Pyxis ST-712SS User manual

ST-712SS User Manual [email protected] | [phone]

ST-712SS Stainless Steel pH+ORP Sensor
User Manual
January 14, 2022
Rev. 0.92
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 4
3.1 Standard Accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
3.2 Oponal Accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
4 Installaon 5
4.1 Piping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
4.2 Wiring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
4.3 Connecng via Bluetooth . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
5 Setup and Calibraon with uPyxis® Mobile App 7
5.1 Download uPyxis® Mobile App . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
5.2 Connecng to uPyxis® Mobile App . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
5.3 Calibraon Screen and Reading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
5.4 Diagnosis Screen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
5.5 Device Info Screen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
6 Setup and Calibraon with uPyxis® Desktop App 11
6.1 Install uPyxis® Desktop App . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
6.2 Connecng to uPyxis® Desktop App . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
6.3 Informaon Screen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
6.4 Calibraon Screen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
6.5 Diagnosis Screen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
7 Outputs 15
7.1 4–20mA Output Setup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
7.2 Communicaon using Modbus RTU . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
8 Sensor Maintenance and Precauon 16
8.1 Methods to Cleaning the ST-712SS Sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
8.2 Replacing pH+ORP Electrode Head (EH-712) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
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-712SS User Manual [email protected] | [phone]

1 Introducon
Pyxis introduces the ST-712SS in-line pH/ORP composite smart sensor with built-in transmier that supports
digital (RS-485) and dual analog (4-20mA) signal outputs, designed to simplify eld installaon, calibraon
and use of operaons. The ST-712SS pH poron of the sensor is oers a at-bubble sensor design which
is opmally suited for increased fouling resistance. The sensor is designed with a large capacity salt bridge
and integrated automac temperature compensaon ensuring a highly accurate, long-life sensor with dra-
macally reduced eld maintenance. The ST-712SS ORP poron of the sensor oers an oversized planum
electrode also instrumental in ensuring long sensor life and superior accuracy in fouled waters.
The ST-712SS sensor oers an easily replaceable, front loading electrode head for pH and ORP (EH-712)
that has been independently developed by Pyxis Lab. The at front-end design of the ST-712SS makes this
plaorm less prone to contaminaon and fouling and is easy to clean. The ST-712SS sensor body is com-
posed of 304 stainless steel and is well suited for aggressive industrial applicaons. The ST-712SS sensor
oers both dual 4-20mA and RS-485 Modbus fully integrated output signals and is Bluetooth enabled when
used in conjuncon with the MA-CR Bluetooth Adapter for wireless data trending, diagnoscs and calibra-
on via uPyxis® Mobile or Desktop App.
1.1 Main Features
The ST-712SS sensor includes the following features:
• Easily replaceable electrode head (EH-712)
• Accurate and stable measurement with ultra-low dri
• Built-in transmier without preamplier or meter head
• Dual Outputs both 2x 4-20mA isolated signal or RS-485 Modbus
• Long-distance transmission with higher stability & accuracy
• Wireless Calibraon, Diagnoscs, Data Trend via uPyxis® App when used with MA-CR Adapter
ST-712SS User Manual [email protected] | [phone]

2 Specicaons
Table 1. ST-712SS Specicaons
Specicaon*ST-712SS
Part Number
(P/N)
53032
ORP Range ±1500 mV
Precision ±1 mV or 1% of the value
pH Range
(4-20mA
Output)
0.00–14.00
With Automac Temperature Compensaon
Precision ±0.01 pH unit or 1% of the value
Response Time 95% within 5 seconds
Power Supply 22–26V DC, Power Consumpon 2W
Storage
Temperature
-7–60 °C (20–140 °F)
Outputs Isolated Dual 4–20 mA Analog Output & isolated RS-485 Digital Output
Dimension (L ×
W×H)
Length 6.8 inch (172.7 mm), body diameter 1.44 Inch (36.6 mm)
Installaon ST-001 Inline Tee (provided) 3/4” FNPT Glue & Thread
Body Material 304 stainless steel
Weight 530 g (1.16 lbs)
Operaonal
Pressure
100 psi (6.9 bar)
Operang
Temperature
4–40 °C (40–104 °F)
Wet Material Quartz & UPVC
Rang IP67, Fully Dustproof & Waterproof
Regulaon CE Marked
Cable Included MA-4.9CR Cable (8Pin Male/Female Adapters — 4.9)
MA-1.5CR Cable (8 Pin Male Adapter / Flying Leads — 4.9)
Addional Extension Cables Available
Typical Service
Life †
2 years
*With Pyxis’s connuous improvement policy, these specicaons are subject to change without noce.
†Typical life is the sensor at 25 °C temperature under normal use condions to measure clear water; harsh working
condions or water quality may shorten life.
ST-712SS User Manual [email protected] | [phone]

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
• One ST-712SS sensor with one ST-001 (CPVC) Inline Tee Assembly
• One MA-4.9CR — (Standard Cable / Male-Female 8-Pin Adapters — 4.9ft)
• One MA-1.5CR — (Flying Lead Cable / Male 8-Pin Adapter and Flying Leads —
4.9ft)
• User Manual available online at https://pyxis-lab.com/support/
3.2 Oponal Accessories
The following oponal accessories can be ordered from Pyxis Customer Service ([e-mail]) or
Pyxis E-Store at hps://pyxis-lab.com/shop/.
Table 2. Oponal Accessories
ST-712SS User Manual [email protected] | [phone]
Accessory Name/Description Part Number
EH-712
(Replacement pH + ORP Electrode Head for ST-712SS) 53035
ST-007
(Stainless Steel Inline Tee Assembly ¼-inch Swagelok Inlet/Outlet) 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) MA-NEB
MA-50CR
(8-Pin Extension Cable-50 feet) 50743
PowerPACK-2
(Dual Channel Powered Bluetooth Adapter w 2x 4-20mA Pass Through) MA-BLE-2
ORP-200mV Calibration Standard Solution
(Calibration Solution 500mL) 57020
4-7-10 Combination pH Calibration Kit
(4-7-10 pH Calibration Solution 500mL Each) 57007

4 Installaon
Figure 1. Dimension of the ST-712SS sensor (mm)
4.1 Piping
The provided ST-001 Tee Assembly can be connected to a pipe system through the 3/4” female ports, either
socket or NPT threaded. To properly install the ST-712SS 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-712SS sensor into the tee.
3. Tighten the tee nut onto the tee to form a water-ght, compression seal.
Figure 2. Installaon structure diagram of ST-712SS
ST-712SS User Manual [email protected] | [phone]

4.2 Wiring
If the power ground terminal and the negave 4–20mA terminal in the controller are internally connected
(non-isolated 4–20mA input), it is unnecessary to connect the 4–20mA negave wire (gray) to the 4–20mA
negave terminal in the controller. If a separate DC power supply other than that from the controller is
used, make sure that the output from the power supply is rated for 22–26 VDC @ 85 mA.
*NOTE*The negave 24V power terminal (power ground) and the negave 4–20mA ter-
minal on the ST-712SS sensor are internally connected.
Follow the wiring table below to connect the ST-712SS sensor to a controller:
Table 3.
Wire Color Designaon
Red 24V +
Brown 24V Power ground
White pH 4–20mA +
Gray*4–20mA -
Blue RS-485 A
Yellow RS-485 B
Pink ORP 4–20mA +
Green Earth ground
Black Shield, soluon ground
*Internally connected to the power ground
4.3 Connecng via Bluetooth
Connect and power the ST-712SS sensor with the Pyxis Bluetooth adapter (P/N: MA-CR) installed as shown
in the following connecon diagram. The power should be sourced from a 24 VDC power terminal of a
controller. If a controller is not available, please purchase a 24 V power supply. Alternavely, you may pur-
chase a Pyxis PowerPACK-1 Auxiliary Bluetooth Adapter that can provide power supply, Bluetooth access,
and 4-20mA signal passthrough to the ST-712SS sensor. See Oponal Accessories secon for details.
ST-712SS User Manual [email protected] | [phone]
Figure 3. Bluetooth connection to ST-710SS sensor with MA-CR and uPyxis Mobile App.

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 4. uPyxis® Mobile App installaon
ST-712SS User Manual [email protected] | [phone]

5.2 Connecng to uPyxis® Mobile App
Connect the ST-712SS 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-712SS and its Serial Number (SN) will be displayed (Figure 5).
4. Press on the ST-712SS sensor image.
Figure 5.
ST-712SS User Manual [email protected] | [phone]

5.3 Calibraon Screen and Reading
The ST-712SS pH/ORP sensor is rigorously calibrated before leaving the Pyxis factory. As such, users should
not need to calibrate the sensor for a period of three months up to one year if the sensor is maintained in
clean operable condion. In applicaons where the sensor may become dirty or fouled (i.e. Cooling Tow-
ers) users can calibrate the sensor according to their needs and as desired.
The ST-712SS sensor requires calibraon for pH/ORP. The pH/ORP can be calibrated with a standard so-
luon containing a known pH/ORP or with the sample water itself. The pH/ORP of the sample water should
be determined with a properly calibrated benchtop or portable pH/ORP analyzer, such as the Pyxis SP-600
(Portable Water Mulmeter). Before calibraon, the ST-712SS sensor should be cleaned with Pyxis Probe
Cleaning Soluon (P/N: SER-01) if heavily fouled then thoroughly rinsed with deionized water taking special
care to avoid direct contact with the electrode by the ngers or hand.
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 pH Low Calibraon,pH 7 Calibraon,pH High Calibra-
on, and ORP Calibraon. Follow the screen instrucons for each calibraon step.
Figure 6.
ST-712SS 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].
Figure 7.
5.5 Device Info Screen
From the Device Info screen. You can name the Device or Product as well as set the Modbus address.
ST-712SS User Manual [email protected] | [phone]

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 9. uPyxis® Desktop App installation
Click Install to start the installaon process. Follow the screen instrucons to complete the USB driver and
uPyxis® installaon.
ST-712SS User Manual [email protected] | [phone]
Figure 8. Bluetooth connection to ST-710SS Sensor with MA-CR and MA-NEB and uPyxis Desktop.

6.2 Connecng to uPyxis® Desktop App
Connect the ST-712SS sensor to a Windows computer using a Bluetooth/USB adapter (P/N: MA-NEB) ac-
cording to the following steps:
1. Plug the Bluetooth/USB adapter into a USB port in the computer.
2. Launch uPyxis® Desktop App.
3. On uPyxis® Desktop App, click Device →Connect via USB-Bluetooth (Figure 9).
4. If the connecon is successful, the ST-712SS 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 10.
ST-712SS User Manual [email protected] | [phone]

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 11.
ST-712SS User Manual [email protected] | [phone]

6.4 Calibraon Screen
The ST-712SS pH/ORP sensor is rigorously calibrated before leaving the Pyxis factory. As such, users should
not need to calibrate the sensor for a period of three months up to one year if the sensor is maintained in
clean operable condion. In applicaons where the sensor may become dirty or fouled (i.e. Cooling Tow-
ers) users can calibrate the sensor according to their needs and as desired.
The ST-712SS sensor requires calibraon for pH/ORP. The pH/ORP can be calibrated with a standard so-
luon containing a known pH/ORP or with the sample water itself. The pH/ORP of the sample water should
be determined with a properly calibrated benchtop or portable pH/ORP analyzer, such as the Pyxis SP-600
(Portable Water Mulmeter). Before calibraon, the ST-712SS sensor should be cleaned with Pyxis Probe
Cleaning Soluon (P/N: SER-01) if heavily fouled then thoroughly rinsed with deionized water taking special
care to avoid direct contact with the electrode by the ngers or hand.
To calibrate the device, click on Calibraon. On the Calibraon screen there is are four calibraon buons,
pH 7 Calibraon,pH Low Calibraon,pH High Calibraon, and ORP Calibraon. The screen also displays
the reading of the device. The reading refresh rate is every 4 seconds. Follow the screen instrucons for
each calibraon step.
Figure 12.
ST-712SS User Manual [email protected] | [phone]

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].
Figure 13.
7 Outputs
7.1 4–20mA Output Setup
The 4–20mA output of the ST-712SS sensor is scaled as:
• pH:
–4 mA = 0
–20 mA = 14
• ORP:
–4 mA = -1500 mV
–20 mA = 1500 mV
7.2 Communicaon using Modbus RTU
The ST-712SS sensor is congured as a Modbus slave device. In addion to the pH value and ORP mV
value, many operaonal parameters, including warning and error messages, are available via a Modbus
RTU connecon. Contact Pyxis Lab Customer Service ([email protected]) for more informaon.
ST-712SS User Manual [email protected] | [phone]

8 Sensor Maintenance and Precauon
8.1 Methods to Cleaning the ST-712SS Sensor
Any equipment in contact with industrial cooling systems is subject to many potenal foulants and contam-
inants. 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 E-Store hps://pyxis-
lab.com/product/st-series-probe-cleaning-kit/
Figure 14. Inline Probe Cleaning Solution Kit
To clean the ST-712SS sensor, soak the lower half of the sensor in 100 mL inline sensor cleaning soluon for
10–15 minutes. Rinse the ST-712SS sensor with dislled water. If the surface is not enrely clean, connue
to soak the ST-712SS sensor for an addional 10–15 m inutes. Use the small, so bristle brush and Q-Tips
coon swabs as necessary to remove any remaining contaminants on the ST-712SS sensor surface.
ST-712SS User Manual [email protected] | [phone]

8.2 Replacing pH+ORP Electrode Head (EH-712)
The ORP electrode head of ST-712SS can be purchased as a spare accessory under the name EH-712 (P/N:
53035) can be replaced when the original electrode head reaches the end of its working life. Order a re-
placement electrode head (EH-712) from Pyxis and follow instrucons as below:
1. Turn o the sensor if it is powered on.
2. Make sure there is no water on the sensor.
3. Hold the ST-712SS main body with one hand and use the other hand to twist the stainless-steel locking
ring connecting the black electrode counterclockwise, until the front end of the black electrode is
completely unscrewed, as shown in Figure 15-2.
4. Pull out the electrode head as show in Figure 15-3.
5. Gently loosen the electrode plug connector and remove the electrode head as show in Figure 15-4.
6. To assemble the new electrode head, gently insert the plug connector and push the wires into the
main housing. Gently insert the new electrode head into the sensor main body. The two protrusions
on the electrode head should be aligned with the notch in the sensor main housing.
7. Then twist the stainless-steel lock ring of ST-712SS in a clockwise direction until the threads of the
electrode head basically enter the ST-712SS housing, as shown in 15-1.
ST-712SS User Manual [email protected] | [phone]