The yeast or particle is suspended in the chamber and light scatters
off the particles and simultaneously is read at three different
angles--forward scatter, 90°, and direct. The lower "gain" of the
forward scatter effectively precludes the measurement of particles smaller
than 1 micron; whereas the 0.5 micron protein suspended particles as well
as the yeast size particles are seen by the 90° scatter angle. The
comparison of the two angles will highlight what otherwise would not be
identified (the 0.1) to 1 micron protein particle).
This unit is manufactured at McNab, whose analyzers are well-known. One
of the design goals was to have a laboratory DLB "match" the
optics of the across-the pipe instruments.
This dual-angle instrument is a quad-head design - one head for the
light source, one for the background suppression, one for the 90° and one
for the forward scatter signal. This combined design with common
optics (specifically the illumination) eliminates the distortion error
otherwise occurring when comparing with two different sets of instruments.
This optical matching facilitates the user's ability to calculate the
shelf life of his sample.
Model DLB
|
Principle of Measurement: |
2-angle view geometry (forward and 90º)
optical scatter, ratio via a common reference signal, water-based. |
Range/Units: |
0-2.00, 0-20.00 EBC
0-2.00, 0-20.00 FTU
0-2.00, 0-20.00 NTU
0-20.00, 0-200.0 PPM as
SiO2 Custom range/units |
Accuracy: |
Typically:
+/- 0.04 or 2% on 0 - 2
scale.
+/- 0.40 or 2% on 0 - 20
scale
+/- 4.0 on 0 - 200 scale
Optional:
+/- 0.03 or 2% of reading
whichever is greater; on standard range, light, particle, bottle,
and calibration method.
|
Standard Deviation (typ.): |
Automatic (hue and intensity). When over
range, "Status 2" indicator flashes. |
Color Compensation: |
Automatic (hue and intensity). When over
range, "Status 2" indicator flashes. |
Measurement Type: |
1. Classic scatter
instrument (typ)
2. Electronically
enhanced for improved particle size suppression. |
Outputs (Optional): |
0 to 1 Ma, RS-232 |
Optical Lamp: |
370 - 2800 nm, tungsten filter adjusted
to green, white, red, or NIR to suit customer specifications. |
Measuring Chamber: |
SS 316L, glass optics |
Lamp Life: |
12 years (assuming 8 hours continuous
daily use). |
Sample Cell: |
Closed Style Optical
Quality:
2 - 1/4" Dia. x
4?1/2", 200 ml size
Open Style Optical
Quality:
62 mm Dia. x 150 mm 250
ml size.
Contact factory for other
sizes. |
Operating Temperature: |
22 - 150°F (-5 - 50°C). Use additives
when operating below freezing point of water. |
Power Requirements: |
115 or 220 VAC, 100 watts, 50 to 60Hz |
Correlation (typ): |
0.99 to DSB,
RS, &
HSB analyzers |
Calibrating Span Fluid: |
Formazin Primary Standard or PPM as SiO2 |
Calibrating Zero Water: |
Ultra-filtered laboratory grade (if
applicable) better than 0.1 NTU or 1/10th of Span value. |
Circulating Water: |
Supplied (or use supermarket bottled
water). |
Light Source: |
Polychromatic: (400 - 800 nm white
light, 370 - 2800 Tungsten) or
quasimonochromatic: red, Green, NIR, MEBAK |
Sensors: |
Dual ratio photodiode sensors |
Units: |
ASBC, EBC, NTU, PPM or custom |
Ranges (typical): |
0 to 10 (20) EBC
0 to l000 ASBC
0 to 200 PPM/DE
Automatic Switching |
Resolution: |
1 part in 2000 |
Bath: |
Water filled for cooling with chamber temperature measurement. |
Weight: |
50 lbs.(22.6 kg) |
Dimensions: |
10"h x 16" w x 25" d (25 x 40 x 63cm) in stainless steel
cabinet (316) |
Measuring Container: |
Chamber holder ID to match customer sample
bottle |
Display: |
Three bright 1/2 high digital LED displays. |
Operation: |
One-touch button control |
Color Rejection: |
Electronics Ratio Method |
Adjustments: |
Zero and span |
Fog Alarm: |
Condensation RH chemical indicator and electronics
flashing alarm |
Water Services: |
Rear inlet & output ports. Accepts 3/8"
(9.5 mm) inside diameter tubes. |
Circuit: |
Computer enhanced |
Accessories: |
On-line adapter sample kit
Rings for non-standard bottle
Sample various wet standards for calibration purposes
4000
NTU calibration standard
Sample cell open or closed
Rotating sample chamber
Calibration plot |
Meets CE requirements |