Thermo Fisher Scientific Alpha pH 550 - Manual (Page 26)

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CAL
HOLD
ENT
CAL mV
READY
HOLD
CAL mV
HOLD
MEAS
°C
ATC
READY ENT
1 2 3 4
READY
R.mV
1 1
From ORP measurement mode press CAL key to enter calibration mode
as described in section 4.2. The LCD shows ‘CAL OrP’. Press ENT key to
begin calibration.
2
Place the electrode in a standard ORP solution of known OPR value.
Immerse the temperature probe in the buffer solution if ATC mode is
enabled. Immerse the potential matching pin in the buffer if symmetrical
mode is enabled. The buffer annunciator & electrode annunciator
appear in LCD. The upper display shows the current mV output of the
electrode with offset adjustment (if any). The lower display shows the
default (uncalibrated) mV output of the electrode. Allow the reading to
stabilize. LCD shows ‘READY’ annunciator when the reading is stable.
Press
▲ or ▼ key to set the upper display value to the ORP value of the
solution. Allowable range: -150mV to 150mV.
3
Press ENT key to confirm the value.
4
The pH Monitor reverts to ORP measurement mode.
4.5 Temperature Calibration
Calibrate temperature probe only if temperature value displayed on the pH Monitor
is different from that of a calibrated thermometer. Refer to section 5.3 for further
information temperature settings.