Evoqua WALLACE & TIERNAN SFC, Original Instruction Manual

Page: 107 / 288

SFC
Functions
4.
107
4.12 CAN interface
The CAN interface is used as a CAN sensor bus and serves to
connect:
• CAN sensor measurement modules such as SiDiSens pH
The CAN interface of the SFC is electrically isolated. For the
purpose of connecting the CAN bus components, a standardised
plug connector (M12, 5-pin) is integrated in the SFC to supply the
CAN sensor with voltage.
For wiring, preassembled 4-wire cables of up to 10 m, a T-piece
and a plug with terminating resistance are available.
For longer cables the CAN bus cable 2 x 2 x 0.22 mm² and ready
to assemble plug connectors can be used (see spare parts).
The maximum cable length must not exceed 1000 m. Stub cables
should be avoided and are only permitted up to a total length of 5
metres.
The SFC operates as a master in the bus system. CAN slaves are
the attached sensors.
Please note
There can only be one master in the CAN bus system.
For this reason do not connect two SFCs together for data
exchange via the CAN interface.
Only the CAN sensor measurement module SiDiSens pH can be
used for the Cl
2
++ measurement (pH compensated Cl
2
measurement).
The combined chlorine in the SFC total chlorine can be measured
using CAN and a SiDiSens DES or via mA input 1 and a SFC for
the measurement of the free chlorine (see 4.2.9"mA inputs of the
A&C boards").