Hach BioTector B3500ul, User Manual

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Page 126
8.3.6 Reaction Check
CO2 LEVEL 100ppm, AUTO ▪
Due to the organic and inorganic contamination in the BioTector
reagents, every TOC/TC reaction will generate a small level of
CO
2
from the reagents alone even if there is no sample present.
The first setting (100ppm by default) of CO2 LEVEL specifies the
reaction check CO
2
level, which is the minimum expected CO
2
reading in ppm measured by the CO
2
Analyzer in a reaction.
▪ The second setting (AUTO by default) of CO2 LEVEL defines
the reaction check CO
2
level mode. When programmed as
AUTO, BioTector automatically sets the CO2 LEVEL to 60% of
the average CO
2
peak reading recorded during the Zero
Calibration or Zero Check reactions. If it is set as MAN (Manual),
system uses the fixed programmed CO2 LEVEL value.
▪
BioTector looks for first an increase and then a decrease in the
CO
2
peak data during the TOC phase (or TC phase depending
on ANALYSIS TYPE). If the CO
2
peak occur at the wrong phase
of the reaction and/or if the CO
2
peak is smaller than the
expected CO2 LEVEL (100ppm by default) for the number of
consecutive reactions defined by REACTION COUNT below (3
reactions by default), system generates a “ 04_REACTION
ERROR ” warning or a “ 04_REACTION ERROR ” fault
(depending on the FAULT TYPE setting below) and logs into the
fault archive.
▪
When CO2 LEVEL is programmed as 0ppm, the reaction check
function will be disabled. Reaction check function is omitted
during the zero calibration or zero check reactions.
FAULT TYPE WARNING ▪ FAULT TYPE determines the type (WARNING or FAULT) of the
“ 04_REACTION ERROR ” fault.
▪
When “ 04_REACTION ERROR ” fault occurs, if FAULT TYPE is
programmed as WARNING (by default), BioTector keeps
running. If it is programmed as FAULT, BioTector stops.
REACTION COUNT 3
▪
REACTION COUNT defines the number of consecutive
reactions (3 by default) before a “ 04_REACTION ERROR ” fault
is triggered.
TIC CHECK 2ppm
▪ TIC CHECK (2ppm CO
2
by default) represents the CO
2
check
point in the TIC phase. If the CO
2
level is above the programmed
check point at the end of the TIC phase, then the system
automatically extends the TIC SPARGE TIME by 1 second and
checks the CO
2
level again. If the TIC level does not drop below
the check point at the end of the maximum 300 seconds, a
“50_TIC OVERFLOW” warning is generated.
TOC CHECK 20ppm
▪ TOC CHECK (20ppm CO
2
by default) represents the CO
2
check
point in the TOC phase. If the CO
2
level is above the
programmed check point at the end of the TOC Oxidation
section of the TOC phase, then the system automatically
extends the TOC SPARGE TIME and TOC OXIDATION time by
1 second and checks the CO
2
level again. If the TOC level does
not drop below the check point at the end of the maximum 300
seconds, a “51_ TOC OVERFLOW” warning is generated.
TC CHECK 20ppm
▪ In TC and VOC systems, TC CHECK (20ppm CO
2
by default)
represents the CO
2
check point in the TC phase. If the CO
2
level
is above the programmed check point at the end of the TC
Oxidation section of the TC phase, then the system
automatically extends the TC SPARGE TIME and TC
OXIDATION time by 1 second and checks the CO
2
level again. If
the TC level does not drop below the check point at the end of
the maximum 300 seconds, a “ 91_TC OVERFLOW” warning is
generated.