Colorimeter Module And Holding Coil; Rotary Valve Module; Mixer Module; Plumbing Diagram And Tubing Lengths - Hach APA 6000 Operation Manual

1.2.3 Colorimeter Module and Holding Coil

1.2.4 Rotary Valve Module

1.2.5 Mixer Module

1.2.6 Plumbing Diagram and Tubing Lengths

CAUTION
To familiarize yourself with
handling precautions, dangers
and emergency procedures,
always review the Material Safety
Data Sheets prior to handling
containers, reservoirs, and
delivery systems that contain
chemical reagents and standards.
Protective eye wear is always
recommended when contact with
chemicals is possible.
6202918overview.fm
Samples are measured in a temperature-controlled single-wavelength flow
cell. Light from an LED in the colorimeter passes through a 440 nm bandpass
filter. The path length is 8.75 mm (0.344 inches).The temperature is controlled
at 40 °C (104 °F).
The holding coil is a length of 0.030 inch ID Tefzel tubing arranged to minimize
mixing. The holding coil allows low volumes of representative sample to be
measured each cycle. The holding coil also effectively brings the sample and
reagents to the temperature control point. Without the holding coil, "old"
sample would need to be flushed from the burette. This would require at least
10x greater volume and longer analysis times, higher wastes, more sample
conditioning, additional standard consumption, etc.
The rotary valve directs fluids to various components in the instrument.
The valve is a selection valve with a common port at the center. An internal
rotor turns to align a groove between the center port and any one of the ten
available ports around the perimeter. The valve has a face-sealing design.
All tubing is factory-assembled and labeled for each individual chemistry.
The mixer module mixes reagents, sample, and standards. Fluid normally
enters and exits through the bottom of the module. The openings at the top
supply an overflow and a vent. The vent line is connected to the drain block.
The mixer is made of acrylic and has an approximate volume of 1.0 mL. The
mixer is filled, emptied, and rinsed during a typical measurement cycle. Mixing
and excess air removal is accomplished via a magnetic stir bar.
Figure 1 shows the user-replaceable tubing on the analyzer and
describes the terminal end sizes of each tube. The tubing is 0.030 inch ID
Tefzel. The small diameter allows for low-volume, high-flow rates. The higher
flow rate, along with properly applied sample conditioning, prevents the tubing
from plugging.
General information for replacing the tubing is presented in the APA 6000
Installation and Maintenance Manual (Cat. No. 62005-18).
PRUDENCE
Pour se familiariser avec les précautions à prendre lors de la manipulation, les
dangers et les procédures d'urgence, toujours lire les Fiches de Données de
Sécurité des Produits avant de manipuler les récipients, les réservoirs et les
systèmes de distribution contenant les réactifs chimiques et les solutions
étalons. Il est toujours recommandé de porter des lunettes de protection
lorsqu'un contact avec les produits chimiques est possible.
CUIDADO
Para familiarizarse con las precauciones de manipulación, los peligros y los
procedimientos de emergencia, siempre estudie las Hojas de Datos de
Seguridad de los Materiales antes de manipular recipientes, depósitos y
sistemas de entrega que contengan reactivos y patrones químicos. Siempre se
recomienda el uso de protectores oculares cuando sea posible el contacto con
productos químicos.
Section 1
Table 1
Page 7
General Description