JENCO EC3840 User manual

Operation Manual
Hand-held Conductivity/Salinity/TDS/
Temperature Meter
EC3840

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CONTENTS
GENERAL INTRODUCTION………………....................2
INITIAL INSPECTION……...………………....................2
WATER PROOF…….……...………………....................2
INSTALLING THE BATTERIES..…………....................3
DISPLAY & KEYS FUNCTIONS…..……………...…………4
A. Display ................................................................4
B. Keys.....................................................................5
OPERATIONAL PROCEDURES..…….........................5
A. Preparing Standard Solutions................................5
B. Calibration........................................................6
C. Conductivity Measurements....................................7
ERROR DISPLAYS AND TROUBLESHOOTING.........8
SPECIFICATIONS………………..……..........................9
WARRANTY………………………….........................10

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GENERAL INTRODUCTION
Thank you for selecting the EC3840 meter. The EC3840 is a
precision tool that measure conductivity, salinity, TDS and
temperature. A built-in microprocessor stores, calculates and
compensates for all parameters related to conductivity and
temperature determinations.
This unit has a waterproof IP67 case. The touch mode keys are
highly reliable with tactile and audio feedback. This meter uses four
“AAA” batteries. Re-calibration is not required when power is
restored.
The front of the meter has a large LCD that displays temperature
and either temperature compensated or non-temperature
compensated conductivity, salinity or TDS simultaneously along
with user prompts and mode indicators. The unit prompts the user
through calibration and measurement procedures.
The model EC3840 is available with a single four-wire conductivity
cell. Other features include automatic conductivity ranging,
automatic temperature compensation, long battery life, and 50/60
Hz AC noise rejection. This unit is universal and user-friendly, for
field, industrial and laboratory applications.
INITIAL INSPECTION
Carefully unpack the unit 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.
WATER PROOF
Though the EC3840 meter is housed in a watertight case, DO NOT
use it underwater. The watertight case prevents permanent damage
to the unit if accidentally dropped into non-corrosive solutions.
Follow these steps immediately if the unit is immersed in any
solution:
1. Rinse unit carefully with distilled water. After rinsing and drying,
inspect and clean connectors to remove all contaminants that
may affect probe connections.
2. Wait for the unit and probe to dry completely before resuming
operation.

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3. If the unit does not function correctly after steps1 and 2, call
JENCO for possible repair or replacement (see Warranty).
INSTALLING THE BATTERIES
The EC3840 meter is packaged with 4 “AAA” alkaline batteries
required for operation. To insert the batteries into the meter, follow
the procedure outlined below.
1. Use a screw driver to remove the two screws and battery cover
to expose the battery compartment. (Figure 1.)
2. Note the polarity and insert the batteries into the battery
compartment correctly.
3. Replace the battery cover and make sure to secure the two
screws for the water-tight feature.
[Note: Press the “On/Off” key to turn the unit on. If the unit is
running then you can press the “On/Off ” key to turn the unit off.
The unit will automatically turn off after 10 minutes of no key
activity.]
Figure 1: Battery compartment

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DISPLAY & KEYS FUNCTIONS
A. Display
1
2
3
4
5
6
7
8
9
10
11
12
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Figure 2: Active LCD screen
1. CONDUCTIVITY-
Displays when measuring
conductivity.
8. CELL-
Indicates conductivity cell
constant value.
2. BAT-
Low battery indicator.
9. ℃/%-
Displays during calibration:
℃:Indicates temperature
reference unit.
%: Indicates temperature
coefficient unit.
3. UNCOMPENSATED-
Distinguish between
temperature compensated and
non-temperature compensated
reading.
10. ppt-
Parts per thousand; indicates
salinity measurement.
4. MAIN DISPLAY-
For compensated and
uncompensated conductivity,
salinity and TDS values.
11. uS/mS-
microsiemens or millisiemens,
indicates conductivity
measurement.
5. CAL-
Calibration mode indicator 12. g/L-
Grams/Liter; indicates TDS
measurement.
6. TDS-
Displays when measuring total
dissolved solids.
13.Temperature and unit
display
7. SALINITY-
Displays when measuring
salinity.

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B. Keys
On/Off-
Powers on and shuts off the meter.
Mode
Mode-
Selects display mode. In normal operation, press
Mode to sequentially display compensated
conductivity, salinity, total dissolved solids (TDS) and
uncompensated conductivity. In calibration mode,
this key exits the current calibration and displays the
next calibration parameter.
Up/Down-
Increases or decreases the display value as desired.
Cal
Cal-
In normal operation, changes the mode from Normal
to Calibration.
Enter
Enter-
In Calibration Set-up, press this key to save the
current parameter to memory.
OPERATIONALPROCEDURES
A. Preparing Standard Solutions
Suitable conductivity standards are available commercially or the
user can prepare them using research grade reagents.
Here are some standard solutions the user can prepare to calibrate
the probe of the model EC3840.
1. Standard solution of 1413uS at 25℃: Accurately weight out
0.746 grams of research grade dried Potassium Chloride
(KCL). Dissolve in 1000ml of distilled water.
2. Standard solution of 12.90mS at 25℃: Accurately weight out
7.4365 grams of research grade dried Potassium Chloride
(KCL). Dissolve in 1000ml of distilled water.

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3. Standard solution of 111.9mS at 25℃: Accurately weight out
74.264 grams of research grade dried Potassium Chloride
(KCL). Dissolve in 1000ml of distilled water.
[Note: You can store the remaining solution in a plastic
container for one week but the air space between the cap and
the solution must be kept to an absolute minimum. Storing the
excess solution below 4℃can increase the storage life. If you
have any doubt of the accuracy of the stored solution, a fresh
batch should be prepared.]
B. Calibration
Calibration setup contains five sections: TDS, Cell, Temperature
Coefficient, Temperature reference and Conductivity Calibration. To
access these sections:
1. Connect the conductivity probe 3840P to the unit and turn the
unit on. The screen will display CELL and the cell constant of
the conductivity probe.
2. Allow temperature reading to stabilize, press “Cal” key to
enter the calibration mode. CAL appears on the LCD. Press
“Mode” key to sequentially display the following sections:
[Note: Press “Enter”key to accept any values changes in
each section and automatically advance to the next section. If
there are no changes, the unit accepts the current value and
proceeds to the next section.]
TDS
TDS is determined by multiplying conductivity (mS) by a TDS
factor. The default factor value is 0.65. To change the TDS
factor, use the up and down keys to adjust the value between
0.30 and 1.00. Press “Enter” key to save the new value, or
press “Mode” key to cancel the change and display the CELL
screen.
CELL
The second screen will display CELL and the current cell
value. The default cell value is 0.50 and is displayed in the
lower right of the screen. The unit allows a variance of +/-0.15
before displaying an error message. The cell value can’t be
adjusted at this screen; calibrating conductivity is the only
way to adjust the cell constant. Press “Enter” key to reset the
cell constant to 0.50 and display the Temperature
Coefficient screen.

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[Note: Be certain to press “Enter” key to reset the cell
constant to 0.50. If “Mode” key is pressed, the unit retains the
previous cell constant and calibrates from a value that is
already offset.]
Temperature Coefficient
The unit uses the temperature coefficient to calculate
temperature compensated conductivity. The default value is
1.91%. To change the temperature coefficient, use the up and
down keys to adjust the value between 0 and 4.00%. Press
“Enter” key to save the new value, or press “Mode” key to
cancel the change and display the Temperature Reference
screen.
Temperature Reference
The unit uses the temperature reference value to calculate
temperature compensated conductivity. The default value is
25℃. To change the temperature coefficient , use the up and
down keys to adjust the value between 15 and 25℃. Press
“Enter” key to save the new value, or press “Mode” key to
cancel the change and display the Conductivity Calibration
screen.
Conductivity Calibration
(a) Immerse the probe in a standard of known conductivity,
preferably a standard in the middle range of the solutions
to be measured. Immerse the probe (at least 2” to 3” or
5~7cm from the tip) without touching the sides of the
calibration container. Shake the probe lightly to remove
any air bubbles trapped in the conductivity cell.
(b) Allow temperature to stabilize. The message “rAGE”
(range) may display briefly to indicate unit auto-ranging;
this is normal. After temperature stabilization, use the up
and down keys to adjust the conductivity value to that of
the conductivity standard at 25℃. Press “Enter” key to
calibrate. The unit beeps twice to indicate a successful
calibration, Then automatically switches to normal
operation mode.
B. Conductivity Measurements
1. Turn the unit on. Place the probe in the solution to be
measured. Immerse the probe (at least 2” to 3” or 5~7cm
from the tip). Shake the probe lightly to remove any
trapped air bubbles in the conductivity cell.

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2. Press “Mode” key to enter the desired measurement
mode. The message “rAGE” (range) may appear briefly
on the display indicate auto-ranging; this is normal. Allow
temperature to stabilize before taking measurements.
ERROR DISPLAYS AND TROUBLESHOOTING
[
Note: If the unit still does not perform normally after the above
measures are taken, call Jenco Service Department.]
Main
Display Secondary
Display Possible cause(s) Corrective
Action(s)
"over" during
measurements /
●Conductivity is
> 200.0mS.
●Salinity is
> 70.0ppt.
"over " during
calibration /
Cell Constant
Calibration is out
of range.
●Ensure the probe is
immersed at least
2”~3” or 5~7cm from
the tip, below the
surface of the
sample/standard
solution.
●Allow sufficient time
for the electrode and
Temp probe to
stabilize.
●Recalibrate with
correct value for the
conductivity
standard.
●Replace
conductivity
standard.
●Clean cell.
over Temperature >
90.0℃
"over " during
measurements undr Temperature <
-10.0℃
Decrease/Increase
the sample
temperature.

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SPECIFICATIONS
Display Range Resolution Accuracy
Conductivity
0.0 to 499.9uS/cm
500 to 4999uS/cm
5.00 to 49.99mS/cm
50.0 to 200.0mS/cm
0.01uS/cm
1uS/cm
0.01mS/cm
0.1mS/cm
±1% of reading + 2uS/cm
±1% of reading + 5uS/cm
±1% of reading +0.05mS/cm
±2.5% of reading + 0.5mS/cm
Salinity 0.0 to 70.0ppt 0.1ppt ±0.2% Full Scale
Temperature -10.0 to 90.0 °C 0.1 °C ±0.2°C or ±0.4% Full Scale,
whichever is greater.
Reference Temperature 15.0 to 25.0 °C
Temperature Coefficient 0.0% to 4.0%
Cell Constant 0.5 ± 0.15
TDS Constant Range 0.30 to 1.00
Power Four “AAA” Batteries
Calibration Back-up EEPROM
Audio Feedback All Touch Keys
Display (pH /mV : Temp) 11mm : 7mm high LCD
Ambient Temperature Range 0 to 50 °C
Relative Humidity up to 90%
Case IP67 water-tight case
Dimensions (W x D x H) 75mm x 157mm x 35mm
Weight 230 grams
(Batteries included)

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WARRANTY
Jenco 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
free of 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.
RETURN OF ITEMS
Authorization must be obtained from one of our representatives
before returning items for any reason. When applying for
authorization, 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 authorized returns.
NOTE: Jenco reserves the right to make improvements in design,
construction and appearance of our products without notice.

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Jenco Instruments, Inc.
7968 Arjons Drive, Suite C
San Diego, CA 92126 USA
TEL: [phone]
FAX: [phone]
E-Mail: [email protected]; [e-mail]
Website: www.jencoi.com
Jenco Electronics Inc.
P.O. Box Linkou 117
Taipei, Taiwan
TEL: [phone]
FAX: [phone]
Shanghai Jenco Instruments, Ltd.
18 Wang Dong Zhong Road
Sijing Town, Songjiang
Shanghai, China
TEL: [phone]
FAX: [phone]
E-Mail: [email protected]
Website: www.jenco.com.cn

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