Cerlic pHX User manual

2019-02-20 C60C5EN19
pHX / ReX
pH- / Redox
Sensor

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TABLE OF CONTENTS
1. Introduction ................................................................................................ 3
2. A few words about this manual ................................................................ 3
3. Design......................................................................................................... 3
4. Measuring principle ................................................................................... 3
5. Unpacking the Sensor ............................................................................... 4
6. Installing the Sensor.................................................................................. 5
Connections .................................................................................................................. 6
Installation hints............................................................................................................ 6
Starting Up.................................................................................................................... 6
7. Removing the sensor................................................................................. 6
8. Mounting the electrode.............................................................................. 7
9. Cleaning...................................................................................................... 8
Mounting plate for cleaning solenoid valves................................................................ 8
10. Maintenance ............................................................................................... 9
Error messages.............................................................................................................. 9
Broken Electrode .......................................................................................................... 9
Incorrect Measurements................................................................................................ 9
11. Sensor display ......................................................................................... 10
12. Menu for Sensors..................................................................................... 11
Menu for pHX............................................................................................................. 11
Menu for ReX ............................................................................................................. 13
13. Calibration ................................................................................................ 15
Calibrating pH ............................................................................................................ 15
Adjusting ORP............................................................................................................ 16
14. Scaling ...................................................................................................... 16
15. Technical data pHX / ReX ........................................................................ 17
16. Dimensions............................................................................................... 19
Appendix 1, Optional slide rail holder .......................................................... 20
Appendix 2, pH as a function of mV ............................................................. 21
Appendix 3, pH temperature dependency.................................................... 22
Appendix 4, Support information.................................................................. 23
Appendix 5, Setup information ..................................................................... 24

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1. Introduction
pHX / ReX are used to measure pH or Redox potential in water and wastewater
treatment plants and other industrial applications.
2. A few words about this manual
This manual details installation procedures and operational features of the Cerlic pH and
Redox sensors. Menu navigation and technical data for the BB2 control box can be
found in the BB2 service manual.
3. Design
The pHX / ReX sensors are manufactured in SIS2343 (316SS) stainless steel and PVC.
The sensors are mounted using PVC clamps. An adjustable stainless steel slide rail
holder is available as an option as well as equipment for automatic cleaning.
The sensor has a fixed, shielded 10 m (33’) cable used for signal transmission between
the sensor and the BB2 control box.
4. Measuring principle
pH is normally measured with an electrode where pH is expressed as a function of
voltage. Today's electrodes often contain both a measuring electrode and a reference
electrode, which in combination provide a voltage in linear proportion to the pH value.
Electrodes internally combined with a reference and measuring cell are divided into two
categories: gel electrodes and refillable electrodes. The gel electrode is the simpler and
less expensive type. There are a number of different types of refillable electrodes for
different applications, each with different internal solutions that are to be added at
regular intervals. Cerlic provides a gel-filled glass electrode.
The temperature of the calibration buffer and the media to be measured can be entered
in BB2 to compensate for the temperature dependence of the electrode. All settings are
made in the central unit BB2 using a self-instructing menu controlled by just three keys.
The output signal is frozen when you switch to menu mode so that the output signal will
not change during procedures such a re-calibration.
The BB2 has two 4-20 mA outputs, and relay outputs for alarm and cleaning of the
electrode.
The current pH/mV is continuously displayed in a window, maximum, minimum and
average values for the last 24 hours can be obtained by pressing two buttons.

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5. Unpacking the Sensor
The unit has been tested and approved before delivery from the supplier. Please check
to confirm that no visible damages occurred during shipment.
Damages
If damages occurred during shipment, immediately contact UPS or other truck line as
well as your Cerlic representative. The shipment can be returned only after contact has
been made with Cerlic.
Packaging
The original packaging is designed to protect the equipment and should be used for
storage or if the goods must be returned.
Content
Please check that the content corresponds to your order and packing list.
Every shipment should include:
•Sensor w/ 10 m (33ft) cable
Optional parts for pHX / ORP Sensor:
•Slide rail mounting bracket for 28 mm Sensors P/N 11205264
•Flushing system 1 meter excl. solenoid valve P/N 11205612
Flushing system 2 meter, excl. solenoid valve P/N 11205903
•Solenoid valve 220V for flushing P/N 11705516A
Incoming hose ∅16mm (5/8”) , to sensor ∅6mm (1/4”)
Solenoid valve 110V for flushing P/N 11705916B
•Aluminum handrail mounting plate predrilled for BB2
and solenoid valves w/ u-bolts P/N 10305532
•1,5 m (5 ft) extension cable with pug-in connectiors. P/N 20805752
10 m (33 ft) extension cable with plug-in connectors. P/N 20805510
30 m (98 ft) extension cable with pug-in connectiors. P/N 20850727
•Connection box for two sensors to one BB2 control box P/N 11505748
with 1m (3 ft.) cable to connect to BB2
•Connection box for four sensors to one BB2 control box P/N 11505785
with 1m (3 ft.) cable to connect to BB2
•PH electrode, Teflon, excl. cable P/N 21850825
•ReX electrode, excl. cable P/N 21803401
•Cable for pH/ORP-electrode 1 meter P/N 20803393
•Cable for pH/ORP-electrode 2 meter P/N 20850717

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6. Installing the Sensor
The sensor is installed with the enclosed mounting brackets, which are screwed onto the
wall of the flume or tank (see figure 1). An optional adjustable slide rail holder is
available. The electrode should be placed deep enough so that it always stays in the
measuring media, even when the level varies (see figure 1). The measuring ability of the
electrode is influenced negatively if the column of liquid to be measured is too large.
For water, the column should not exceed 300 mm (12").
For applications where the level varies greatly, a mounting kit with a float ball should
be used. Take care to mount the mounting kit in such a manner that it is easily
accessible in conjunction with calibration.
It is best to place the cable to the mounting kit in conduit to protect the cable from
physical damage. Reserve a free section of the cable next to the sensor so that you can
remove it in conjunction with calibration.
The mounting sensor should be mounted in a vertical position. In some applications it
may be desirable to mount the mounting kit at a certain angle. The angle from the
horizontal plane should be greater than or equal to 45°.
Maximum water level
300 (12")
Figure 1: Installing the Mounting Kit in a Flume

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Connections
Connect the sensor to the BB2 central unit using the attached cable. If needed, the cable
can be extended using extension cables. Several sensors can be connected to one BB2
using Y-splitter or junction box. See “Technical description” for details.
Installation hints
•The electrode should be placed deep enough so that it always stays in the measuring
media
Starting Up
Connect the supply voltage. Remove the small plastic protector from the electrode
probe.
•If the electrode has been in the protector for an extended period of time,
salt crystals may need to be rinsed away with water.
•If the electrode has holes for refilling, the electrolyte inside the electrode
should be checked and refilled. The level should be at least 1 cm (1/2")
below the refilling hole. (NOTE! This does not apply to gel electrodes.)
•Place the electrode in a buffer of pH 7.00 for approx. 2 hours (does not
apply to Redox).
7. Removing the sensor
The sensor is removed in the following steps:
•Disconnect the sensor cable from the BB2 and the flushing hose from solenoid.
•Clean the sensor with a brush or clean cloth. Do not use a wire brush!
•Dismount the electrode.
•Mount the protective cap (or a small plastic bag) on the sensor cable connector.
•Blow compressed air through the flushing hose to get rid of the water in the hose
and the sensor.

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8. Mounting the electrode
In order to mount an electrode the sensor must be opened in both ends. At the cable end,
the electronics of the sensor is mounted to the black PVC-top. Care must be taken in
order not to damage the circuit board. Both ends are easiest opened by carefully turning
and pulling at the same time.
The electrode is mounted in the electrode holder by taking the enclosed nut, washer and
O-ring and threading them onto the electrode. Adjust the electrode position so that the
small ceramic part (marked 1 in figure 2) on the lower part of the electrode is in contact
with the measuring media. Then tighten the nut with your hand.
If you have an electrode, which does not have a hard-wired cable, the protective cover
on top of the electrode should be removed and the enclosed plug-in cable should be
used to connect the electrode and the electronics.
Feed the cable through the sensor tube, and mount the electrode holder in the tube. Be
careful not to damage the sealing.
Connect the cable to the electronics, and mount the electronics in the tube. It is easier to
get the cable in place if the tube is turned so the cable gets curled. Be careful not to
damage the sealing or the cable.
If the electrode cannot be immersed into the measuring media before it is put to use, the
electrode's small, plastic protective cover should be filled with a buffer solution of pH 7.
Figure 2: Mounting the electrode

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9. Cleaning
The sensor can be equipped with a flushing nozzle. The nozzle is used to direct the
cleaning liquid supplied through a ¼” hose that is mounted along the sensor housing to
flush the electrode. A solenoid valve that is wired to a relay in the BB2 control box
controls the air or liquid. Water is recommended for flushing in aeration basins.
Flushing must be activated in the “Settings” menu in the BB2 control box:
•Select the transmitter in the Main Menu by using the or buttons.
•Press ENTER for approximately five seconds to enter the Transmitter Menu.
•Use the arrows to select “Cleaning” and press ENTER.
•In the “Cleaning” submenu,
•If the sensor is to be cleaned as master, i.e. it has its own relay, then set the
“Cleaner” setting to “flush”, specify the cleaning interval in minutes, and the
flush time in seconds. If the sensor is to be cleaned as a slave, along with another
sensor, these parameters are set for the sensor being the master.
•If needed, specify the extra freeze time in seconds.
•If the sensor shall be cleaned as master, specify the relay to be used according to
the wiring inside the control box. For example, if the solenoid is wired to relay
#1, select “#1” for flushing. If the sensor is to be cleaned as a slave, specify
“Along #1” or “Along #2” depending on what relay the master sensor uses.
•For sensors configured as masters, “Next time” displays the next time flush will
be activated, pushing ENTER will set it to current time and those start cleaning.
NOTE! Pay attention to the requirements for protection against backflow, according to
the EN 1717 standard for drinking water devices. If possible, use plant reuse water or
effluent water for cleaning.
Mounting plate for cleaning solenoid valves
To provide an easy mounting of solenoid valves for the built-in flushing nozzles Cerlic
offers a predrilled Aluminum handrail mounting plate. The Mounting plate is fixed to
the rail using two u-bolts.
Mounting plate P/N 10305533 for one or two solenoids, outside US version P/N 11705516A
(11705516 B US Version) and a connection box P/N 11505748.

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10. Maintenance
pHX / ReX sensors are easy to maintain. An electrode maintenance schedule should be
kept, listing when it is removed and cleaned. When this is done, the electrode should be
checked against a known buffer solution. If the control value does not match, a re-
calibration should be made.
Use distilled water for cleaning.
Regularly check that the mounting kit does not get damp or wet inside during cleaning
and other activities. Also check that the electrode is correctly mounted in its holder to
avoid leaking.
Error messages
Window text
Problem
Solution
Unknown buffer The smart calibration does not
recognize the current buffer
from the signal of the electrode
•Use standard buffers 4.00,
7.00, and 10.00.
•Broken sensor, electronic
components, or cable
connection..
Same Buffer During calibration the pHX does
not perceive a difference of
buffers.
•Make sure that you use two
different buffers during
calibration.
•The electrode may be broken.
•The electronic components in
the sensor may be broken.
Broken Electrode
Lightning or static discharges during thunder storms may cause damage to the electrode,
and could also damage the signal amplifier. The electrode is the most exposed point
since it is in direct contact with the water and, consequently, the ground connection for
a discharge.
Physical damage to the electrode usually makes measuring impossible. Make sure that
neither electrode nor cable is damaged.
Incorrect Measurements
Problem
Solution
Dirty electrode
−
Clean with distilled water
Insufficient or poor reference solution
in the electrode
−
Refill/change reference solution (only
for refillable electrodes)
Change of "slope"due to age −Recalibration
- Re-activation (new reference
solution) only for refillable electrodes
Old electrode which gives slope <93%
−Change electrode

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11. Sensor display
By simultaneously pressing and ENTER you alter between BB2 main menu and the
sensor information display for the selected sensor. pHX / ReX has two information
pages, the first one shows in addition to the measured value, Max, Min, and average
values for the last 24 hours. The values are based on hour values which means they may
jump when a new hour starts and the oldest is skipped. The second information display
shows the date of the last calibration (pHX only) and the date the electrode was
changed.