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1 prepare instruments for diagnostic test, 2 perform display test, 4 diagnosis steps diagnosis steps – Metrohm 784 KFP Titrino User Manual

Page 104

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4.2 Diagnosis

784 KFP Titrino

101

4.2.3 Equipment required:

Equipment required:

− voltage calibrator,

e.g. 1.642.0010 Metrohm pH Simulator

or 1.767.0010 Calibrated Reference for mV, pH, ê æS, °C

− highly insulated interconnection cable

6.2108.060

− resistor switch-box, class 0.1 % (or resistor 14.3 k, 0.1 %)
− cable 3.496.5070
− exchange units, if possible with different cylinder volumes (or 3.496.0070 dummy exchange unit)
− stop watch or watch with second hand
− digital or analogue voltmeter (if need be, connect a calibrated recorder)
− 2 connecting cables with 4 mm banana plugs
− test plug 3.496.8550 (necessary only if plug ‘Remote’ should be checked)
− test plug 3.496.8560 (necessary only if plug ‘RS 232’ should be checked)

4.2.4 Diagnosis steps

Diagnosis steps

1 Prepare instruments for diagnostic test

Power off.

Disconnect all external connections (cables at rear, except mains cable and keyboard).

Remove exchange unit.

Power on and immediately press and hold the <9> key until the powerup test pattern disap-

pears.

diagnose press key 0...9

2 Perform display test

Press <2>.

display test

Press .

Characters for a visual check of the display are generated on the eight lines.

Test sequence:

a) The display is cleared and overwritten from the top left to the bottom right with a dot

pattern ( ²²²²²²²² ).

b) The display is cleared and overwritten from the top left to the bottom right with a dot

pattern( °°°°°°°° ).

c) The display is continuously cleared and overwritten from the top left to the bottom

right with the complete character set. At the same time with moving display the

LED’s „COND.“, „STATISTICS“ and „SILO“ are switches on and off.

The test sequence can be held and then continued at any time by pressing <5>.

Block 2 is quit by pressing .

diagnose press key 0...9