The measuring principle used in the HG - MONITOR 3000 is based on the resonance absorption of mercury atoms at a wavelength of 253.7 nm.
It exploits the high vapor pressure of mercury and the fact that except for
the noble gases, Mercury is the only element that has monoatomic vapor at room temperature.
The sample gas is continuously fed via a dust filter into the optical cuvette of the HG - MONITOR 3000.
Here an absorption measurement of the radiation emitted by a UV light source (253.7 nm Hg line) is carried out.
The intensity of the UV lamp is continuously measured via a reference beam and the measurement is corrected accordingly to compensate for possible fluctuations of the light source.
UV Light Source
The HG - MONITOR 3000's UV source is a low-pressure mercury discharge lamp with high-frequency excitation.
This method yields extreme-narrow-band emission lines, which are congruent with the absorption lines of the mercury atoms.
This provides improved detection sensitivity and a lower cross-sensitivity compared to other light sources. The lamp has a much longer service life than other UV lamps. The lamp unit is temperature-stabilized.
The HG - MONITOR 3000 is micro-processor-controlled. After it is switched on the device automatically calibrates itself and then switches to measuring mode. Inputs can be made via the waterproof membrane keyboard.
The following parameters are menu-adjustable:
- Display of ug/m3 or ppb
- Conversion to standard conditions
- Time interval for printer output
- Alarm level and prelim level
- 3 time intervals for computation of mean value
- Measuring range 0...20, 0...100, 0...1000, 0...2000 ug/m3 (ranges are user programmable)
Fields of Application
- Mercury in air
- Mercury in gases such as H2 , N2 and Natural Gas.
- Work-place monitoring
- 2 adjustable TLV (Threshold Limit Value) monitoring
- Measurement of mercury in exhaust air
- Ambient sir screening at ground level
- Detector for amalgam technology
- Continuous real-time online operation
- Easy to operate, self-explaining software
- Auto-zero for precise measurement
- Available for tabletop, 19" rackmount and mobile use
- Measurement range of 0.1 to 2000 µg/m3 (non-linear compensation in high measuring range )
- Temperature control for light-source and cuvette
- Unique electrodeless mercury lamp with long lifetime (over 20,000 hours)
- Wide range power supply (90 - 265 VAC/VDC, 12 VDC)
- Graphic TTF-display and one-touch keypad
- External Keyboard and VGA monitor, remote control by modem possible
- Approved for EMC and low-voltage directives (CE)
- Main component ("heart") of a complete range of mercury analysers for gases, liquids, solids
- RS 232 and 4-20 mA or 0-10 V analogue outputs
- Self-diagnosis, status outputs, printer port