User Manual ExStik® EC500 pH/Conductivity / TDS / Salinity / Temperature Meter Additional User Manual Translations available at www.extech.
Introduction Congratulations on your purchase of the ExStik ® EC500 pH/Conductivity/Total Dissolved Solids (TDS) / Salinity meter. With the EC500’s dynamic cell-constant technology it is possible to measure a wide range of Conductivity, TDS, and Salinity with the same electrode. Careful use and maintenance will provide years of reliable service. Powering the ExStik™ The ExStik® uses four (4) CR2032 Lithium Ion Batteries (included). If the batteries are weak, the ‘BAT’ indicator appears on the LCD.
Meter Description Front Panel Description 1. Battery compartment cover 2. LCD Display 3. MODE/HOLD button 4. CAL/RECALL button 5. ON/OFF button 6. Electrode Collar 7. pH/Conductivity Electrode (Note: The Electrode cap is not shown) LCD Display 1. Bargraph display 2. Measurement units 3. Main display 4. Range calibration and low battery indicators 5. Temperature display 6. Renew indicator 7. Reading hold indicator 3 EC500-en-GB_v2.
Measurement Procedure Sample Preparation: 1. For Conductivity, TDS or Salinity place the test sample in a sample cup with enough depth (2.5cm minimum) to cover the electrode. Stir the solution to remove any air bubbles. 2. For pH, place the tip of the electrode in the sample or make contact with a wet surface. Measurement: 1. Press the ON button. ( and then “SELF CAL” will appear in the display during the turn-on diagnostics) 2.
Changing Measurement Function The meter can be set to measure pH, Conductivity, TDS or Salinity. To change the mode: 1. Press and Hold the MODE/HOLD button for 2 seconds and the display will begin to scroll through the units. µS (Conductivity); pH; ppm S (Salinity); ppm (TDS); mg/l (TDS); Note: The “HOLD” function cannot be on when changing the measurement function. If “HOLD” is displayed in the lower left corner of the display, briefly press the MODE/HOLD button to turn it off. 2.
Recalling Stored Readings 1. 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. 2. The last stored reading will be displayed first. Pressing and releasing the MODE/HOLD button will scroll through the stored readings one at a time.
Calibration - pH (1, 2, or 3 points) 1. 6. Place the electrode into a buffer solution (4, 7, or 10). Press and hold the CAL/RECALL key until “CAL” appears in the lower (temp.) display. When doing a 2 or 3 point calibration, calibrate with pH 7 buffer first, then follow with pH 4 then the pH 10 buffer. The ExStik® automatically recognizes the solution and calibrates itself to that value (the circled number on the LCD will match the solution).
Calibration - Conductivity Meter accuracy verification should be performed on a periodic basis. Once per month is the recommended cycle for normal use. If calibration is required, a conductivity standardizing solution must be obtained. The meter can be calibrated in any or all of the three ranges. Standardizing solutions of 84µS/cm, 1413µS/cm or 12.88mS/cm (12,880µS/cm) are used for the automatic calibration recognition procedure. No other calibration values are permitted.
Operational Matrix Function / Resulting Action On/Off Power Status On or Off Mode Setting Required Key Press Sequence Any Momentary press of the ON/OFF key Calibration On pH or Conductivity Press & hold CAL/RECALL key for 2 seconds, until it enters CAL function Store Reading On Any measure mode Momentary press of the MODE/HOLD key Hold Release On While In Hold Mode Momentary press of the MODE/HOLD key Enter Memory Retrieval On Any measure mode Momentary press of the CAL/RECALL key follo
Specifications Display 2000 count LCD with Bargraph pH Range 0.00 to 14.00 pH Accuracy ±0.01 pH typical pH ATC Range 0°C to 90oC (32°F to 194oF) pH Reference Junction Permanent gel, non-refillable Conductivity ranges 0 to 199.9µS 200 to 1999µS 2.00 to 19.99mS TDS ranges 0 to 99.9ppm or mg/L (Variable ratio) 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.
Maintenance Battery Replacement 1. Twist off the battery compartment cap 2. Holding the battery housing in place with a finger, pull out the battery carrier using the two small tabs. Replace the four (4) CR2032 batteries observing polarity. Replace the battery compartment cap 3. 4. Never dispose of used batteries or rechargeable batteries in household waste.
Cleaning Recommendations When cleaning the probe, take care not to scratch or damage the sensing surface or the platinized electrode surfaces. Contaminant Cleaning Solution Instructions Water soluble substances Deionized water Soak or scrub with a soft brush. Recondition in 4 or 7 buffer for 1 hour. Grease & Oil Warm water and household detergent Soak or scrub with a soft brush, maximum of 10 minutes. Rinse thoroughly with DI water, recondition in 4 or 7 buffer for 1 hour.
Troubleshooting Problem Possible Cause Action Reading is frozen Unit is in “HOLD” mode Press MODE/HOLD key to exit “HOLD” mode “BAT” message Batteries are low Replace batteries Unit will not calibrate in pH Low pH slope Replace electrode, see reorder information Unit will not calibrate in pH Clogged or contaminated reference junction Clean junction (see cleaning instructions) Unit will not calibrate in pH Damaged or worn out sensing membrane Replace electrode, see reorder information Unit
