression adapter (SwageLok) and it is recommended that ¼-
inch OD stainless steel tubing be utilized for sample flow. The recommended flow rate for the ST-765SS-
O3 sensor in the ST-007 inline tee assembly is 200-400mL per minute and should be controlled upstream
with rotameter. The inlet water sample pressure should be maintained between 7.5 and 30 psi with
discharge to open drain or atmospheric sump.
ST-765SS Series Dimensions (mm)
Figure 1. - Dimension of the ST-765SS (mm)
ST-007 Flow Cell Dimensions (mm)
Figure 2. - ST-007 Flow cell for ST-765SS -O3

ST-765SS-O3 Sensor Manual
[e-mail] | [phone]
8
IK-765SS-O3 Ozone + pH + Temperature Online Monitoring Panel
For clients desiring a ‘turn-key’ ozone analyzer, Pyxis Lab offers the OxiPanel IK-765SS-O3. The IK-765SS-O3 is
a pre-assembled Ozone + pH + Temperature monitoring panel consisting of the ST-765SS-O3 (Ozone) sensor
with mounted ST-007 flow cell with 316L stainless steel interconnecting tubing, rotameter, digital flow sensor
and the UC-80 Display + Data Logging Terminal. This platform solution offers real-time display, data logging
and signal output capability of sample Ozone, pH and temperature.
The UC-80 is a microprocessor display/data-logging terminal that has been preconfigured to connect Pyxis
inline sensors with fully integrated calibration, scaling and measurement protocol. The user may also
configure and calibrate the output signal through the UC-80 controller's screen. The IK-765SS-O3 detection
system can be applied to a clean water applications including bottled water production, drinking water
networks, secondary water supply and alternative clean-water ozone treatment applications.
Image and Dimensions of IK-765SS Series (mm)
Figure 3 –IK-765SS-O3 Series Panel
Item
P/N
Description
IK-765SS-O3
42091
ST-765SS-O3 Sensor + ST-007 Flow Cell + UC-80 Display/Data Logger

ST-765SS-O3 Sensor Manual
[e-mail] | [phone]
9
Specifications of UC-80 Display/Data Logging Terminal
Dimensions of UC-80 (mm)
Item
UC-80
P/N
14003
Measurement Interval
Continuous Measurement
Display
4.3-inch LCD Color Industrial Capacitive Touch Screen
Storage Capacity
Built-In 128MB of Ram for Storing up to 1-Million Data/Event Records
Power Requirement
96-260VAC / 50-60 Hz; 200 W
Output
2 x 4-20 mA / RS-485 Modbus - RTU / Modbus TCP
Input
RS-485 Modbus - RTU
USB
1 x USB host, for data downloading and screen upgrade
Internet
RJ-45 socket, Modbus-TCP –For Pyxis CloudLinkTM
Panel Operational Temperature
40 –113oF (4-45 oC)
Storage Temperature
Instrument: -4 –131oF (-20 –55oC)
Sample Water Temperature
40 –104oF (4-40oC)
Rating
IP-65 Panel-Display
Regulation
CE / RoHS
Relative Humidity
20% - 90% (No Condensation)
Altitude
<6,561 feet (<2,000 Meter)
Dimensions (HxWxD)
H250×W150×D100mm
Approximate Product Weight
~ 5 kg

ST-765SS-O3 Sensor Manual
[e-mail] | [phone]
10
3. Quick 4-20mA Start Up
Follow the wiring table below to connect the ST-765SS-O3 sensor to a controller or PLC. *NOTE* All Pyxis sensors
provide a passive 4-20mA output signal, they are NOT LOOP POWERED. 24VDC+ power supply and 4- 20mA+
signal are independent of each other in all Pyxis Lab sensors.
Wire Color Designation
Red 24 V +
Brown Power Ground
Green Shield, solution ground
Gray 4-20 mA -
White 4-20 mA+forOzone
Pink 4-20 mA +forpH
Blue RS-485 A
Yellow RS-485 B
Black Shield, solution ground
ST-765SS-O3 Sensor 4-20mA Scaling
Unit of Measure 4mA Value 20mA Value
pH 0.00 pH 14.00 pH
Ozone 0.00 ppm 2.00 ppm
*NOTE* If the 24V power ground and the 4-20 mA-return in the controller are internally connected (non-
isolated 4-20mA input), it is unnecessary to connect the 4-20 mA- (Gray wire) to the 4-20 mA negative terminal
in the controller. If a separate DC power supplier other than that from the controller is used, make sure that
the output from the power supply is rated for 22-26 VDC @ 85mA.
*NOTE* Pyxis recommends the 24VDC power supply to the ST-765 series sensor be turned OFF for systems
that experience extended periods of stagnant water conditions exceeding one hour in duration. Upon sensor
power-up, the ST-765 series will complete a 5-minute electrode initialization to remove any oxide layer from
the gold electrode which accumulates during stagnation. The sensor will output 1mA for oxidizer/reducer
during this initialization process and return to its normal reading with 4-20mA output once complete.

ST-765SS-O3 Sensor Manual
[e-mail] | [phone]
11
4. Calibration and Diagnosis
The ST-765SS Series sensors are rigorously calibrated before leaving the factory. As such, users do not need
to calibrate the sensor for a period of three months or up to one year if the sensor is maintained in clean
condition. Users can however calibrate the sensor according to their application needs and as desired using
the MA-CR Bluetooth adapter and uPyxis APP for mobile or desktop devices.
4.1 Calibration and Diagnosis by uPyxis Mobile App
Connect and power the ST-765SS sensor using the MA-CR Pyxis Bluetooth adapter (P/N: MA-CR) as shown
in the following connection diagram. The power should be sourced from a 24 VDC power terminal of a
controller. If a controller is not available, please purchase a 24VDC power supply.
Figure 4. - Power the ST-765SS and MA-CR via USB
MA-CR Bluetooth Adapter

ST-765SS-O3 Sensor Manual
[e-mail] | [phone]
12
Download and install the uPyxis app from Apple iStore or Google Play. Turn on the
Bluetooth in the smart device (please do not pair your device Bluetooth to uPyxis,
the app will do the pairing). Open the uPyxis app in the device. Swipe down to
refresh the screen to scan the available Pyxis Bluetooth devices. The discovered
devices will be listed as shown in Figure 6.
Tap the discovered ST-765SS sensor to connect to the sensor. The uPyxis app can
identify the sensor type if multiple Pyxis sensors are discovered in the scan.
As shown in Figure 6, in the calibration page of uPyxis after connected to the sensor via the MA-CR
Bluetooth adapter the current Ozone, pH and temperature values will be displayed. Six functional tabs of each
are available in this page: Zero Calibration, Slope Calibration, pH Low Calibration, pH 7 Calibration, pH High
calibration and 4-20mA Span.
Figure 5 - ST-765SS Discovered via Bluetooth Figure 6 - Calibration Page

ST-765SS-O3 Sensor Manual
[e-mail] | [phone]
13
4.1.1 Ozone Calibration
The measurement module of the ST-765SS-O3 sensor is thoroughly calibrated at the Pyxis Lab factory. To
calibrate, the user can perform a single-point calibration according to the requirements of the application.
(USEPA-334.0 / ISO-7393 compliant methodology)
Calibration of the ST-765SS-O3 sensor for ozone should be done with the sensor inline exposed to active
flowing sample water. Use a portable or laboratory colorimeter (i.e.. Pyxis SP-200 / SP-800 / SP-910 or similar)
to test the active (flowing) water sample in the flow tee assembly. Once you have tested and confirmed the
Ozone concentration value in the active (flowing) flow tee assembly, Tap SLOPE CALIBRATION and enter the
test result value of the portable or laboratory colorimeter in Calibration Screen as shown in Figure 7. For best
results, the concentration of the Ozone sample flow standard should be in the range of 0.1 to 2.00 ppm.
Figure 7 - Enter Test Confirmed Ozone Concentration to begin Slope Calibration

ST-765SS-O3 Sensor Manual
[e-mail] | [phone]
14
4.1.2 pH Calibration
Remove and place the sensor in a low pH (i.e.. 4.0) calibration standard solution and tap pH LOW
CALIBRATION in the uPyxis app. Measure for 1 minuteand wait for the measurement result to stabilize before
performing calibration, the low pH calibration standard value range acceptable for this step is 1.00-6.00 pH.
Place the sensor into the pH 7.0 calibration standard solution and tap pH 7 CALIBRATION in the uPyxis app.
Measure for 1 minute and wait for the measurement result to stabilize before performing calibration.
Place the sensor in a high pH (i.e.. 10.0) calibration standard solution and tap pH HIGH CALIBRATION in the
uPyxis app. Measure for 1 minute and wait for the measurement result to stabilize before performing
calibration, the high pH calibration standard value range acceptable for this step is 8.00-13.00 pH.
Figure 8 Figure 9
Enter Low-pH Concentration for Calibration Enter High-pH Concentration for Calibration

ST-765SS-O3 Sensor Manual
[e-mail] | [phone]
15
4.1.3 4-20mA Span
The 4–20mA output of the ST-765SS-O3 sensor is scaled as:
•Ozone:
– 4 mA = 0 ppm
–20 mA = 2 ppm
Tap 4-20mA SPAN to change the Ozone value corresponding to the 20mA output to a lower value as seen
in Figure 10. *NOTE* The 4-20mA Span feature allows users to REDUCE the upper 20mA output scale only.
You cannot INCREASE the upper limit of the sensor beyond the range of the sensor.
Figure 10 –Adjust 20mA Setting for Ozone (<2ppm)
Figure 11 - Diagnostic Interface
4.1.4 Diagnosis
Tap Diagnosis in the bottom of the app page to launch the diagnosis page Figure 11.
In this page, the raw data measured by the sensor is displayed. To help troubleshooting possible issues with
the sensor, please save images of these data when the sensor is respectively placed in a clean water (tap
water or deionized water), in a pH standard solution, and in the sample that the sensor is intended for. This
data may be exported from the uPyxis APP via email to service@pyxis- lab.com for technical support.

ST-765SS-O3 Sensor Manual
[e-mail] | [phone]
16
4.2 Calibration and Diagnosis by uPyxis Desktop App
1) Download and install uPyxis Desktop APP from
https://upyxis.pyxis-lab.com.cn/release/pc/uPyxis.Setup-latest.zip
2) Connect a USB Type-C cable to the port at the bottom of the MA-CR and to the USB port of the laptop or
computer. This will provide power the MA-CR from the laptop/computer. Connect the MA-CR to the ST-765SS-
O3 sensor. The MA-CR Bluetooth adapter will boost the 5V of the regular USB to 24V to power the sensor for
use with uPyxis Desktop.
Figure 12 –MA-CR Connected to Sensor & Laptop
3) Set the MA-CR to operate in USB Mode by following the steps below.
a. Once the MA-CR screen is powered Press or until you arrive at (USB to RS485)
screen.
b. Press the Button.
c. Follow Prompts below to Enable USB feature. Once enabled, you may connect to uPyxis.
MA-CR Bluetooth Adapter –Bottom USB-C
Port

ST-765SS-O3 Sensor Manual
[e-mail] | [phone]
17
4) Open the desktop uPyxis APP.
5) Click Device to launch the connection option menu.
6) Select Connect via USB-RS485 (Figure 13).
7) Select the Comm Port to make a connection. Normally only one Comm port is identified by
uPyxis (Figure 14). If more than one Comm port listed in the selection dropdown, you may try
to select each one to see if a connection can be made. Alternatively, you may use the
Windows Device Manager to identify the Comm Port that the Pyxis USB adapter is using.
After the connection is established, the ST-765SS sensor series number and Ozone reading will be displayed
on the left of the information page Figure 15. In this page, a nickname can be assigned to the sensor. The
sensor Modbus address can also be changed if desired. Click Calibration to launch the calibration page Figure
16.
Figure 13 - Connection Options

ST-765SS-O3 Sensor Manual
[e-mail] | [phone]
18
Figure 14 - Select a Comm port
Figure 15 - Connected to ST-765SS-O3 sensor and information page
Figure 16 - Calibration Page

ST-765SS-O3 Sensor Manual
[e-mail] | [phone]
19
4.2.1 Ozone Calibration
The measurement module of the ST-765SS-O3 sensor is thoroughly calibrated at the Pyxis Lab factory. To
calibrate, the user can perform a single-point according to the requirements of the application. (USEPA-334.0
/ ISO-7393 compliant methodology)
Calibration of the ST-765SS-O3 sensor for ozone should be done with the sensor inline exposed to active
flowing sample water. Use a portable or laboratory colorimeter (i.e.. Pyxis SP-200 / SP-800 / SP-910 or
similar) to test the active (flowing) water sample in the flow tee assembly. Once you have tested and
confirmed the concentration value in the active (flowing) flow tee assembly, Tap SLOPE CALIBRATION and
enter the test result value of the portable or laboratory colorimeter in Calibration Screen as shown in Figure
7.For best results, the concentration of the Ozone sample flow standard should be in the range of 0.1 to
2.00 ppm.
Figure 17 - Slope Calibration
4.2.2 pH Calibration
Remove and place the sensor in a low pH (i.e.. 4.0) calibration standard solution and tap pH LOW
CALIBRATION in the uPyxis app. Measure for 1 minute and wait for the measurement result to stabilize before
performing calibration, the low pH calibration standard value range acceptable for this step is 1.00-6.00 pH.
Place the sensor into the pH 7.0 calibration standard solution and tap pH 7 CALIBRATION in the uPyxis app.
Measure for 1 minute and wait for the measurement result to stabilize before performing calibration. Place the
sensor in a high pH (i.e.. 10.0) calibration standard solution and tap pH HIGH CALIBRATION in the uPyxis app.
Measure for 1 minute and wait for the measurement result to stabilize before performing calibration, the
high pH calibration standard value range acceptable for this step is 8.00-13.00 pH.

ST-765SS-O3 Sensor Manual
[e-mail] | [phone]
20
Figure 18 - pH Low Calibration
Figure 19 - pH 7 Calibration
Figure 20 - pH High Calibration