Bronkhorst LIQUI-FLOW L30 - Manual (Page 13)

BRONKHORST HIGH-TECH B.V.
9.17.044 page 13
3 OPERATION
3.1 General
The Bronkhorst High-Tech B.V. instruments are designed in such a way that they will meet user process
requirements in the best possible way.
The LIQUI-FLOW L30 meters/controllers can be powered from +15 Vdc to +24 Vdc.
When providing your own power supply be sure that voltage and current rating are according to the
specifications of the instrument(s) and furthermore that the source is capable of delivering enough power to
the instrument(s).
Cable wire diameters should be sufficient to carry the supply current and voltage losses must be kept as low
as possible. When in doubt: consult factory.
Caution: The LIQUI-FLOW L30 meters/controllers must be powered via the 8 pin circular connector. It
is not possible to power the instruments via the bus connector.
Digital instruments can be operated by means of:
1. Analog interface (0...5Vdc/0...10Vdc/0...20mA/4...20mA)
2. RS232 interface (connected to COM-port by means of special cable on 38400 Baud)
3. FLOW-BUS
4. PROFIBUS-DP
5. DeviceNet
6. Modbus (special request)
Option 1 and 2 are always present on multibus instruments. An interface to any available fieldbus is optional.
Operation via analog interface, RS232 interface and an optional fieldbus can be performed at the same time.
A special parameter called “control mode” indicates to which setpoint the controller should listen: analog or
digital (via fieldbus or RS232). The RS232 interface behaves like a FLOW-BUS interface.
When using more interfaces at the same time, reading can be done simultaneously without problems.
When changing a parameter value, the last value send by an interface will be valid.
Also the push-button switch and the LED’s on the back side of the instrument can be used for manual
operation of some options.
The green LED will indicate in what mode the instrument is active.
The red LED will indicate error/warning situations.
3.2 Power and warm-up
Before switching on power check if all connections have been made according to the hook-up diagram which
belongs to the instrument.
It is recommended to turn on power before applying pressure on the instrument and to switch off power after
removing pressure.
Check fluid connections and make sure there is no leakage. If needed purge the system with a proper fluid.
For a gas instrument only purging with gases is allowed. Liquid instruments may be purged with either a gas
or a liquid, whatever is needed for the purpose.
Turn on power and allow at least 30 minutes to warm up and stabilise. In cases where no electronics are
involved (valves only) warming up is not needed.
During warm-up period, fluid pressure may either be on or off.