Thermo Fisher Scientific pHScan 3/3+ - Manual (Page 2)

Before You Begin
Remove electrode cap. To condition electrode,
immerse electrode in electrode solution, buffer
or tap water for at least 30 minutes. DO NOT use
deionized water
Calibration
Calibration should be done regularly, typically
everyday that the tester is used. You can calibrate
at up to three points (pH 4.01, 7.00 and 10.01
or 4.01, 6.86 and 9.18).
1. Press ON/OFF button to switch unit on.
2. Dip electrode about 2 to 3 cm into pH buffer
solution.
3. Press CAL button to enter Calibrate (CAL)
mode. ‘CAL’ flashes on the display. Then, a
pH value close to the pH buffer value will
flash repeatedly.
To abort calibration, press CAL again to
resume measuring mode.
4. After about 2 minutes when the
reading has stabilized, press the
HOLD/CON button to confirm
calibration. The display will show ‘CO’
and then switch to the buffer value
reading.
5. Repeat with other buffers if
necessary. Rinse electrode in tap
water before dipping into next buffer.
Insufficient sampling time. If
the tester does not have a long
enough exposure to the buffer, a stable
calibration point will not be reached.
Wait for about 2 minutes when the
reading has stabilized, press the
HOLD/CON.
Failure to re-hydrate the
electrode. A dry electrode will give
fluctuating readings while it
re-hydrates in a buffer, causing error.
68X247746 11/00 Rev 0
Buffer Set Selection
To choose USA (4.01, 7.00, 10.01) or NIST (4.01,
6.86, 9.18) buffers.
1. With tester off, hold HOLD/CON key while
pressing and releasing ON/OFF key.
2. The display will show “bUF” flashing.
3. Press HOLD/CON key. The display will show
either “USA” or “NST”.
4. Press CAL key to toggle between USA and NIST
buffer sets.
5. Press HOLD/CON key to confirm.
pH Testing
1. Remove cap from the electrode and press the
ON/OFF button to switch tester on.
2. Dip the electrode about 2 to 3 cm into the test
solution. Stir once and let the reading stabilize.
3. Note the pH or press HOLD/CON button to freeze
the reading. Press HOLD/CON again to release
the reading.
4. Press ON/OFF to turn off tester. If you do not
press a button for 8.5 minutes the tester will
automatically shut off to conserve batteries.
Reset To Factory Default
You can reset calibration data to factory default
settings. This is extremely useful when you want to
take a new set of pH measurements or when using
a new replacement electrode.
1. With tester off, hold CAL key while pressing ON/
OFF key.
2. The display will show “rSt” flashing.
3. Press HOLD/CON key to confirm. The display
will flash “YES” for 2 seconds and the tester will
go back to measurement mode.
4. To exit without confirmation, press CAL key. The
display will flash “NO” for 2 seconds and the
tester will go back to measurement mode.
WP pHScan 3 Instructions