Appendix 3.3 Full Multiplex Mode - Hach BioTector B7000 User Manual

Appendix 3.3
While 4-20mA Stream Multiplex Mode helps to eliminate most of hardware limits for multi-component
BioTector systems, the Full Multiplex Mode brings the multiplex concept one step further. The 4-20mA Full
Multiplex Mode allows outputting all possible system reaction results on all possible streams over only 3
output channels. This is carried out by using two multiplex output channels, which change over time on
periodical basis cycling through all programmed output options. The first one is the 4-20mA output channel,
dedicated to the indication of Stream ID information (e.g. Stream 1, 2, Manual 1, 2 etc. as in Stream Multiplex
Mode). The second one is the 4-20mA output channel, which is dedicated to indication of reaction component
result type (e.g. TIC, TOC, TN, etc.).
The output channel, which indicates the reaction result stream information, is called STREAM
IDENTIFICATION channel.
information is called RESULT TYPE channel. Finally, the output channels, which output either instantaneous
or average reaction results, are called INST / AVGR RESULT VALUE channels. Unlike the Direct Mode, in
Full Multiplex Mode, the output channels depend on each other and change over time in a periodical manner
as it is carried out in the Stream Multiplex Mode.
The whole Full Multiplex Mode output sequence can be described as follows:
1. 4-20mA READ output is deactivated, Stream ID channel is set to CHANGE value
2. wait programmed time delay (Signal Hold Time, default value 10s)
3. Result Type channel is set to M
4. Result Value channels (both instantaneous and average) are updated with N
5. Stream ID channel is set to indicate N
6. wait 1 second time delay
7. 4-20mA READ output is activated
8. wait programmed time delay (Signal Hold Time, default value 10s)
9. steps 1-8 are performed for all measured system reaction types M, if all carried out then continue with
step 10.
10. steps 1-9 are performed for all measured system streams N, if all carried out then continue with step
11.
11. 4-20mA READ output is deactivated
12. Stream ID channel is set to CHANGE value
13. reaction result type is set to NOT_DEF value
14. wait for a new result or programmed time (Update Period) and start with step 1.
An example of Full Multiplex sequence is shown in figure A3.4, where the system outputs TIC, TOC and TN
reaction results for stream 1 and stream 2.
Full Multiplex Mode
The output channel which indicates the reaction component result type
th
reaction type (e.g. TIC, TOC, TN, etc.)
th stream valve
th
stream reaction result
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