Jenway 6300 Ser Man
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Pressing the CAL key again will enter this value into memory as the new
wavelength calibration offset.
Switch the unit off and then on again, allowing the Start Up tests to be
completed, re-check the certified wavelength calibration standard as
above and check that the reported value is now correct.
8.6
A to D Calibration
The A to D converter should only be calibrated by engineers who have
been trained on this aspect of servicing by Jenway Limited.
Equipment Required
; - A certified voltage calibrator with a resolution
of 0.1mV and a range up to at least +/-4.0000V.
A lead for connecting the calibrator to pins 1 (negative) and pin 3
(positive) of SK2 on the detector PCB. (8 pin Molex type connector)
Access the Detector PCB by removing the top case assembly as described
in Section 8.2 - Dismantling.
Remove the jumper from pins 3 and 4 on SK2 on the Detector PCB and
fit the lead connected to the calibrator.
Switch the calibrator on and select a negative output (or reverse the
contacts)
Select the A to D calibration mode by turning the unit on with the Print
key depressed.
The lower display will change to prompt for specific input levels and the
upper display will show the relevant mV output.
The initial prompt is for –1mV, set the calibrator to give an input signal
of –1mV, let the upper display settle and then press the enter key.
Then the prompt changes to –20mV, set the calibrator to –20mV let the
upper display settle and then press the enter key.
Continue responding to the prompts in this way for –39mV, -
200mV, -390mV, -2000mV and –3900mV. Note that the –39mV and –
