BRONKHORST HIGH-TECH B.V.
9.17.024
Page 11
2.5 Power
supply
Bronkhorst High-Tech uses FLOW-BUS cables with extra wires inside for +15 Vdc/+24 Vdc and 0 Vdc in
order to handle power supply and communication with the same cable.
Because RS485-cabling needs a daisy-chain connection and power-lines prefer a star-point connection, we
came to a compromise of both in the FLOW-BUS cabling.
Bronkhorst High-Tech can advise you how to power your FLOW-BUS system.
It is the best to keep the power-lines as short as possible, so local power-supply is preferred.
This of course, depends on your demands of building-up your system.
A rule of thumb:
Using standard power-supplies from Bronkhorst High-Tech B.V. and Shielded Twisted Pair patch-cable
with RJ45 connectors for non IP65 applications and DeviceNet cables with circular M12 connectors for IP65
applications:
A cluster of 4 digital controllers can be powered locally from a distance approx. <= 6.5 meters from the
power-supply.
Powering more instruments will reduce the distance allowed to the supply-unit in linear relationship.
2.6 Installation
All modules in a FLOW-BUS system must have their own address.
FLOW-BUS systems will not function properly when there are more modules on the same address.
To avoid this, modules will do a check before getting operational on their bus-address and give a message
when this address is occupied.
If you receive a complete FLOW-BUS system from Bronkhorst High-Tech all modules have been installed
to the bus already (in one system).
Each time you power-up your system afterwards, the modules will start-up on the same address on the bus,
because these settings are stored in their non-volatile memory.
So if you receive a new system, normally you only have to connect the cables and switch on the power.
If a new module has to be connected to a bus system, it needs a free address. Normally this will be the first free
address counted from address 3.
Address 0 is reserved for the start-up procedure. Address 1 is reserved for an interface module to (personal)
computers and address 2 has been reserved for operation modules like E-7000.
There are four ways to add a new module to your bus system:
2.6.1
Automatic installation to FLOW-BUS
Most FLOW-BUS modules have the facility to install themselves automatically on the bus. This means that they
are able to find the first free node-address counted from 3 and connect themselves to the bus. This action can be
started by means of a manual interface on the module. Directly afterwards the new module will be part of the
FLOW-BUS system. See manual 9.17.023.
Note: make sure to install only one new module at the same time.
2.6.2
Remote installation to FLOW-BUS
Some FLOW-BUS modules have to be installed on the bus by means of another FLOW-BUS module or a
(personal) computer. This can be done as follows:
- By means of the micro-switch on the instrument. See instruction manual 9.17.023.
- With a Readout/Control module, series E-7000/E-7001 or with a software program on the PC this new
module can be searched.
- The Readout/Control module or PC-program will find the first free node-address counted from
address 3 (3 is first free address).
- This free address number will be send to the new module, which should become active on this
address.
