Advanced Instruments 3900, Руководство пользователя

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Press STOP to end a test. The display will revert to the title of the test
selected. Use the SETUP keypad to change to the SETUP program, the
> or < keypad to step to another test or STOP to simply exit the TEST
program.
Descriptions of the TEST menu items and instructions for their use fol-
low:
1. A/D Tests
This set of tests may be used to test the block probe, the cooling
assembly and the sample probe. The A/D tests may also be used to
check the accuracy of the A/D conversion channel or to monitor the
A/D channel for drift over time or temperature (by temporarily
replacing the sample probe with a precision resistor).
On entry, “
[START] Ready? ” is displayed. Pipet or measure 0.2 to
0.3-mL of 1500 mOsm standard into a sample tube and place the
tube in the first position in a cassette. Place the cassette in the left
(input) deck and press the START button.
When START is pressed, the A/D tests display the target cooling-
block temperature, the channel being read and the current channel
reading or duty cycle. The display is in the form, “ off Blk
NNNN.NN ohm ”, where “ off ” indicates that a target temperature
has not yet been selected, “ Blk ” indicates that the block probe chan-
nel is being tested, “ NNNN.NN ” is a numeric readout of the probe
(or resistor substituted for the probe), and “ ohm ” indicates the units
of the readout. These readings are updated continuously.
Pressing the < button sequentially changes the target cooling-well
block temperature from “ off ” to “ +1 ”, to “ -8 ”, to “ off ”, etc.
Pressing the > button sequentially changes the channel and readout
units from block-probe resistance in ohms, to sample-probe resis-
tance in ohms, to block temperature in tenths of a degree Celsius, to
sample temperature in tenths of a degree Celsius, to cooling block
duty cycle (“ NN% ” on), to block probe resistance in ohms, etc.
Troubleshooting & Service