Watts LF007 Serie Instrucciones De Instalación página 3

The IOT models of Series LF007 and LF709 double check valve backflow preventers include
integrated sensors on test cocks No. 2, No. 3, and No. 4 to measure pressure fluctuations
at the three locations. Pressure measurements allow assessment of the performance of the
backflow preventer assembly.
The monitoring connection kit interfaces with both the pressure sensors on the valve assembly and
the BMS controller, using an interface module that inputs DC voltage signals and outputs digital
data values compatible with the Modbus RTU protocol. The module converts data at the rate of up
to 25 conversions per second and stores the latest result in a buffer. The host processor requests
data values by sending a Modbus query to the module, and the module responds in real
time by communicating the memory buffer data values to the host processor. The module
communication settings are stored in nonvolatile EEPROM (Electrically Erasable Programmable
Read Only Memory), ensuring the settings are maintained if power is lost or removed.
The module can be configured with most any Modbus master program or with the utility
software described in the appendix.
The illustration shows the flow of communication between the kit and the monitoring workstation
(host processor) using the Modbus RTU protocol. The host processor sends a query to the
module requesting data values, and the module responds immediately by communicating the
latest set of stored values to the host processor.
Backflow preventer with pressure sensors
affixed to test cocks No. 2, No. 3, No. 4
BMS Monitoring Connection Kit
Building Management System
Monitoring workstation/host processor
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