JENCO 6230M User manual

OPERATION MANUAL
JENCO
MODEL 6230M/6230N/6231M/6231N
MICROCOMPUTER BASED
pH/mV/TEMP
PORTABLE METER
JENCOELECTRONICS, LTD.
MANUFACTURER OF PRECISION INSTRUMENTS

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Model 6230M 6230N 6231M 6231N
Storage Yes No Yes No
RS-232C Yes Yes No No
NOTES: 1. RS-232C interface operation is for 6230M and 6230N only.
2.The saving, recalling and erasing data functions are for 6230M and
6231M only.
3. RECALL mode and ERASE mode are for 6230M and 6231M only..

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INITIAL INSPECTION
Carefully unpack the instrument and accessories. Inspect for damages made in
shipment. If any damage is found, NOTIFY YOUR JENCO REPRESENTATIVE
IMMEDIATELY. All packing materials should be saved until satisfactory operation
is confirmed.
GENERAL INTRODUCTION
The model 6230M, 6230N, 6231M or 6231N is a precise instrument for the
measurement of pH, mV, and temperature. A built-in microcomputer is used to
store, calculate, and compensate for all the relevant parameters relating to pH
determinations. These include temperature characteristics of the pH electrode, buffer
solutions and electrode slope deviations.
This instrument is made with a watertight case, which makes it splash resistant. The
mechanical touch keys are highly reliable with tactile and audio feedback. This meter
can be operated either with 6 AAA batteries or with an AC adaptor. Re-calibration is
not required when power is restored again. The instrument also displays a "LOBAT"
message when the batteries are in need of replacement.
The meter has a large LCD that displays the pH (mV) and temperature values
simultaneously along with the user prompting features and mode indicators. The
instrument prompts the user through the calibration and measurement procedures.
An AUTOLOCK feature is provided for both pH and mV measurements. This
enables the instrument to automatically sense the end point and “lock” the display to
indicate the end point value of a measurement. The meter can also be used in
non-AUTOLOCK mode.
The AUTOLOCK and the user prompting features help eliminate virtually all human
factors in the determination of pH and mV values, thus resulting in precise, repeatable
and error free measurements.
The meter can use pH electrode, ORP electrode and ATC (Automatic Temperature
Compensation) probe. One-point, 2-point or 3-point pH calibration can be used for
this meter and user should select one from them.
The meter is also equipped with a non-volatile memory allowing the user to store 40
different sets of readings. This unit will assign a site number for each set of readings,
so the user can review the data easily. (See Note 2)
Optional RS-232C can track all displayed values and interface the meter with
recorders, printers, computers, etc. (See Note 1)

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Other features include, low power consumption, percentage of power supply display,
electrode offset recognition, electrode slope recognition, built-in buffer coefficients,
automatic or manual temperature compensation, auto-saving pH calibration values,
and high 50/60 Hz AC noise rejection. This meter is USER FRIENDLY, for field,
industrial and laboratory applications.
SPLASH PROOF
The meter is splash resistant with a watertight case. The instrument should not be
operated under water since the pH electrode is not waterproof. The splash proof
feature is to prevent permanent damage to the instrument when accidentally splashed
with non-corrosive solutions. Take the following measures immediately in the event
that the instrument is dampened in any kind of solution:
1. Rinse the instrument thoroughly with distilled water. The connectors should be
sprayed with a jet stream of water to remove all contamination that might create
electrical leakage potential paths. This leakage path may reduce the impedance of
the instrument and create polarization current between the pH and reference cells
of the electrode.
2. Rinse the electrode and spray its connector in the same manner.
3. Wait for the instrument and probe to dry completely before resuming operation.
4. Replace the pH electrode if satisfactory operation is not resumed.
1. pH / ORP BNC CONNECTOR
2. REF. ELECTRODE INPUT CONNECTOR
3. ATC INPUT CONNECTOR
4. AC ADAPTOR INPUT CONNECTOR
5. ELECTRODE HOLDER
6. RS-232C CONNECTOR FIGURE 1 TOP VIEW

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CHANGING THE BATTERIES
When the LOBAT indicator is flashing, the user should check that whether the
external AC adaptor is connected to the meter reliably, and if only internal batteries is
used, the user should change the batteries. If the voltage of power supply is too low,
the meter will display “Sht” and then shut down automatically.
1. Position the meter so that the left side of the meter is facing up. (Refer to Figure
2) With a coin, inset it in the closure slot on the side labeled A. With the coin
tilted, thrust it upward to open the battery compartment and lift the cover up.
2. Insert the batteries and ensure polarities are correct.
A. SIDE CLOSURE SLOT
B. COVER
C. 6 AAA BATTERIES
FIGURE 2 REAR VIEW (BATTERY COMPARTMENT)
TURN ON/OFF INSTRUMENT
Once the batteries are installed correctly and/or an AC adaptor is connected reliably,
you can press ON/OFF key to turn on or turn off the unit. After the unit is turned on,
it will display all segments of LCD for a few seconds then the buffer set will be
shown. After a while the percentage of power supply will be measured and displayed,
then the unit will go to the last mode that has been saved.
When the unit is not in use, press the ON/OFF key to turn off the unit for saving
battery life. Unplugging the AC adaptor from the unit or from the AC line does
not turn off the unit. It would automatically switch to the internal batteries.
When turning off, the last display mode will be auto-saved, except during RECALL
and ERASE modes where it will default to pH-AUTOLOCK mode. Calibration data
and the 40 different site readings are saved in non-volatile memory, and will be intact
even if the user turns off the unit.

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THE KEYPAD (See Notes 2 and 3)
1. ON/OFF key:
The ON/OFF key turns the unit ON or OFF. The pH calibration values will not
be erased when the unit is turned off.
2. MODE key:
2.1. During normal operation, the MODE key will change the display mode
sequentially to pH-AUTOLOCK,mV-AUTOLOCK,pH, mV, RECALL
and ERASE. The calibration values will not be affected by changing the
display modes.
2.2. In pH calibration mode, the MODE key will exit the current calibration and
go to the measurement.
3. STAND and SLOPE keys:
3.1 The STAND and SLOPE keys are used for pH calibration of the instrument.
3.2 Press and hold the STAND key while turning on the power to change the
buffer set.
4. △(UP) and ▽(DOWN) keys:
4.1 The △and ▽keys are used to manually enter the temperature value in
manual (MAN) mode. These keys are inoperative when operating in ATC
mode.
4.2 In RECALL mode, the △and ▽keys will adjust the site number .
5. MEASURE key:
5.1 The MEASURE key is used to bring the instrument out of the
AUTOLOCK condition when operating in the pH-AUTOLOCK or
mV-AUTOLOCK mode.
5.2 During pH-AUTOLOCK,mV-AUTOLOCK,pH,or mV mode, pressing
and holding the MEASURE key for about 2 seconds will save all the
readings in the next available site number.
5.3 During RECALL mode, pressing the MEASURE key will display the
saved pH value and temperature value on the current site. Then pressing it
again will display the mV value and temperature value on the same site.
Press the MEASURE key one more time will go to the pH value and
temperature value.
6. CLEAR key:
During pH-AUTOLOCK and pH mode, the CLEAR key is used to clear all pH
calibration values stored in the internal memory and set them to default (ideal)
values. Under normal conditions, it will not be activated unless press and hold
this key for about 2 seconds. By doing this, the unit is ready for measurements
with STAND and SLOPE off and need not to be calibrated.

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7. MEASURE and ▽keys:
Pressing and holding this combination during ERASE mode for about 5 seconds
will erase ALL data saved in the non-volatile memory. All 40 sites will be
erased completely. Do not use this function until all recorded data has been
reviewed or transcribed or downloaded.
THE LCD AND KEYPAD DESCRIPTION
1. STAND & SLOPE: Calibration indicators.
2. Main display: for pH and mV values.
3. Secondary display: for temperature value and site number.
4. AUTOLOCK : AUTOLOCK mode indicator.
WAIT: Displays while the unit waits for a stable reading or end port sensing.
5. All eight control keypads.
6. ATC & MAN: “ATC” displays if an ATC probe is connected. Otherwise “MAN”
displays.
7. LOBAT: Low battery indicator.
8. pH / mV: Unit and mode indicators.
FIGURE 3 FRONT VIEW

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MODES OF THE METER (See Notes 2 and 3)
1. pH-AUTOLOCK mode:
The meter will display pH and temperature
with both pH and AUTOLOCK on.
WAIT flashes until the unit detects a stable
reading.
2. mV-AUTOLOCK mode:
The meter will display mV and temperature
with both mV and AUTOLOCK on.
WAIT flashes until the unit detects a stable
reading .
3.pH mode:
The meter will display pH and temperature
with pH on but AUTOLOCK off.
4.mV mode:
The meter will display mV and temperature
with mV on but AUTOLOCK off.
5.RECALL mode:
User can recall data saved in memory.
“℃”annunciator will flash.
←Site number
6.ERASE mode:
User can erase ALL data saved in memory.

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OPERATIONAL PROCEDURES
Before operation, you should turn on the unit.
BUFFER TABLE SELECTION
This unit has two buffer sets: 4.01,7.00, 10.01pH and 4.00,6.86, 9.18pH. To change
the buffer set, turn off the unit, then press and hold the STAND key while turning on
the unit again. The user can select 1-point, 2-point or 3-point pH calibration. The first
point must be 7.00/6.86 buffer. The second and the third will be either 4.01 or 10.01
when the first point is 7.00. If the first is 6.86 then the second and the third will be
either 4.00 or 9.18.
pH CALIBRATION
1. Calibration in the pH-AUTOLOCK mode.
1.1 Connect the pH electrode to the BNC connector and ATC/Temp probe to the
ATC/Temp connector of the unit. The ATC will be on. Press the MODE
key repeatedly until the unit displays pH-AUTOLOCK mode.
1.2 Rinse the pH electrode and ATC/Temp probe in distilled water and immerse
in the first buffer solution. The unit will display the buffer temperature.
NOTE: If no ATC/Temp probe is connected, the MAN will be on, adjust the
temperature reading (0.0 to 60.0 ℃) to that of the first buffer using the △
and ▽keys.
1.3 Press the STAND key to calibrate. The pH annunciator flashes until the unit
exit pH calibration. The STAND annunciator will be on, and the WAIT
annunciator flashes until the unit detects a stable reading. When a stable
reading is reached, the WAIT annunciator will stop flashing and stay off.
The SLOPE annunciator will start to flash. This means that the first point
has been calibrated.
You can press the MODE key to exit for one point pH calibration. The pH
annunciator will stop flashing and be on, and the meter is ready for
measurements with STAND on but SLOPE off. If dual or three points
calibration is needed, go to 1.4.
1.4 Remove the pH electrode and ATC/Temp probe from the buffer and rinse
them in distilled water. After rinsing, immerse them in the second buffer
solution.
NOTE: If no ATC/Temp probe is connected, the MAN will be on, adjust the
temperature reading (0.0 to 60.0 ℃) to that of the second buffer using the
△and ▽keys.

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1.5 Press the SLOPE key to calibrate. The SLOPE annunciator will stop
flashing and stay on. And the WAIT annunciator flashes until the unit
detects a stable reading. When a stable reading is reached, the WAIT
annunciator will stop flashing and stay off. This means that the second point
has been calibrated.
You can press the MODE key to exit for dual points pH calibration. The pH
annunciator will stop flashing and be on, and the meter is ready for
measurements with both STAND and SLOPE on . If three points calibration
is needed, go to 1.6.
1.6 Remove the pH electrode and ATC/Temp probe from the buffer and rinse
them in distilled water. After rinsing, immerse them in the third buffer
solution.
NOTE: If no ATC/Temp probe is connected, the MAN will be on, adjust the
temperature reading (0.0 to 60.0 ℃) to that of the third buffer using the △
and ▽keys.
1.7 Press the SLOPE key to calibrate. The WAIT annunciator flashes until the
unit detects a stable reading. When a stable reading is reached, the WAIT
annunciator will stop flashing and stay off. This means that the third point
has been calibrated.
You can press the MODE key to exit for three points pH calibration. The
pH annunciator will stop flashing and be on, and the meter is ready for
measurements with both STAND and SLOPE on.
2. Calibration in the pH mode.
2.1 Connect the pH electrode and ATC/Temp probe to the top of the instrument.
The ATC annunciator will be on. Press the MODE key repeatedly until the
unit displays pH mode.
2.2 Rinse the pH electrode and ATC/Temp probe in distilled water and immerse
them in the first buffer solution. The instrument will display the buffer
temperature.
NOTE: If no ATC/Temp probe is connected, the MAN will be on, adjust the
temperature reading (0.0 to 60.0 ℃) to that of the first buffer using the △
and ▽keys.
2.3 Allow sufficient time for the electrode and ATC/Temp probe to stabilize.
Press the STAND key to calibrate. The pH annunciator flashes until the unit
exit pH calibration. The STAND annunciator will be on and the SLOPE
annunciator will flash, indicating that the first point has been calibrated.

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You can press the MODE key to exit for one point pH calibration. The pH
annunciator will stop flashing and be on, and the meter is ready for
measurements with STAND on but SLOPE off. If dual or three points
calibration is needed, go to 2.4.
2.4 Remove the pH electrode and ATC/Temp probe from the buffer and rinse
them in distilled water. After rinsing, immerse them in the second buffer
solution.
NOTE: If no ATC/Temp probe is connected, the MAN will be on, adjust the
temperature reading (0.0 to 60.0 ℃) to that of the second buffer using the
△and ▽keys.
2.5 Allow sufficient time for the pH electrode and ATC/Temp probe to stabilize.
Press the SLOPE key to calibrate. The SLOPE annunciator will stop
flashing and stay on. This means that the second point has been calibrated..
You can press the MODE key to exit for dual points pH calibration. The pH
annunciator will stop flashing and be on, and the meter is ready for
measurements with both STAND and SLOPE on. If three points calibration
is needed, go to 2.6.
2.6 Remove the pH electrode and ATC/Temp probe from the buffer and rinse
them in distilled water. After rinsing, immerse them in the third buffer
solution.
NOTE: If no ATC/Temp probe is connected, the MAN will be on, adjust the
temperature reading (0.0 to 60.0 ℃) to that of the third buffer using the △
and ▽keys.
2.7 Allow sufficient time for the pH electrode and ATC/Temp probe to stabilize.
Press the SLOPE key to calibrate. The third point has been calibrated.
You can press the MODE key to exit for three points pH calibration. The pH
annunciator will stop flashing and be on, and the meter is ready for
measurements with both STAND and SLOPE on.
pH MEASUREMENTS
1. Measurement in the pH-AUTOLOCK mode.
1.1 Connect the pH electrode and ATC/Temp probe to the unit. The ATC
annunciator will be on.
1.2 Press the MODE key repeatedly until the unit displays pH-AUTOLOCK
mode.
1.3 Rinse the pH electrode and ATC/Temp probe with distilled water and

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immerse them in the sample to be measured.
1.4 Press the MEASURE key. The WAIT annunciator will flash until the unit
determines a stable pH reading. When WAIT stops flashing and stays off,
the reading is locked.
NOTE: If no ATC/Temp probe is connected, the MAN will be on, adjust the
temperature reading (-10.0 to 120.0 ℃) to that of the sample using the △
and ▽keys.
1.5 For inherently unstable samples, the unit will not AUTOLOCK. Use the pH
mode with AUTOLOCK off in this case.
2. Measurement in the pH mode.
2.1 Connect the pH electrode and the ATC/Temp probe to the unit. The ATC
annunciator will be on.
2.2 Press the MODE key repeatedly until the unit displays pH mode.
2.3 Rinse the pH electrode and ATC/Temp probe with distilled water and
immerse them in the sample to be measured.
2.4 Allow sufficient time for the display to stabilize. The unit will display the
pH value of the sample at the displayed sample temperature.
NOTE: If no ATC/Temp probe is connected, the MAN will be on, adjust the
temperature reading (-10.0 to 120.0 ℃) to that of the sample using the △
and ▽keys.
TEMPERATURE MEASUREMENTS
The meter can measure temperature independently with the ATC/Temp probe without
using the pH electrode.
1. Place the ATC/Temp probe in the media to be measured. The measured
temperature is displayed.
2. OuE or Und will be displayed if the temperature is out of the temperature
measurement range of –10.0 to 120.0℃. Once the temperature is brought within
range, OuE or Und will disappear and the correct temperature reading will be
displayed.
mV MEASUREMENTS
1. Measurement in the mV -AUTOLOCK mode.
1.1 Connect the optional combination ORP electrode to the unit.
1.2 Press the MODE key repeatedly until the unit display mV-AUTOLOCK
mode.
1.3 Rinse the electrode with distilled water and immerse it in the sample to be

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measured.
1.4 Press the MEASURE key. The WAIT annunciator will flash until the unit
determines a stable mV reading. When WAIT stops flashing and stays off,
the reading is locked.
1.5 The ATC/Temp probe can be used to measure the sample temperature as
required.
1.6 For inherently unstable samples, the unit will not AUTOLOCK. Use the
mV mode with AUTOLOCK off in the case.
2. Measurement in the mV mode.
2.1 Connect the optional combination ORP electrode to the unit.
2.2 Press the MODE key repeatedly until the unit display mV mode.
2.3 Rinse the electrode with distilled water and immerse it in the sample to be
measured.
2.4 Allow sufficient time for the display to stabilize. The unit will display the
mV value of the sample.
2.5 The ATC/Temp probe can be used to measure the sample temperature as
required.
SAVING, RECALLING AND ERASING DATA (See Notes 2 and 3)
1. Saving readings to memory.
1.1 While in pH-AUTOLOCK, mV-AUTOLOCK, pH and mV modes, press
and hold the MEASURE key for about 2 seconds. The unit will display
“SAV” and the site number for a brief moment to indicate a successful
saving.
1.2 If it displays “FUL”, this means that all 40 sites are used up. You should
export data from the unit as soon as possible. Any subsequent saving of
data will overwrite the existing data.
2. Recalling readings from memory.
2.1 To recall the data, press the MODE key repeatedly until the unit displays
RECALL mode. The “℃” annunciator flashes until the unit exit the
RECALL mode.
2.2 Press ∆or ∇keys to adjust / select the site number.
2.3 Press the MEASURE key to display the data that has been saved on the
selected site number. The unit will display pH and temperature, and press the
MEASURE key again to display mV and temperature. By pressing the
MEASURE key, the meter will display these two sets of stored values
alternately.
3. Erasing data.

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3.1 To erase ALL the data stored in memory, press the MODE key repeatedly
until the unit displays ERASE mode.
3.2 Press ▽and MEASURE keys simultaneously and wait for the secondary
display to count down to zero. The meter will then display “dOn” to indicate
successful erasure and will return to pH-AUTOLOCK mode automatically.
RS-232C INTERFACE OPERATION (See Note 1)
INTRODUCTION
The RS-232C interface feature can track all displayed values and interface your Jenco
meter with recorders, printers, computers, etc. For example, the user can log all data
simultaneously to an interfaced IBM PC/AT compatible computer.
This section assumes you are familiar with the basics of data communication, the
RS-232C interface, programming with computer languages, like Delphi, VB, VC, etc.
A simple program must be written in order to send command and receive data from
the unit.
If you do not have that knowledge, you must have a rudimentary knowledge and a
copy of the more popular Windows® 98 operating system or a later version of
Microsoft’s Windows®operating system capable of using COM port. In addition you
must also have an interface cable of the DB-9 type (sometimes also called a Serial
port connector) and that the wiring of that connector is wired to be compatible to the
RS-232C standard for RxD, Receive Data and TxD, Transmit Data and Circuit
Common.
To use the RS-232C interface, you must choose either to download on line from the
Jenco website at http://www.jencoi.com/ a general Windows® compatible program
that allows you to receive data from the Jenco meter as pre-programmed by that
Windows® compatible program or you must custom write your own simple program
to send the commands you want to the Jenco meter and to receive back the specific
data sampled at the time intervals you specify in your custom written program.
PREPARATION
The Jenco unit communicates with a PC computer (IBM PC/AT compatibles) through
a DB-9 interface connector. The DB-9 must be configured to be compatible with the
RS-232C standard for TxD, RxD and Circuit Common. (Please see accompanying
diagram.) After you have connected the cable, turn on both the Jenco unit and the
computer, you are now ready for the software part of the operation.
DB-9 CONNECTOR CABLE
Below is the wiring diagram showing the DB-9 connector wired to be compatible to

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the RS-232C standard for TxD, RxD and Circuit Common.
Note: The “Standard RS-232C” cable is a 25-Pin connector. The essential Circuit
Common and TxD and RxD are shown here adapted to the DB-9 connector.
DTE DCE
Data Terminal Equipment Data Communications Equipment
( Your computer or recorder, etc.) ( Your Jenco Meter.)
SOFTWARE
A demo program and the protocol are included in the accompanying CD. Using the
demo, you can easily track or recall data from the Jenco meter. Please read the
protocol to understand more about the procedure in detail. You may also choose to
download from our website a pre-programmed Windows® compatible program but
you will be limited to tracking and recalling data as preset in those programs.
ERROR INDICATIONS
Main
Display
Second Display Mode/ State Reasons
OuE
OuE
Out of 0～60℃
0～60℃
STAND
calibration
Buffer temperature is out of the 0 to 60℃range.
pH electrode offset is greater/less than ±1.5pH.
Buffer is not correct.
OuE
OuE
Out of 0～60℃
0～60℃
SLOPE
calibration
Buffer temperature is out of the 0 to 60℃range.
pH electrode slope is off by more than 30% of ideal
slope.
Buffer is not correct.
OuE/Und
OuE
-10.0～120℃
OuE/Und
pH
measurement
pH value is out of the –2.00 to 16.00 pH range.
Temperature is out of the –10.0 to 120℃range.
OuE/Und mV
measurement
mV value is out of the –1999 to 1999 mV range.
Transmit Data! Pin 2
Receive Data? Pin 3
Circuit Common Pin 7
Pin 2 Receive Data?
Pin 3 Transmit Data !
Pin 7 Circuit Common

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OuE/Und Temperature
measurement
Temperature is out of the –10.0 to 120℃range.
bAd EEP Failed to check or write EEPROM.
pH BUFFERS
The temperature characteristics of pH calibration buffers 4.00, 4.01, 6.86, 7.00, 9.18
and 10.01 are stored inside the instrument. The buffers used to calibrate the
instrument must exhibit the same temperature characteristics as the stored values.
TEMPERATURE COEFFICIENT OF THE pH BUFFERS
°C 4.00 6.86 9.18 4.01 7.00 10.01
0 4.01 6.98 9.46 4.01 7.11 10.32
5 4.00 6.95 9.39 4.01 7.08 10.25
10 4.00 6.92 9.33 4.00 7.06 10.18
15 4.00 6.90 9.28 4.00 7.03 10.12
20 4.00 6.88 9.23 4.00 7.01 10.06
25 4.00 6.86 9.18 4.01 7.00 10.01
30 4.01 6.85 9.14 4.01 6.98 9.97
35 4.02 6.84 9.10 4.02 6.98 9.93
40 4.03 6.84 9.07 4.03 6.97 9.89
45 4.04 6.83 9.04 4.04 6.97 9.86
50 4.06 6.83 9.02 4.06 6.97 9.83
55 4.07 6.83 8.99 4.08 6.97 9.80
60 4.09 6.84 8.97 4.10 6.98 9.78
Table 1
The actual reading of the instrument can differ from the values shown by ±0.01 pH.

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SPECIFICATIONS
Display RANGE ACCURACY RESOLUTION
pH -2.00 to 16.00 pH ±0.01 pH 0.01 pH
mV -1999 to +1999 mV ±0.05% F.S. 1 mV
Temperature -10.0 to 120.0 ℃±0.3 ℃0.1 ℃
pH BUFFER RECOGNITION (4.01,7.00,&10.01) or (4.01, 6.86, &9.18)
pH BUFFER TEMP. RANGE 0 to 60 ℃
pH ELECTRODE OFFSET
RECOGNITION ±90 mV at pH 7.00 or 6.86
pH ELECTRODE SLOPE RECOGNITION ±30% at pH 4.00,4.01, 9.18, or 10.01
pH CALIBRATION 1 point / 2 points / 3 points
CALIBRATION VALUE BACK-UP Yes
pH TEMP. COMPENSATION AUTO / MANual, -10.0 to 120.0 ℃
AUTOLOCK Yes
ATC PROBE Thermistor (10kΩat 25℃)
INPUT IMPEDANCE >1012Ω
POWER SUPPLY: Batteries / Adaptor 6 AAA batteries/AC adaptor (Output: DC 9V)
AUDIO FEEDBACK All Touch Keys
LCD SIZE: pH/mV: Temp. 12.5 mm: 7.5 mm High
STORAGE CAPABILITY 40 sets of readings (For 6230M / 6231M only)
COMMUNICATION RS-232C Output (For 6230M / 6230N only)
AMBIENT TEMP. RANGE 0 to 50 ℃
RELATIVE HUMIDITY Up to 95%
DIMENSIONS 86mm×241mm×72mm
WEIGHT (Batteries not included) 350gm
WARRANTY
Jenco Instruments, Ltd. Warrants this product to be free from significant deviations in
material and workmanship for a period of 1 year from date of purchase. If repair or
adjustment is necessary and has not been the result of abuse or misuse, within the
year period, please return-freight-prepaid and the correction of the defect will be
made without charge. If you purchased the item from our Jenco distributors and it is
under warranty, please contact them to notify us of the situation. Jenco Service
Department alone will determine if the product problem is due to deviations or
customer misuse.
Out-of –warranty products will be repaired on a charge basis.

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RETURN OF ITEMS
Authorization must be obtained from one of our representatives before returning
items for any reason. When applying for authorization, please have the model and
serial number handy, including data regarding the reason for return. For your
protection, items must be carefully packed to prevent damage in shipment and insured
against possible damage or loss. Jenco will not be responsible for damage resulting
from careless or insufficient packing. A fee will be charged on all unauthorized
returns.
NOTE: Jenco Instruments, Inc reserves the right to make improvements in design,
construction, and appearance of our products without notice.
JENCO INSTRUMENTS, INC.
7968 Arjons Drive, Suite C,
San Diego, CA 92126 USA
TEL: [phone] FAX: [phone]
E-MAIL: [e-mail] ; [email protected]
Homepage: http://www.jencoi.com/
JENCO ELECTRONICS, LTD.
PO. BOX LINKOU 117
TAIPEI, TAIWAN
TEL: [phone] FAX: [phone]
E-MAIL: [email protected].net
Homepage: http://www.jenco.com.cn/big5/
SHANGHAI JENCO ELECTRONICS, LTD.
18 Wang Dong Zhong Road
Sijing Town,Songjiang
SHANGHAI,CHINA
TEL: [phone] FAX: [phone]
E-MAIL: [email protected]
Homepage:http://www.jenco.com.cn/

2010-2-25（V02）：修改美国和中国的 EMAIL 地址。
英文使用说明书 Manual in English
机型 6230M/6230N/6231M/6231N 编制人 豆林奇 编制日期 2003/12/11
文件编号 K6230M/6230N/6231M/6231N-01 修改人 杨启娜 修改日期 2010-2-25
版本号 02 核准人 杨健寿 核准日期 2010-2-25