Flow-Bus; General; Technical Information - BRONKHORST FLOW-BUS Instruction Manual

2

FLOW-BUS

2.1 General

FLOW-BUS is a 3-wire, RS485-based fieldbus communication system for parameter value exchange between
digital BRONKHORST HIGH-TECH B.V. products.
In this system each instrument/device is equipped with a micro-controller for its own dedicated task but also for
exchanging parameter value information with other instruments/devices connected to the same FLOW-BUS
system.

2.2 Technical information

FLOW-BUS systems may have a minimum of 2 and a maximum of 126 connections.
The maximum length for datalines between the first and the last connection may be up to approx. 600 meters.
Longer distances are only possible in combination with special bus-repeater modules.
Each instrument/device connection T-part (stub) must be kept as short as possible (max. cable length 0.5
meter!).
The baudrate used to transport messages is 187.5 Kbaud.
FLOW-BUS is a multi-master network with a token-ring architecture.
3
FLOW-BUS
IN/OUT
1
Node 2
USERTAG AIR
10.00 ln/min
7.03.297
B
EGIN TERMINATOR
7.03.241
M Y-
ODULAR ADAPTER
Node 1
9.17.024
BRONKHORST HIGH-TECH B.V.
7.03.299
RJ45 Multi-port adaptor
EL-FLOW
mass flow meter/controller
FLOW-BUS
Node 3
EL-FLOW
mass flow meter/controller
FLOW-BUS
Node 4
EL-FLOW
mass flow meter/controller
FLOW-BUS
Node 5
EL-FLOW
mass flow meter/controller
FLOW-BUS
Node 6
PowerIsolator
1.09.239
EL-FLOW
mass flow meter/controller
FLOW-BUS
Node 7
3
EL-FLOW
mass flow meter /controller
FLOW-BUS
Node 8
7.03.299
RJ45 Multi-port adaptor
1.09.240
E
ND TERMINATOR
EL-FLOW
mass flow meter/controller
FLOW-BUS
Node 9
EL-FLOW
mass flow meter/controller
FLOW-BUS
Node 10
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