Waters 996 and 2996 PDA DetectorsCommands and Tips for Third-Party Devices
Waters 996 and 2996 PDA Detectors
Tip:
Before data acquisition can start, the detector needs some time to load the parameter settings. That is why a Wait command is required before data acquisition is started.
In addition to the standard commands, the Waters 996/2996 PDA detector driver supports the following commands and properties (please note that the display Filter level determines which commands and properties are displayed):
|
Property |
Min |
Max |
Description |
|
ExposureTime |
Auto; |
500 ms |
Time during which a single diode is exposed to light. (The value cannot exceed the Step value - see below.)
Do not change the default ('Auto') unless absolutely required. |
|
Interpolate656nm |
Off |
On |
On: To protect the photodiodes from over-saturation, the signal at 656.1 nm (Balmer line for deuterium) is ignored (visible only on the Expert level). |
|
Lamp |
Off |
On |
Turns the lamp on or off. |
UV Channel Commands
|
Property |
Min |
Max |
Default |
Description |
|
Off |
On |
On |
Allows signal averaging. |
|
|
1.2 nm |
30 nm |
1.2 nm |
|
|
|
Auto, 0.01 s |
4.80 s |
Auto |
Indicates the interval between two data points. (The value must exceed the ExposureTime value.) |
|
|
190 nm |
800 nm |
240.0 nm |
Indicates the wavelength at which the detector measures the signal. |
Tip:
After a Reset command, it takes 90 s until the detector is ready to execute further commands.
Commands and Properties of the 3D Field
|
Property |
Min |
Max |
Default |
Description |
|
1.2 nm |
60 nm |
1.2 nm |
Describes the bandwidth of a bunch of diodes. |
|
|
MaxWavelength |
MinWavelength |
799.6 nm |
799.6 nm |
Indicates the upper limit of the measuring range. (The setting cannot be changed during data acquisition.) |
|
MinWavelength |
190.0 nm |
MaxWavelength |
190.0 nm |
Indicates the lower limit of the measuring range. (The setting cannot be changed during data acquisition.) |
|
0.1 s |
0.1 s |
Indicates the interval between two data points. (The value must exceed the ExposureTime value.) |
||
Note:
Due to the minimum Bunch Width of 1.2 nm, the minimum and/or maximum wavelength can only have the following value: 190.0 nm + n*1.2 nm (where n = integer). If you enter a different value, the next lower value is used for the minimum wavelength and the next higher value is used for the maximum wavelength. This is logged in the Audit Trail.
Calibration Commands and Properties
The following commands and properties are provided for calibrating and validating the wavelength of the 996 and 2996 PDA detectors.
In addition, a dedicated sub-panel is provided in Chromeleon which can be used for validation and calibration of the wavelength. The sub-panel can be accessed in the Waters 996 / 2996 PDA section using the Calibration button provided on the Waters2690_996PDA.pan or Waters2790_996PDA.pan which are available in the Chromeleon Browser under Panels/LC_Other.
|
Property |
Description |
|
CalibrationMaxWl |
Specifies the center wavelength of the first diode in the array. On the calibration sub-panel of the 996/2996 PDA, the center wavelength of the first diode can be entered in the Array start box. |
|
CalibrationMinWl |
Specifies the center wavelength of the second diode in the array. On the calibration sub-panel of the 996/2996 PDA, the center wavelength of the second diode can be entered manually in the Array end box. |
|
WavelengthCal |
Starts calibration of the wavelength. |
|
WavelengthVal |
Starts validation of the wavelength. |
|
WlDeviation_A |
Reports the deviation of the first (D-alpha) calibration peak. |
|
WlDeviation_B |
Reports the deviation of the second (D-beta) calibration peak. |
The standard relay commands are available to control the relays of the Waters 996 and 2996 PDA detectors (refer to Practical Tips for Device Control 
Relay, TTL, and Remote Input Commands).
For information about how to install the Waters 996 and 2996 PDA detectors, refer to Hardware Installation 
Waters 996 and 2996 PDA Detectors: Installation.