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Figure A3.4 An example of BioTector 4-20mA output signals in Full Multiplex Mode
In the first step, the Stream ID channel is set to CHANGE level and 4-20mA READ relay is deactivated. After
a programmed time period, the first result type, TIC result, is indicated on the Result Type channel and
Instantaneous/Average Result Value channels are updated with TIC result from STREAM 1 valve. If the result
is unknown then 0.0 value is used. Then the Stream ID channel is set to indicate STREAM 1 valve. After 1
second delay, when all output channels stabilized their values, the 4-20mA READ relay is activated. Again,
this setting is hold for a programmed time period. Then Stream ID channel is set to CHANGE level and 4-
20mA READ relay is deactivated for a programmed time period.
In the next step, the reaction Result Type channel is set to next result type, TOC result, while the Stream ID
channel is still set to indicate STREAM 1 valve. Then TOC Result Value channels are updated and the
sequence continues in the same way as for TIC result until all relevant measured reaction results for
STREAM 1 are signaled out.
Finally, above steps are repeated for STREAM 2 and all programmed stream valves in the system. Similar to
the Stream Multiplex Mode, there is a need for some sort of synchronization between BioTector and the user
device (Stream ID channel or 4-20mA READ relay), since the 4-20mA output channels change on periodical
basis. If the Stream ID channel synchronization is used, the user device has to sample the Stream ID channel
and search for signal stable condition before reading the Stream ID and the reaction Result Value channels.
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