The device performance is specified as follows:
Type | Specification |
---|---|
Optical design | UV/VIS/NIR photometer (tunable Czerny-Turner monochromator) with additional internal reference beam |
Light source |
|
Wavelength range | VC-D40: 190 to 750 nm VF-D40: 190 to 900 nm The tungsten lamp is recommended for wavelengths > 345 nm. |
Spectral bandwidth | typ. 6 nm at 254 nm |
Wavelength Accuracy | ± 1 nm |
Wavelength Repeatability | ± 0.1 nm |
Wavelength Calibration | Internal calibration with zero order of monochromator spectrum |
Wavelength Validation | Internal validation with holmium-oxide filter |
Signal channels | VC-D40: Up to 2 signal channels VF-D40: Up to 4 signal channels |
Reference channel | Reference beam with same wavelength as measurement beam |
Data collection rates
| Data collection rates under Chromeleon 7 data system. Other maximum data rates may be applicable under different data systems. Single-channel: VC-D40: Adjustable, 0.2 Hz– 125 Hz VF-D40: Adjustable, 0.2 Hz– 250 Hz Multi-channel |
Filter response times (in seconds) | 0s (no filter) to 20s |
Spectra scans | 5 scan speeds up to max. 100 nm/s |
Noise (Single-channel mode) | < ± 2.5 µAU, wavelength 254 nm, only deuterium lamp on < ± 5.0 µAU, wavelength 520 nm, only tungsten lamp turned on Standard flow cell with 1 mL/min HPLC-grade water, degassed, column in flow path, time constant: 2 seconds, data collection rate: 1 Hz All values reached within 60 minutes of warm-up (typical). |
Noise (Multi-channel mode) | <± 10.0 µAU (typical: <± 7.0 µAU), wavelengths: 254 nm and 280 nm, only deuterium lamp turned on <± 10.0 µAU (typical: <± 7.0 µAU), wavelengths: 450 nm and 520 nm, only tungsten lamp turned on Standard flow cell with 1 mL/min HPLC-grade water, degassed, column in flow path, time constant: 2 seconds, data collection rate: 1 Hz All values reached within 60 minutes of warm-up (typical). |
Drift | < 0.1 mAU/hour, wavelength: 254 nm, only deuterium lamp turned on < 0.1 mAU/hour, wavelength: 520 nm, only tungsten lamp turned on Standard flow cell with 1 mL/min HPLC-grade water, degassed, column in flow path, time constant: 2 seconds All values reached within 60 minutes of warm-up (typical). |
Linearity | < 5% at 2.5 AU (ASTM), wavelength: 272 nm, component: caffeine, only deuterium lamp turned on Standard flow cell |
USB communication | 1 USB port (USB 2.0, "B" type connector) 1 USB hub with 3 ports (USB 2.0, "A" type connectors) |
I/O Interface | 2 digital I/O ports |
System Interlink | 2 System Interlink ports (RJ45-8 connectors) |
Analog output | 2 analog outputs via optional plug-in expansion board to output absorption channels Resolution: 20 bit |
Control | Chromeleon 7 The device can be operated also with other data systems. For details, contact the Thermo Fisher Scientific sales organization. Keypad with 3 buttons for performing certain functions directly from the device |
Materials in the flow path | See the Specifications for the flow cells. NOTICE For information about the chemical resistance of materials refer to the technical literature. |
Safety features | Power-up check of optics, cooling fans, motors and electronics Leak detection and safe leak handling |
Good Laboratory Practice (GLP) features | Predictive Performance functions for scheduling maintenance procedures based on the actual operating and usage conditions of the device. This includes monitoring of lamp age, and lamp ignitions for UV and VIS lamp. All system parameters are logged in the Chromeleon Audit Trail. |
Temperature reference conditions for noise, drift and linearity specifications
For drift tests, ASTM requires that temperature changes stay below 2 °C/hour over a period of one hour. The drift specification above is based on these conditions. Larger changes in the ambient temperature will result in a larger drift.
For best performance, minimize the frequency and the amplitude of changes in the ambient temperature to 1 °C/hour.
Time constant and response time
According to ASTM E1657-98, the time constant is converted to the response time by multiplying by the factor 2.2 (i.e., response time = 2.2 x time constant).