palintest MICRO 500 User manual

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INSTRUMENTS
_____________________________________________________________________________________
MICRO 500
pH METER
OPERATING INSTRUCTIONS
PT 140 MICRO 500 pH METER
(pH/mV/Temp Meter)
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PALINTEST LTD, Palintest House, Team Valley, Gateshead, Tyne & Wear England NE11 0NS
Tel: [phone] Fax: [phone] E-Mail: [email protected]om
® INST.21

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TABLE OF CONTENTS
1 INTRODUCTION....................................................................... 3
1.1 Introducing the Micro 500 pH Meter .......................................... 3
2 GETTING STARTED................................................................. 4
2.1 Description of Keypad Functions............................................... 4
2.2 Description of LCD Annunciators............................................... 4
2.3 Inserting & Removing the Rubber Boot ..................................... 5
2.4 Inserting New Batteries ............................................................. 5
2.5 Battery Replacement................................................................. 6
2.6 Connecting the Electrode and Temperature Sensor.................. 6
2.7 Switching the Meter On ............................................................. 6
3 CALIBRATION.......................................................................... 7
3.1 pH Calibration............................................................................ 7
3.2 Temperature Calibration............................................................ 9
3.2.1 With Temperature Probe for Preselected Curve....................... 9
3.2.2 With Temperature Probe with Curve Selection........................ 10
3.2.3 Without Temperature Probe (no ATC) ................................... 11
3.3 Millivolt (mV) Calibration.......................................................... 12
4 MEASUREMENT .................................................................... 13
4.1 Taking Measurements............................................................. 13
4.2 Holding a Reading................................................................... 14
4.3 Releasing a Held Reading....................................................... 14
5 ELECTRODE CARE AND MAINTENANCE ............................ 14
6 TROUBLESHOOTING ............................................................ 15
7 SPECIFICATIONS .................................................................. 16
8 ACCESSORIES ...................................................................... 17
9 WARRANTY............................................................................ 17
APPENDIX (Electrodes and Electrode Care) ...................... 18

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1 INTRODUCTION
1.1 Introducing the Micro 500 Series
Thank you for purchasing the Palintest Micro 500 pH
meter. This microprocessor-based hand-held meter is
easy to use and has a large custom LCD (Liquid Crystal
Display) for clear and easy reading.
The Micro 500 pH meter allows pH, temperature (°C) and
millivolt measurement. Millivolt measurement (mV) can be
used for taking Redox or ORP (Oxidation or Reduction
Potential) readings with ORP electrodes.
This instruction manual is organised for quick reference
with step-by-step procedures that give you thorough
review of the various features and meter operations.
Included with your meter are a pH electrode, temperature
sensor, rubber boot, 4 x alkaline ‘AAA’ batteries, an
instruction manual and a warranty card. Please refer to the
section on ‘Accessories’ for more information on pH
buffers and other accessories.

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2 GETTING STARTED
2.1 Description of Keypad Functions
The Palintest Micro 500 pH meter has four keys on its
splash-proof keypad. These include ON/OFF, HOLD/
ENTER, CAL and MODE/INC keys.
ON/OFF: Powers the meter on and turns it off. Meter
directly enters measurement mode when you
switch it on.
MODE: Selects measurement mode for pH, mV and
temperature.
CAL: Allows calibration for pH, mV or Temperature, or to
abort calibration without confirming any set value.
INC: Allows you to increment values during calibration
mode.
HOLD: Freezes the measured reading for easy viewing.
ENTER: Confirms calibration value.
2.2 Description of LCD Annunciators
The meter has a large custom LCD that consists of 3½-
digit segments and operation annunciators for pH, mV or
°C (temperature). Other annunciators include ‘HO’ (when
the HOLD function is activated) and ‘LO’ (low battery
condition) :
HO pH
o
C
LO mV

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2.3 Inserting & Removing the Rubber Boot
1 To remove meter from rubber boot, push out from the
bottom edges of meter until it is completely out of boot.
Ensure that the cables of pH electrode or temperature
probe are not connected.
2 To insert meter into rubber boot, slide in from the top of
meter before pushing the bottom edges of meter down to
set it into position. Lift up the stand at the back of meter
for bench top applications if necessary :
2.4 Inserting New Batteries
The battery compartment is found at the back of instrument.
To open the battery compartment, push in the direction of
arrow and lift up the cover. Note the polarity of battery
before inserting into position. After replacement, place
cover back and press down until it locks tight :

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2.5 Battery Replacement
A ‘LO’ annunciator in the LCD alerts you when battery
power is running low. Replace batteries as soon as
possible after ‘LO’ symbol appears :
Caution: Power off the meter when changing battery.
2.6 Connecting the Electrode and Temperature Sensor
To connect electrode into meter, align the connector slots
with the posts of meter’s socket and rotate connector
clockwise until it locks. Do not force when connecting. To
remove, simply rotate the connector in anti-clockwise
direction until it unlocks, and slide the connector off the
socket.
Insert the mini phono jack of temperature sensor into the
socket on the meter. Unplug the phono jack when not in use
or to measure pH without any temperature compensation.
2.7 Switching the Meter On
1 Press ON/OFF key to power up your meter. All LCD
segments display momentarily as the meter performs a
self-diagnostic test, per shown in section 2.2. The LCD
then switches into pH measurement mode.
pH
7.00
LO

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2 Press MODE key to choose your desired mode of
measurement with its corresponding annunciator displays in
the LCD. For temperature mode, the measured reading can
be 25.0°C (factory default) or the last calibrated temperature
value if there is no temperature probe, or the current
measured value if a temperature probe is connected.
3 The LCD displays ‘Ur’ if the meter reading exceeds the
maximum or ‘Or’ if under minimum possible measurement
range (refer to section on Specifications) :
3 CALIBRATION
3.1 pH Calibration
The meter is capable of up to three-point calibration with
standard pH buffer values at pH 4.01, 7.00 and 10.01 to
ensure accuracy across the entire range of the meter. It
also allows offset adjustment in mV and Temperature
modes. All new calibration values will automatically
override existing data.
It is recommended that you perform at least two-point
calibration at room temperature using standard buffers,
starting with pH 7.00 followed by either pH 4.01 or 10.01.
For a one-point calibration, calibration should be performed
with a pH buffer value closest to expected sample value
being measured. Otherwise calibrating at pH 7.00 is
advisable.
Ensure that you use fresh pH buffer solutions during
calibration. Do not re-use buffer solutions as they may be
contaminated and affect the calibration and accuracy of
measurements. Palintest Buffer Packs provide single-use
buffer solutions from easy to use buffer tablets (see
Accessories Section).
ur Or

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Before use, remove the plastic protective cap of pH electrode
and condition the glass bulb by soaking it in tap water for 1 -
2 hours. This hydrates the glass bulb if electrode is too dry or
has not been used for a long period of time.
Always rinse the probes with tap water or rinse solution
before and after each calibration/sample measurement to
avoid cross-contamination. For details please refer to
section on Probe Care and Maintenance.
1 Take a sample tube containing the pH 7 solution. Power
on the meter, and the meter will automatically enter pH
measurement mode.
2 Dip both electrode and temperature sensor into the buffer
solution. Swirl gently and wait for reading to stabilise
(approx 30 seconds).
3 Press CAL key to enter calibration mode. A ‘CA’ displays
momentarily and the display shows the current uncalibrated
reading flashing while in the calibration mode :
Allow reading to stabilise. The meter automatically
recognises pH 4.01, 7.00 or 10.01 buffers. Press ENTER
key once to confirm calibration, the LCD displays ‘CO’
momentarily once calibration is confirmed. The meter exits
calibration mode and returns to measurement mode :
Alternatively you can press CAL key to abort or exit
calibration mode, without accepting new value while you
are in calibration mode.
ca 7.00
pH
co 7.00
pH

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For 2 or 3-point calibration, repeat with pH buffers 4.01
and /or 10.01 for best accuracy.
Important: This meter has automatic buffer recognition
which identifies the correct pH buffer values during
calibration. If buffers other than pH 4.01, 7.00 or 10.01 are
used, or the electrode has worn out, the LCD will flash
‘Er1’. For pH 7, the tolerance is ± 1.50 pH, while for both
pH 4 and pH 10 is ± 1.00 pH :
3.2 Temperature Calibration
3.2.1 With Temperature Probe For Preselected Curve
The temperature sensor included with your meter is
factory-calibrated. Over time, the temperature calibration
may drift and require recalibration. If you replace the probe
you should calibrate temperature probe prior to pH or mV
calibration.
1 Connect your temperature probe to the meter. Press MODE
key to enter Temperature mode until ‘°C’ annunciator appears
in the LCD.
2 Compare the displayed value to a NIST certified
thermometer or other thermometer known to be accurate.
For best accuracy, place probe and thermometer in a
constant temperature bath.
3 Press CAL key to enter temperature calibration mode. The
LCD shows ‘CA’ momentarily and the displayed reading
flashes :
Er1
ca
o
C
26.5

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5 Press INC key until the displays shows the correct
temperature. The INC key will scroll to the maximum
allowable value and then loop back to the minimum
allowable value adjustment (maximum adjustment is ± 5°C
from factory default).
6 Press ENTER key to confirm calibration. The LCD displays
‘CO’ momentarily, and the meter reverts to measurement
mode :
3.2.2 With Temperature Probe (with Curve Selection)
In the event the temperature probe has drifted too far from
its original characteristic due to age and use or if the probe
is being replaced, it may be a good idea to match the
probe to the best curve. There are 3 curves programmed
in the unit. To choose the curve, proceed as follows :-
1 Connect your temperature probe to the meter. Dip the
probe in a constant temperature bath or a liquid whose
temperature can be checked with a thermometer known to
be accurate. For best accuracy, place the probe and
thermometer in a constant temperature bath.
2 Make sure that the meter is in the pH measurement mode.
Press CAL key and the pH value flashes to indicate that
you are in the CAL mode.
3 Press MODE key. The display will show the temperature
of measured liquid.
4 Press MODE key. Each press will take you through one
curve. Choose the curve which gives you a reading closest
to the actual value (of the bath or thermometer).
co
o
C
25.0