pH Transmitter
IXIAN TM
IXIAN TM class
pH Transmitter
V 2.6
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Features
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4 – 20mA output
Full range pH reading from .001 to 14.000
Accurate pH readings down to the thousands place (+/- 0.002)
Calibrate remotely through a PLC or directly on the board
On board pH display
Din rail mount
Self test on startup
Automatic fault detection
Wide operating voltage (14 VDC to 36VDC)
PT100 / PT1000 temperature probe compatible
Works with any two lead pH probe
Fully electrically isolated for noise immunity
IXIAN
(ick-see-an) “supreme in machine culture,” –Dune
TM
Patent pending
Description
The IXIAN™ class pH Transmitter is our premier technology designed exclusively
for industrial processes. Operation, calibration and communication is both fast
and easy. The IXIAN ™ class pH Transmitter is ready for 24 hour/ 365 day
operation with no down time. From cash crop growing to chemical manufacturing,
the IXIAN ™ class pH Transmitter will ensure that your process yields
profitable results.
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pH Transmitter
IXIAN TM
Contents
Hardware ...........................................
Mounting ...........................................
Power connection ..............................
pH connection ....................................
Temperature connection ....................
Remotely calibrating through a PLC ...
Calibration theory ..............................
Calibration .........................................
4–20mA calibration .............................
Temperature compensation ...............
Factory reset ..................................
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pH Transmitter
IXIAN TM
Keyed power connector 14 – 36V
Power isolator
4-20 pH to PLC connection
Voltage attenuator
PLC calibration
and fault detection node
Data isolator
4-20 current loop generator
Power on indicator (BLUE)
Quick calibration buttons
7 segment pH display
pH interpreter engine
under EMI shield
pH probe connecter
PT100 / PT1000 temperature
probe connecter with auto detect
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pH Transmitter
IXIAN TM
35 mm DIN Rail mount
DIN rail release notch
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pH Transmitter
IXIAN TM
63.02mm
(2.48”)
108.57mm
(4.27”)
66.3mm
(2.6”)
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pH Transmitter
IXIAN TM
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pH Transmitter
IXIAN TM
Mounting
The IXIAN™ class pH Transmitter is specifically
designed to be mounted to 35mm Din rail.
Power connection
Any DC voltage from 14V to 36V can be used to power the IXIAN™ class pH Transmitter.
The power connector is keyed and different from all other connectors.
Power
consumption table
mA
VDC
56
14
34
24
24
36
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pH Transmitter
IXIAN TM
pH connection
Any off the shelf two wire pH probe can be used with the IXIAN™ class pH Transmitter.
Connecting the pH probe in reverse will not damage the probe
however, the readings will be incorrect.
Temperature connection
A PT100 or PT1000 temperature probe is connected here.
or
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Either method of wiring will produce the same result.
There is no polarity
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pH Transmitter
IXIAN TM
Remotely calibrating through a PLC
Input connections
Using the PLC calibration node is optional. Leaving
it d i s c o n n e c te d w i l l h a v e n o e f f e c t o n device’s
operation.
“4”, “7”, “10”
Using the three input connections marked “4”, “7”, “10” it is possible to use a PLC to
fully calibrate the IXIAN™ class pH Transmitter. This is particularly beneficial when using
a PLC touch screen.
Sending an output signal from the PLC to the pH Transmitters 4, 7, or 10 input
connection will calibrate the device.
See page 11 for detailed instructions.
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pH Transmitter
IXIAN TM
Output connections
Normal operation
(24v typical)
Fault
0 Volts
“F”
The connection marked “F” is the fault detect line. During normal operation the fault line
will output a voltage equal to the voltage used to power the device. If the pH Transmitter
detects a problem the fault line will drop to 0 volts.
Example
The IXIAN™ pH Transmitter is powered with 24V the “F” line will output 24V during normal
operation.
Events that will trigger the fault line to go to 0 volts
• pH probe reporting a pH of less than 0 or greater then 14
• disconnected temperature probe
• calibration in process
• loss of power
4–20 mA pH transmission
The pH that is visible on the seven segment LED screen is also simultaneously transmitted
through the 4-20mA current loop. Connect the 4-20mA Data Output to the PLC.
PLC ADC Resolution
pH to 4-20mA equation
pH
0
1
2
3
4
5
6
7
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mA
4.0000
5.1428
6.2857
7.4285
8.5714
9.7142
10.8574
12.0000
pH
8
9
10
11
12
13
14
mA
13.1428
14.2857
15.4285
16.5714
17.7142
18.8571
20.0000
10 BIT = 0.015 pH units
16 BIT= 0.003 pH units
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pH Transmitter
IXIAN TM
Calibration theory
The Atlas Scientific IXIAN™ class pH Transmitter has a flexible calibration protocol,
allowing for single point, two point, or three point calibration.
The calibration values are
4.0, 7.0, 10.0
The first calibration point must be a pH 7.0
Calibrating to pH 7.0 will reset the stored calibration. If two, or three
point calibration has been done in the past it must now be redone.
The other two calibration points are pH 4.0 and pH 10.0 There is no correct order
of calibration for these two points. Recalibrating these two points will not have any
effect on the other stored calibration points. Calibration to pH 4.0 and pH 10.0 can
be done at any time.
14
pH 4.0
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pH 7.0
pH 10.0
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pH Transmitter
IXIAN TM
No calibration
One point calibration
pH 7.0
Two point calibration will provide high accuracy between pH 7.0 and
the second point calibrated against, such as a pH 4.0.
pH 4.0
pH 7.0
Three point calibration will provide high accuracy over the full pH range.
3 point calibration at pH 4.0, 7.0 and 10.0 should be considered
the standard.
14
pH 4.0
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pH 7.0
pH 10.0
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pH Transmitter
IXIAN TM
Calibration
Calibration can be done on the board itself, or through the PLC using the input lines
marked “4”, “7” and “10”.
If a full calibration is being done always
start with pH 7.0.
Using the three input connections marked “4”, “7”, “10” it is possible to use a PLC to
fully control the IXIAN™ class pH Transmitter. This is particularly beneficial when using a
touch screen PLC.
Setting a PLCs output to 200ms or more will trigger a calibration event.
Timer 1
CAL 4
button press
T1
200ms
CAL 4
Transmitter
T1
( OUT )
Calibrate
4.0
7.0
10.0
System
working
Red
Tower light
( OUT )
A calibration event will only trigger if the
cosponsoring input pin has been held
high for 200ms. Holding the line for
more then 200ms will have no effect.
Calibration through the buttons
on the IXIAN™ class pH Transmitter
Press and hold the button marked “7.0” for 1.5 seconds to calibrate to a pH of 7.0.
The display will flash: CAL 7.0
The display will flash: donE
Repeat this process to calibrate for pH 4.0 and pH 10.0.
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pH Transmitter
IXIAN TM
4–20mA calibration
To ensure that the PLC is receiving the most accurate 4-20mA signal the current output
from the IXIAN™ pH Transmitter can be adjusted. The 4mA signal and the 20mA signal
can both be adjusted independently.
To enter 4-20 calibration mode press and hold the RED and BLUE buttons simultaneously
for 1.5 seconds.
4–20mA H (H=High)
The pH Transmitter will now output exactly 20mA. Your PLC should show a pH of 14. Use
the buttons to adjust the 20mA output so the pH moves to 13.99, then move it back up,
so it is just hits pH 14.
To calibrate the 20mA signal
When finished press
the RED button
The 20 mA offset will be permanently stored in memory.
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pH Transmitter
IXIAN TM
4–20mA L (L=Low)
The pH Transmitter will now output exactly 4mA. Your PLC should show a pH of 0.
Use the buttons to adjust the 4mA output so the pH moves to -0.1, then move it back
up, so it is just hits pH 0.
To calibrate the 4mA signal
When finished press
the RED button
When finished the 4 mA offset will be permanently stored in memory.
Temperature compensation
The IXIAN™ pH Transmitter will automatically perform temperature compensation when
a PT100, or PT1000 temperature probe is connected to the device. The pH Transmitter
will use 25˚C as the default temperature if a temperature probe is not connected. The
device will continue to operate normally however, the fault line will be low, indicating the
system cannot perform temperature compensation.
To view the temperature that the IXIAN™ pH Transmitter is reading from the attached
PT100, or PT1000 temperature probe, press the red and orange buttons simultaneously.
The display will now show the temperature. It will continue to display the temperature for
10 seconds, or until the RED and ORANGE buttons are pressed again. Atlas-Scientific.com
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pH Transmitter
IXIAN TM
Factory reset
The IXIAN™ pH Transmitter can be reset to its default settings. To issue a factory reset,
press and hold the ORANGE and BLUE buttons for three seconds.
The display will flash: rEsEt
Press and hold the ORANGE and BLUE buttons again to confirm the factory reset.
To cancel a factory reset, press the RED button.
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pH Transmitter
IXIAN TM
TM