Varian ProStar 325 UV-Vis, Service Manual

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ProStar325 Service Manual
80
Publication date 8 May 2003
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Equipment name / Detector alias
The contents of the CMOS can be read and changed through user
software interface.
In order that the CMOS memory is not lost when the battery is
replaced, then replace the battery with the mains power on.
4.3.2.2 EEPROM
The EEPROM contains the following information ;
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Instrument serial number
•
MAC address
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Wavelength calibration factors, slope and offset
•
IP address
•
Gateway
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Lamp timer (on/off date and times)
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Detector installation date
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Last maintenance date
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Error log
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Dual Wavelength Configuration selection
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Extended Range Configuration selection
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Lamp Configuration
The contents of the EEPROM can be read and changed through
user software interface or by invoking the appropriate test
through the diagnostics thumbwheel selector switch (refer this
chapter and Diagnostics).
4.3.3 Signal processing and A to D conversion
Output signals from the Dual Photodiode Pre-amp PWB are fed
into the ANALOG INPUT circuitry. This circuit then performs a
number of functions;
Multiplexing between the two channels
buffering
level shifting
amplification
The signals are then sampled and held in preparation for the 16-
bit A/D conversion to take place.
4.3.4 Relay Outputs
There are 4 general purpose output relays and one dedicated
peak sense relay. Each output uses a DIP relay that is capable of
handling 500mA of contact current.
At reset or power up, the output relay contacts are set to the
default parameters. After loading a method they will be set as
defined in the methods T
0
parameters.
The peak sense relay is software programmable for duration,
delay and active sense. At power up the relay contact will be set
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