Vernier Tech Info Library TIL #1361

pH Sensor Detail Information

pH Sensor, order code PH-BTA, $79.00
Specifications and User Guide

TROUBLESHOOTING
- Primary Test: Does it read approximately 4 in its storage solution? (pH 13-14 indicates 0 volts, possibly a defective sensor)
- Secondary Test: Take readings in fresh buffers NOT distilled water! If no buffers are available, try it in vinegar (~ pH 2.5-3.5) and ammonia (~ pH 10.5-11.5).
- V (amplified) for each buffer: pH 4 = 2.5 V, pH 5 = 2.25 V, pH 6 = 2 V, pH 7 = 1.75 V, pH 8 = 1.5 V, pH 9 = 1.25 V, pH 10 = 1.0 V (0.25 V/pH unit)
- mV (pre-amplified) for each buffer: pH 4 = 177 mV, pH 7 = 0 mV, pH 10 = -177 mV (59 mV/pH unit)

PUBLIC TIL ENTRIES
- TIL 1286: Why doesn‘t my pH Sensor read pH 7 in distilled or deionized water?
- TIL 728: How can I keep my pH or ORP storage solution from spilling when the sensor is in use?
- TIL 369: Where do I get pH Storage Solution? (Buffer Storage Solution)
- TIL 706: What is the best way to clean the glass bulb of the pH electrode?
- TIL 730: The pH electrode I have been using no longer seems to work. Is there anything I can do to fix it?
- TIL 1060: Do any of your sensors require special storage?
- TIL 782: The glass bulb of my pH Sensor is broken. Can it be repaired?
Public List of TIL Entries for PH-BTA

SPECIFICATIONS
- new order code: PH-BTA, 7120B + EA-BTA
- old order code: PH-DIN, 7120B + PHA-DIN
- Type: Sealed, gel-filled, epoxy body, Ag/AgCl internal reference, 12 mm OD
- Response time: 90% of full reading in 1 second
- Temperature range: 5 to 80 deg C
- 12-bit resolution: 0.005 pH units
- Smart Sensor as of 5/2000

CALIBRATION
- Calibrate? Usually no. Possible exceptions: water quality, Ka chemistry labs, or older pH sensors.
- as of 1/2005, PH-BTA is individually calibrated (each sensor has a unique factory slope and intercept)
- using Logger Pro, you can store your custom calibrations directly to PH-BTA sensor, by choosing Calibrate->pH from the Experiment menu, then pull-down Live Calibration and choose Calibration Storage. Click on Write Calibration to Sensor, and follow the on-screen instructions.

RELATED VERNIER PRODUCTS
- for buffers pH 4, 7, 10, pH Buffer Capsules, order code PHB, $12.00 (4 tablets each), add to 100 mL distilled water.
- pH Storage Solution, order code PH-SS, $15.00 (500 mL bottle)
- pH Storage Solution Bottles (5), order code BTL, $10.00 (5 bottles)

Created by: dholmquist on December 21 2004
Last updated by: jhopkins on December 28 2007