Extech ExStik II EC400
User Manual
Conductivity / TDS / Salinity / Temperature Meter
Introduction
Congratulations on your purchase of the EC400 Conductivity / Total Dissolved Solids (TDS) / Salinity / Temperature meter. The EC400 uses dynamic cell-constant technology, allowing one electrode to do the job of many. Careful use and maintenance will provide years of reliable service.
Powering the Meter
The EC400 uses four (4) CR2032 lithium-ion batteries (included). If the batteries are weak, the BAT ? indicator appears. Press the ON/OFF key to switch ON/OFF the EC400. The auto power off feature switches OFF the EC400 after 10 minutes of inactivity.
Getting Started
- Remove the cap from the bottom of the meter to expose the conductivity electrode.
- Before the first use, or after storage, rinse the electrode in deionized water and dry.
- For best results, calibrate conductivity with a standard in the expected range of the sample. For maximum accuracy calibrate from a low conductivity standard to a high conductivity standard.
- Store the electrode dry.
Meter Description
Front Panel
A handheld digital meter with a cylindrical body, tapering towards the bottom. It has a cap at the bottom for the electrode. The top has a cap. The main body features an LCD screen, several buttons (MODE/HOLD, CAL/RECALL, ON/OFF), and branding. The display shows numerical readings and indicators.
- 1. Battery compartment: Located under the top cap.
- 2. LCD: The main digital display screen.
- 3. MODE/HOLD button: Used to change measurement mode, access Data Hold, and store readings.
- 4. CAL/RECALL button: Used to initiate calibration, change temperature units, and recall stored readings.
- 5. ON/OFF button: Powers the meter on and off.
- 6. Electrode Collar: Secures the electrode to the meter body.
- 7. Electrode: The sensing probe at the bottom of the meter.
Display
A detailed view of the LCD screen, showing various indicators and readings:
- 1. Bar graph display: A graphical representation of the measurement range.
- 2. Measurement units: Displays the current unit of measurement (e.g., µS, mS, ppm, mg/L, S).
- 3. Main display: Shows the primary numerical reading (e.g., 8.8.8.8).
- 4. Indicators: Shows range calibration status (L, M, H) and low battery warning (BAT ?).
- 5. Temperature display: Shows the measured temperature in °C or °F.
- 6. Reading Hold Indicator: Displays 'HOLD' ⏸️ when a reading is frozen.
Operation
Sample Preparation
For Conductivity, TDS or Salinity, place the test sample in a sample cup with sufficient depth to cover the electrode (1 inch minimum). Stir the solution to remove air bubbles.
Measurements
- Press the ON button. The icons 8888 and SELF CAL ⚙️ will appear during power-up diagnostics.
- Long press the MODE/HOLD button to scroll to the desired measurement mode.
- Place the electrode in the sample.
- Slowly stir the solution with the electrode to remove air bubbles.
- The meter will select the proper range and display the reading.
Note: Always rinse the electrode in de-ionized water between measurements to avoid cross-contamination of the sample. Double rinsing is recommended when high accuracy is required.
Example Readings:
- Conductivity: 100.9 µS with 25.0°C
- TDS (ppm): 790 ppm with 25.0°C
- TDS (mg/L): 790 mg/L with 25.0°C
- Salinity: 790 S (ppt) with 25.0°C
Changing Measurement Function
The meter can be set to measure Conductivity, TDS, or Salinity. To change the mode:
- Long press the MODE/HOLD button for 2 seconds to begin scrolling through the units: µS (Conductivity), ppm (TDS), mg/l (TDS), ppm S (Salinity).
- When the desired units are displayed, release the MODE/HOLD button.
Note: The HOLD function cannot be engaged when changing the measurement function. If HOLD ⏸️ is displayed, short press the HOLD button to switch it OFF.
Changing Temperature Units
To change the displayed temperature units (°C, °F):
- With the meter OFF, long press the CAL/RECALL button.
- With the CAL/RECALL button pressed, short press the ON/OFF button. When SELF CAL ⚙️ appears in the display, release the CAL/RECALL button. The meter will switch ON with the newly selected units.
TDS Compensation Ratio
The TDS value is determined by multiplying a conductivity reading by a known ratio factor. The meter allows for selecting a conversion ratio in the range of 0.4 to 1.0. The ratio varies with the application but is typically set between 0.5 and 0.7.
Note: The stored ratio will briefly appear in the lower temperature display when the meter is first turned on, or when changing measurement function to TDS.
Note: In the Salinity mode, the ratio is 0.4 to 0.6 automatic.
To change the ratio, while in the TDS measurement mode (ppm or mg/l):
- Press and release the CAL/RECALL button twice in succession. The stored ratio will appear in the display.
- Press the MODE/HOLD button to increase the ratio value in steps of 0.1.
- When the desired ratio is displayed, short press the CAL/RECALL button to store the value and return to the normal mode.
- If no buttons are pressed in 5 seconds, the meter returns to measure mode.
A diagram shows a dial with a needle pointing to '0.7' and the text 'tdS' below it, indicating the TDS ratio setting.
Data Hold Mode
Press the MODE/HOLD button to freeze a reading on the display. The HOLD ⏸️ indicator will appear. This also stores the reading. Press the MODE/HOLD button again to return to normal operation.
A diagram shows the main display with a reading (e.g., 1563 µS) and the HOLD ⏸️ indicator illuminated. The lower display shows the storage location number (e.g., '4').
Low Battery Indication
When the batteries become weak, the BAT ? icon will appear. Refer to the Maintenance section for battery replacement information.
Auto Power OFF (APO)
APO switches OFF the meter after 10 minutes of inactivity.
APO Disable
- Switch ON the meter.
- Short press CAL/RECALL.
- Immediately long press the MODE/HOLD and ON/OFF buttons simultaneously for approximately 2 seconds, until oFF is briefly displayed. APO is now disabled.
- On the next power cycle, APO will be enabled again.
Storing, Recalling, Clearing Readings
Storing Readings
- Press the MODE/HOLD button to store a reading. The storage location number will be displayed on the lower display, while the main display shows the stored reading. The meter will enter the HOLD ⏸️ mode and the HOLD indicator will appear.
- Press the MODE/HOLD button again to exit the HOLD mode and return to normal operation.
- The maximum number of readings that the EC400 can store is 25. Previously stored readings (starting with number 1) are overwritten when the limit is reached.
Recalling Readings
- Press the CAL/RECALL button and then press the MODE/HOLD button. A location number (1 through 25) will briefly appear and then the value stored in that location will appear. The displayed units will flash, indicating that the storage recall mode is active.
- The last stored reading will be displayed first. Short press the MODE/HOLD button to step through the stored readings. The location number is displayed first, then the stored reading.
- To exit the storage mode, press the CAL/RECALL button; the meter will return to normal operation, after displaying End ?.
A diagram shows a sequence: a stored reading (e.g., 15 µS) transitioning to another stored reading (e.g., 1423 µS) with its associated temperature (19.5°C), indicating the recall function.
Clear Stored Memory
With the meter ON, long press the ON/OFF button for 4 seconds; clr ?️ will briefly appear when the memory has cleared.
Calibration (Conductivity)
Verify meter accuracy approximately once per month. If calibration is required, use a conductivity standard solution. The meter can be calibrated in any or all three of its ranges. ONLY standardizing solutions of 84µS/cm, 1413µS/cm, and/or 12.88mS/cm (12,880µS/cm) may be used for the automatic calibration recognition procedure. No other calibration values are permitted.
Calibration must be performed in conductivity mode. Salinity and TDS values are calculated from conductivity values, so no further calibration is required.
Note: To meet the published accuracy specifications, calibrate the meter with the conductivity standards and meter at 77°F (25°C) or as noted on the label of the standard solution.
- Fill a sample cup with the standard solution.
- Switch ON the meter and place the electrode in the solution. Tap or move the electrode in the sample to dislodge air bubbles.
- Long press the CAL/RECALL button (approximately 2 seconds) until CAL appears. The main display will start flashing.
- The meter will automatically recognize and calibrate to the solution. When the calibration is completed, the display will briefly indicate SA ✔️ and End ?, and the meter will return to the measurement mode. Note: SA ✔️ will not appear if the calibration fails.
- The L, M, or H symbol will appear for the range(s) calibrated during the current power cycle:
- L: Low range, 84µS/cm
- M: Medium range, 1413µS/cm
- H: High range, 12.88mS/cm (12,880µS/cm)
Note: Each time the calibration mode is entered, all calibration symbols on the display are cleared. However, only the calibration data for the currently calibrated range are replaced. The other two ranges retain their existing calibration data, only the symbols are removed. Calibration of all three ranges must be performed during one power-on period for all three range calibration symbols to appear.
See Reset Calibration Data to clear all calibration data from the meter.
Note: The meter allows for a 1, 2 or 3 point calibration. If calibration is done for more than one point, the lowest value standard should be done first to obtain the best accuracy.
Reset Calibration Data
Perform this procedure to clear all calibration data. Resetting the calibration data may be necessary when new calibration solutions are used or if measurement accuracy is in question.
- Switch OFF the meter.
- Long press the CAL and MODE buttons and, while holding them down, press the ON/OFF button. The display will switch ON, release all buttons.
- The display will show dFLt rSt ? (default reset) and all calibration data will be erased. If dFLt rSt does not appear, retry the procedure.
- Proceed to the calibration sections of this manual.
Operational Matrix
| Function/Action | Power Status | Mode | Button-Press Sequence |
|---|---|---|---|
| On/Off | On or Off | Any | Short press ON/OFF |
| Calibration | On | Conductivity | Long press CAL/RECALL for 2 seconds, until it enters CAL function |
| Store Reading | On | Any measure mode | Short press MODE/HOLD |
| Hold Release | On | Hold Mode | Short press MODE/HOLD |
| Enter Memory Retrieval | On | Any measure mode | Short press CAL/RECALL then short press MODE/HOLD (within 4 seconds) |
| Scroll Stored Readings | On | Memory Recall | Short press MODE/HOLD |
| Exit Memory Retrieval | On | Memory Recall | Short press CAL/RECALL |
| Clear Stored Memory | On | Any Measure Mode | Long press ON/OFF for 4 seconds, until clr ?️ is displayed. |
| Change Measurement Mode | On | Any | Long press MODE/HOLD for at least 2 seconds (the modes will scroll, until the button is released) |
| Enter Cond/TDS Ratio | On | TDS (ppm or mg/l) | Short press CAL/RECALL twice in quick succession |
| Change Cond/TDS Ratio | On | TDS ratio | Short press MODE/HOLD (to increase the ratio by 0.1) |
| Exit Cond/TDS Ratio | On | TDS ratio | Short press CAL/RECALL |
| Change Temperature Units | Off | n/a (off mode) | Long press CAL/RECALL then short press ON/OFF. Release CAL/RECALL when SELF CAL ⚙️ is lit. |
| Override Auto Power Off | On | Any measure mode | Short press CAL then simultaneously long press ON/OFF and MODE/HOLD for 2 seconds or until oFF is displayed. |
Maintenance
Battery Replacement
An illustration shows the battery compartment cap being removed, the battery carrier pulled out, and four CR2032 batteries with their positive [+] and negative [-] terminals indicated.
- Twist off the battery compartment cap.
- Holding the battery housing in place, pull out the battery carrier, using the two small tabs.
- Replace the four (4) CR2032 batteries observing correct polarity ([+] and [-]).
- Replace the battery compartment cap.
Battery Safety
- Remove and immediately recycle or dispose of used batteries according to local regulations, keeping the batteries away from children. Do NOT dispose of batteries in household trash or incinerate.
- Used batteries can cause severe injury or death.
- Call a local poison control center for treatment information.
- This unit contains four (4) CR2032, 3.0 V, lithium batteries.
- Non-rechargeable batteries are not to be recharged.
- Do not force discharge, recharge, disassemble, heat above 122°F (50°C), or incinerate. Doing so may result in injury due to venting, leakage, or explosion resulting in chemical burns.
- Ensure that the batteries are installed correctly according to correct polarity ([+] and [-]).
- Do not mix old and new batteries, different brands or types of batteries, such as Alkaline, carbon-zinc, or rechargeable batteries.
- Always completely secure the battery compartment. If the battery compartment does not close securely, stop using the product, remove the batteries, keeping the batteries away from children.
Electrode Replacement
A simplified illustration shows the electrode connector being plugged into the meter socket, with a note about the keyed connector for proper alignment.
- To remove an electrode, unscrew and completely remove the electrode collar (turn the collar counterclockwise to remove).
- Gently rock the electrode from side to side, pulling it downwards, until it disconnects from the meter.
- To attach an electrode, carefully plug the electrode into the meter socket (note that the electrode connector is keyed, ensuring proper connection).
- Tighten the electrode collar firmly enough to make a good seal (a rubber gasket seals the electrode with the meter).
Cleaning and Storage Recommendations
- When cleaning the probe, take care not to scratch or damage the platinized electrode surfaces.
- Do not touch the inner surfaces of the conductivity electrodes. Touching the surface of the platinized electrodes may damage and reduce the life of the probe.
- Store the electrode dry, in the storage cap.
| Contaminant | Cleaning Solution | Instructions |
|---|---|---|
| Water soluble substances | Deionized water | Soak or scrub gently with a soft brush. Rinse thoroughly with DI water, and dry. |
| Grease & Oil | Warm water and household detergent | Soak or scrub with a soft brush, maximum of 10 minutes. Rinse thoroughly with DI water, and dry. |
| Heavy grease & Oil | Alcohol | Maximum 5-minute soak, scrub with a soft brush. Rinse thoroughly with DI water, and dry. |
| Lime and hydroxide coatings | 10% acetic acid | Soak until coating dissolved, maximum of 5 minutes. Rinse thoroughly with DI water, and dry. |
Troubleshooting
| Problem | Possible Cause | Action |
|---|---|---|
| Reading is frozen | Unit is in HOLD mode ⏸️ | Press HOLD ⏸️ to exit mode |
| BAT message ? | Batteries are low | Replace batteries |
| Unit will not calibrate in conductivity mode | Contaminated conductivity standard | Use fresh standard |
| Unit will not calibrate in conductivity mode | Dirty probe | Clean conductivity probe (See cleaning instructions) |
| Unit will not calibrate in conductivity mode | Damaged conductivity probe | Replace electrode |
| Unit will not calibrate in conductivity mode | Trapped air bubbles | Tap or stir to release air bubbles |
| Unit will not switch ON | Batteries are low | Replace batteries |
| Unit will not switch ON | Batteries installed with incorrect polarity | Replace batteries, observing correct polarity |
| Unit will not respond to button presses | Internal fault | Remove batteries, press ON/OFF button for 10 seconds, replace batteries |
Specifications
| Display | 2000 count LCD with bar graph |
| Conductivity ranges | 0 to 199.9µS/cm 200 to 1999µS/cm 2.00 to 19.99mS/cm |
| TDS ranges (Variable ratio) | 0 to 99.9ppm or mg/L 100 to 999ppm or mg/L 1.00 to 9.99ppt or g/L |
| Salinity range | 0 to 99.9ppm 100 to 999ppm 1.00 to 9.99ppt |
| TDS Ratio | 0.4 to 1.0 adjustable |
| Salinity Ratio | 0.4 to 0.6 automatic |
| Conductivity ATC | 2.0% per °C |
| Conductivity ATC Range | 32.0°F to 140°F (0.0°C to 60.0°C) |
| Temperature Range | 32.0°F to 149°F (0.0°C to 65.0°C) |
| Temperature Resolution | 0.1 up to 99.9 (1 > 100) |
| Temperature Accuracy | ±1.8°F (1.0°C) from 32 to 122°F (0 to 50°C) ±5.4°F (3.0°C) from 122 to 149°F (50 to 65°C) |
| Accuracy | Conductivity: ±2% full scale TDS: ±2% full scale Salinity: ±2% full scale |
| Measurement Memory | 25 tagged (numbered) readings |
| Low battery indication | BAT ? appears |
| Power | Four (4) CR2032 lithium-ion batteries |
| Auto power off | After 10 minutes of inactivity (override available) |
| Operating temperature | 23°F to 122°F (-5°C to 50°C) |
| Dimensions | 1.6 x 7.4 x 1.6 in. (40 x 187 x 40 mm) |
| Weight | 3.1 oz. (87 g) |
Warranty and Support
Two-year Warranty
Teledyne FLIR warrants this Extech brand instrument to be free of defects in parts and workmanship for two years from date of shipment. To view the full warranty text please visit: https://www.flir.com/support-center/warranty/instruments/extech-product-warranty/
Calibration and Repair Services
Teledyne FLIR offers calibration and repair services for the Extech brand products we sell. We offer NIST traceable calibration for most of our products.
Customer Support
- Local Telephone Support List: https://support.flir.com/contact
- Return Material Authorization (RMA): https://customer.flir.com/Home
- Customer Service: https://support.flir.com/ContactService
- Technical Support: https://support.flir.com
