IQ Scientific Instruments IQ160 User manual

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Waterproof Handheld Meters
IQ160 pH Meter
IQ170 pH/mV/Temperature/Conductivity
TDS/Salinity Meter
IQ340 Conductivity Meter
IQ350 Conductivity/TDS/Salinity Meter

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Conductivity Calibration
Quick Start Guide
Model IQ170, IQ340 and IQ350
Connect probe to meter.
Put probe in first cali-
brating solution.
Press ON/OFF to turn
on meter.
If necessary, press
CON until COND icon
is seen on the display.
Press CAL.The conductivity value
will flash. Press the ▲
or ▼key until the
display matches the
calibrating solution.
Press ENTER
Rinse probe in
deionized water
and place in
sample.

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pH Calibration
Quick Start Guide
Model IQ160 and IQ170
Connect probe to me-
ter.
Put probe in first
calibrating buffer.
Press ON/OFF to
turn on meter.
If necessary, press
pH until pH icon is
seen on the display.
Press CAL.If necessary, press
the ▲or ▼key
until display
matches first buffer
value.
Press ENTER and
wait until the large
number display stops
flashing.
When complete,
meter will display
the next stored
buffer value. CAL 2
will be displayed
Rinse probe in deion-
ized water and place
in second calibrating
buffer.
If necessary, press
the ▲or ▼key
until display
matches second
buffer value.
Press ENTER and
wait until the large
number display stops
flashing.
Rinse probe in
deionized water and
place in sample.
1

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INTRODUCTION
IMPORTANT NOTICE
SAFETY PRECAUTIONS
IF THE METER IS USED IN A MANNER OTHER THAN AS DESCRIBED,
THE SAFETY AND
PERFORMANCE OF THE METER CAN BE IMPAIRED.
IF THE SEAL ON THE BACK OF THE METER IS TAMPERED WITH, THE
WARRANTY IS
IMMEDIATELY VOIDED.
The IQ160 pH meter and IQ170 multi-parameter meter accept both traditional
style glass sensor electrodes with BNC connectors and non-glass pH probes
with ISFET (Ion Sensitive Field Effect Transistor) silicon chip sensors. The
IQ170 multi-parameter meter, and the IQ340 and IQ350 meters accept
conductivity probes.
Throughout this manual, non-glass pH probes with silicon chip sensors will be
referred to as “ISFET” probes. Glass sensor pH electrodes will be referred to
as “BNC” probes. The pH meters have a standard BNC connector for
attachment of glass sensor pH electrodes and a separate connector for ISFET
probes.
The pH meters are designed to use only one pH electrode (either a BNC pH
probe or an ISFET pH probe) at a time. The meter automatically identifies
which type of electrode is attached when the meter is turned on. If both
ISFET and BNC probes are attached at the same time, errors may occur.
Always turn off the meter when changing electrodes. NOTE: Both pH and
conductivity probes can be attached simultaneously to the model IQ170.
ESTIMATED LIFE OF AN ISFET SENSOR pH PROBE
Depending upon the application, the expected life of an ISFET probe is
approximately 18 months. The reference electrode contains a KCl gel, which
becomes increasingly diluted with usage and time. The reference is sealed
and is not refillable. When it becomes difficult to calibrate (pH buffer value
does not stop flashing during calibration or takes an excessively long time to
stop flashing), the probe should be replaced. A probe that is dirty,
miscalibrated, or has reached the end of its useful life will give an error
message E06 on the meter display. Your ISFET probe is warranted to be free
from manufacturing defects for six (6) months from the date of
purchase.

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Table of Contents
Quick Start Guide — Conductivity Calibration. . . . . . . . . . . . . . . . . . . . . i
Quick Start Guide — pH Calibration. . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Section 1: Techniques and Tips for Best Performance. . . . . . . . . . . . . . . 4
Section 2: Specifications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Section 3: Instrument Features. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Section 4: Keypad Functions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Section 5: Probes and Connections. . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Section 6: Probe Cleaning. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Section 7: pH Calibration (Model IQ160 and IQ170 Only). . . . . . . . . . . . . 22
Section 8: Conductivity and TDS Calibration
(Model IQ170, IQ340, and IQ350 only). . . . . . . . . . . . . . . . . . . . . . . . .
26
Section 9: Setup Functions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
pH Resolution. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
2 or 3 Point pH Calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Stabilization Lock. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
Temperature Display in oC or oF. . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Manual Temperature Compensation for Glass Electrodes. . . . . . . . . . . 35
Conductivity Temperature Compensation Coefficient. . . . . . . . . . . . . . 37
Reviewing Conductivity and TDS Calibration Points. . . . . . . . . . . . . . . 38
Conductivity Temperature Normalization . . . . . . . . . . . . . . . . . . . . . 40
TDS Conversion Factor. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
Setting TDS Units . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
Setting Salinity Units. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
Sound. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
Clear Glass pH, Conductivity, and TDS Calibration Points. . . . . . . . . . . 48
Section 10: Troubleshooting Guide. . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
Section 11: Error Codes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
Conductivity Probe Cell Constants. . . . . . . . . . . . . . . . . . . . . . . . . . . 45
Meter Automatic Shutoff Time. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47

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SECTION 1:
Techniques and Tips for Best Performance
DO
DO: (ISFET non-glass probe ONLY) Soak the probe in pH 7.00 buffer for
at least five minutes if the probe is new or has been stored dry for an ex-
tended period. This will hydrate the sensor and dissolve any reference mate-
rial, which may have crystallized on the sensor surface. NOTE: If a probe is
in regular use, pre-soaking is not necessary
DO: (ISFET non-glass probe ONLY) Clean the probe regularly with a
toothbrush and mild detergent.
DO: (ISFET non-glass probe ONLY) STORE THE PROBE DRY with the black
protective cap covering the probe tip. No electrode storage solution is re-
quired.
DO: (BNC probe ONLY) Store the probe in electrode storage solution.
DO: Always begin each measuring session with a two-point calibration. Up-
date often with one-point, two-point or three point calibrations.
DO: Use fresh buffers and deionized rinse solution.
DO: Use buffer solutions with pH values no greater than three pH units apart.
Buffers should bracket the anticipated values of the samples to be measured.
DO: Use deionized water to rinse residual buffer and sample solutions from
the probe after calibration and measurement.
DO: Calibrate at the same temperature as the sample solution. Although the
meter has automatic temperature compensation, best results will be achieved
if the calibration buffers and sample are the same temperature.
DO: Keep the connectors clean and dry. Dirty or damp connectors can cause
unstable readings.

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DO NOT
DO NOT: change pH probe types (switch between BNC and ISFET probes)
while the meter is turned on. Always turn off the meter before changing
probes.
DO NOT: simultaneously use ISFET and BNC probes. Only have one type of
probe attached to the pH meter at a time. NOTE: Both pH and conductivity
probes can be simultaneously attached to the IQ170 multi-parameter meter.
DO NOT: store an ISFET probe in solution or use for long-term pH measuring
applications. Unlike BNC electrodes, stainless steel ISFET electrodes should
be stored dry. Extended immersion will shorten the life of the probe.
DO NOT: leave an ISFET probe uncapped for long periods of time. Always
place the protective cap over the probe tip when finished measuring.
DO NOT: allow oil, fat, food particles, starch, protein, or other materials to
remain on the probe tip after use.
DO NOT: use a sharp metal object (needle, pin, etc.) to clean the sensor
surface.
DO NOT: take readings in direct sunlight. Direct sunlight may cause unsta-
ble readings or difficulty in calibration. Call IQ Scientific Instruments or your
Authorized Dealer for optional light shields.
DO NOT: use the probe in an environment that will damage the sensor, such
as hydrofluoric acid or abrasive samples.
DO NOT: use the probe in environments that will damage the epoxy materi-
als used in the probe tip. Avoid acetone, toluene, methylene chloride, xylene,
and other strong organic solvents.
DO NOT: use in environments with static electricity. Electrostatic discharge
may permanently damage the probe.
DO NOT: expose the ISFET probe to repeated temperature extremes (60 oC
or higher). Do not use the probe for applications that require the probe to
cycle between hot and room temperature samples.
DO NOT: put any other active measurement devices in buffers or samples
while measuring pH or conductivity. Even if another device is not actually
turned on, AC power interference can still occur.

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SECTION 2: Specifications
Table 1: Specifications
pH mV Temperature Conductivity TDS Salinity Range 0.00 – 14.00 Autoranging
±199.9 mV
±1999 mV
-5.0 to 105.0 °C 20.0 to 199.9 °F
Autoranging
0.00 to 19.99 µS 20.0 to 199.9 µS
200 to 1999 µS
2.00 to 19.99 mS 20.0 to 199.9 mS
Autoranging
0.00-9.99 ppm 10.0-99.9 ppm 100-999 ppm 1.00-9.99 ppt 10.0-99.9 ppt 100-200 ppt Will also display in mg/L 0.00-199.9 mg/l 200-1999 mg/l 2.00-19.99 g/l 20.0-50 g/l
0-42 ppt
Resolution 0.01 pH Autoranging
0.1 and 1
0.1 °C 0.1 °F
0.01 µS
0.1 µS
1 µS
0.01 mS
0.1 mS
0.01 ppm 0.1 ppm 1 ppm 0.01 ppt 0.1 ppt 1 pt 0.1 mg/l 1 mg/l 0.01 g/l 0.1 g/l
0.1 ppt
Accuracy ±0.01 pH ±0.1 mV ±0.5 °C ± 1% full scale or ±1
digit
± 1% full scale or ±1 digit +/- 0.1 ppt
(-2 to 35 °C)
Calibration Up to three points
With automatic buffer recognition 1.68,4.01, 6.86, 7.00, 9.18, 10.01, 12.45
None Offset in 0.1 °C
increments
Up to five points Up to five points None (derived from
conductivity)

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Sound:
Sounds will occur as follows:
• Three short beeps any time measurement stability is
reached during calibration mode, regardless of the
Stabilization Lock setting.
• Three short beeps when stabilization is reached when
in Stabilization Lock ON mode. The READY icon will
illuminate. (NO beep if Stabilization Lock is in the OFF
mode)
• Two long beeps if an error condition occurs. An error
code will be displayed.
• Audible click on key tap.
Automatic Ranging of mV Display
From -199.9mV to +199.9mV the meter will display 0.1
resolution. From 200mV to 1999mV the meter will display 1
mV resolution.
Automatic Ranging of Conductivity, TDS and Salinity
values.
Auto ranges between the five display ranges.
Automatic Detection of Cell Constant. The meter will
automatically detect the cell constant of a conductivity
electrode.
Auto Power off: Will automatically power off 20 minutes
after last key press.
LED Display Light:
LED light goes on when the light button is pressed. Light stays
on for 2 minutes after the last keystroke.
Conversion factor for TDS: User adjustable.

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Temperature Compensation:
Glass pH Temperature Compensation
If the meter is in the glass pH mode and a temperature
probe is plugged in to the 3.5mm phono jack, the
meter defaults to Automatic Temperature
Compensation (ATC). If no temperature probe is
detected it defaults to Manual Temperature
Compensation at 25 °C.
ISFET pH Temperature Compensation
ISFET pH is always automatically temperature
compensated using the thermistor built-in to the probe.
Conductivity Temperature Compensation
The internal temperature sensor in the conductivity
probe is used for conductivity temperature
compensation. The Conductivity automatic temperature
compensation coefficient is user selectable. Default is
2% per degree C.
NOTE ON pH ATC: Automatic Temperature Compensation
(ATC) for pH only occurs when using an ISFET pH probe (built-
in temperature sensor) or when a BNC pH electrode is used
with the separate temperature plug attached. After calibration
is complete and the meter is in the pH mode, the pH values
displayed will be temperature compensated. If no
temperature plug is attached when using a BNC electrode,