TPI 390a User Manual

390a

Digital Salt / TDS Meter

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Contents

Before Use........................................................ 1

Description....................................................... 1

Applications...................................................... 1

Precautions...................................................... 2

Overview......................................................... 3

Functions........................................................ 4

LCD Symbols...................................................... 5

Specifications.................................................... 5

Measuring Salt, TDS, and Temperature................. 6

Battery Replacement and Troubleshooting................... 7

Definition of Total Dissolved Solids (TDS)................... 8

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Before Use

Please carefully read the Operators Manual before using this meter.
Clean the sensor area with a neutral detergent using a soft cloth or
sponge before and after use.

Description

The 390a measures the concentration of dissolved salt in percent and
Total Dissolved Solids (TDS) in ppm. Temperature in Celsius or
Fahrenheit is also measured.
Simply immerse the tip into liquids to determine salt content, TDS
level, and temperature.

Applications

Water - Test TDS levels to determine purity.

Food - Test the amount of salt in food, seafood, or processed foods.

Health - Monitor the amount of salt intake.

Water Filtration - Test for TDS to determine performance level of filtra­tion systems.

HVAC -

- Test condensate water in cooling tower and humidifier reservoirs to
prevent bacterial growth and drain line corrosion.

- Reduce water and chemical consumption in boilers and cooling tow­ers.

- Test TDS levels in make-up water to prevent scale formation, corro­sion, and embrittlement.

- Determine when to perform blowdown and add make-up water.

- Prevent contamination and corrosion of control valves, heat exchang­ers, and steam traps.

- Verify automated TDS controllers are functioning properly.

- Prevent low quality wet steam generation in boilers due to foaming
caused by high TDS levels.

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1. Precautions

Before use please read this operation manual and observe the procedures
and methods specified to ensure accurate, reliable measurements.

Only the sensor area is waterproof, please be careful to avoid getting water
into the body from above the probe.

Use care when cleaning the instrument by using a wet cloth or tissue. Use
of chemicals such as acetone or benzene may cause deterioration of the
housing material (ABS) or cause the device to not work properly.
Never attempt to disassemble or modify this product.

If the sensor is exposed to temperatures below 0°C (32°F) or above 100°C
(212°F) for an extended period of time damage may occur.

Please wash the sensor using a neutral detergent and soft cloth or sponge
before and after use. After rinsing fully with water, wipe the sensor softly
using dry cloth or tissue and always keep dry while not in use.

While measuring, make sure the sensor does not contact the bottom or
sides of the container or any solid material within the measured sample. If
contact is made with the container or solid material the displayed reading
might be lower than the actual value.

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2. Overview

On / Off Button

Mode Button

Hold / Cal Button

LCD Display

Sensor

Factory Probe Access
Do not open

Battery compartment.
Unscrew to change
batteries.

The 390a uses two
CR2032 batteries.

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3 Function

Sensor

Used to measure Salt concentration, TDS level, and Temperature. This
area is waterproof.

(ON/OFF) Key

Used to turn the power on and off. After use, the power turns off auto­matically within one minute.

(MODE) Key

Measurement Mode Selection:

Use the Mode button to select the measurement mode: Salt concentra­tion in percent (%), Total Dissolved Solids (TDS) in ppm or
Temperature in °C or °F. When the power is turned on, the default
mode is the Salt %.

Repeatedly press the Mode button to switch between each display.

Switching Between Celsius and Fahrenheit:

The Mode key is also used to switch between degrees C and F. When
the temperature is displayed, press and hold the Mode button until the
display changes to °C or °F depending on which is currently displayed.

Hold / CAL Key

Used to freeze the measured value during a test or perform calibration.
Please refer to section (5) and (6) for calibration instructions.

While measuring press the Hold/Cal button to freeze the display. Press
the button again to return the 390a to normal operation.

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4. LCD display Symbols

Display Description

°C / °F Indicates the temperature of the measurement sample.

% Indicates the salt concentration of the sample.

TDS Indicates the level of Total Dissolved Solids in ppm**

HOLD Indicates the hold function is activated

Indicates the batteries need replacement.

Error Indicates the measurement range has been exceeded.

5. Specifications

Salt measurement range: 0 to 5.0%
Accuracy: 0.1% to 2% = +/-0.2%

2% to 5% = +/-0.3%

Temperature measurement range: 32°F to 212°F (0°C to 100°C)
Accuracy:

TDS Range: 0ppm to 2000ppm
Accuracy: +/-20ppm

Power Supply: CR2032 battery (2 pcs)

Battery life: Approximately 6 months based on 3 uses per day

Size: 215 (L) × 26 (W) x 30 (D) mm (0.7"× 1.3"× 10.0")

Weight: 57g (2oz) (including batteries)

50°F to 86°F (10°C to 30°C) = +/-2°F (+/-1°C)

<50°F & >86°F (<10°C & >30°C) = +/-4°F (+/=2°C)

Measurement method: Electric Conductivity measurement system

** See Appendix A for an explanation of TDS.

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6. Measuring Salt, TDS, and Temperature

(1) Remove the protective cap. Turn the 390a on and the salt concentration
is displayed. Fully immerse the sensor into the liquid to be measured. If a
solid food is being measured, break it into pieces and dilute it with water.
Allow approximately 10 seconds for the reading to stabilize. After the read­ing stabilizes, push the Mode button to select the TDS level and tempera­ture measurement modes. (To switch between °C/°F units, when tempera­ture is displayed press and hold the ‘MODE’ key until the display changes.)

(2) Pushing the 'HOLD /CAL' switch will freeze the display and 'HOLD'
appears on the display. Remove the salt meter from the sample and after
confirming the measured value, press the 'HOLD/CAL' switch to deactivate
display hold.

(3) Wash the sensor with a neutral detergent using a soft cloth or sponge
each after use and rinse with water. Dry the sensor and store with the sen­sor cover installed.

Note: Use the included spoon attachment as needed to test samples.

Sample Location for Accurate Measurement

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7. Battery Replacement & Troubleshooting

Replace the battery when the battery symbol appears on the display.

(1) Unscrew the cover at the top of the main body. Pull out the used bat­teries. Observing polarity insert two new batteries (CR2032 type). The neg­ative side of the batteries face the spring.

(2) Screw the cover on and turn on power to confirm the batteries were
replaced correctly.

Problem

Cause Corrective Action

LCD display dim Exceeded service Replace batteries.
or not working. life of batteries

Unstable readings Contamination of Clean the sensor area

sensor

8. Calibration

Perform calibration if readings begin to drift.

1. Press the Power button (ON/OFF).

2. If necessary, press the Mode button to set the 390a to % Salt mode.

3. Put the sensor into 0.9% saline solution.
(Make sure the sensor does not contact bottom or sides of the calibration
sample)

4. While the sensor is in the solution, press and hold down the HOLD/CAL
button until the display blinks. Release the HOLD/CAL button and wait.

5. When the display stops blinking calibration is complete.

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Appendix A

Definition of TDS (Total Dissolved Solids)

TDS is the sum of all inorganic particulate material. Water contains a
variety of minerals and salts, such as calcium, magnesium, carbonate,
chloride and nitrate etc. TDS is the parameter used when measuring
the total sum of all these compounds in water.

TDS is an indicator used for wastewater analysis and measuring min­eral content of water.

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