YOKOGAWA FC400G

< 1. Overview >
1-2
IM 12F5A1-01E
1.1 CongurationoftheFreeAvailableChlorine
Analyzer
The FC400G free available chlorine analyzer is broadly divided into a free available chlorine analyzer
main body (FC400G) and a sampling system: The main body consists of a detector and converter,
and the sampling system consists of sample water piping and a needle valve.
<FreeAvailableChlorineAnalyzerMainBody>
The detector consists of a measuring tank and electrode mechanism block. The detector
electrolytically reduces free available chlorine in the sample water supplied to the measuring tank to
obtainadi󰀨usioncurrentintheplateauregion.Italsogeneratessignalsforautomatictemperature
compensationofthisdi󰀨usioncurrentthatvarieswithtemperature.Themeasuringtankismade
of acrylic resin and contains ceramic beads in the part where a indicator electrode is inserted, for
polishing the electrode.
The electrode mechanism block incorporates an indicator electrode ( rotating electrode ), counter
electrode(Pt1000ΩRTD-built-insilverchlorideelectrode),anddrivingmechanismconsistingofa
synchronous motor that rotates the indicator electrode at a constant speed, and a belt.
Theconverter'smeasuringcircuitishousedtogetherwithanoperationpanelandexternalwiring
connectionterminalboardinaclosedaluminumcasing.Thismeasuringcircuitperformsamplication
and computation based on two signals from the detector to generate an output signal of 1 to 5 V DC or
4 to 20 mA DC corresponding to the output range.
<SamplingSystem>
TheFC400Gsampleinletshouldhaveapressureof1to150kPaaowrateof0.1to2.5l/min.
Samplemeetingtheseconditionscanbedirectlyintroducedtothemeasuringtank.However,
measurement of sample not meeting such conditions requires installation of a sampling system to
supply the required conditions.
YOKOGAWA's dedicated sampling system (ST401G) allows measurement of sample with a pressure
of100to750kPaandowrateof0.1to10l/min.