Bronkhorst IN-FLOW - Manual (Page 28)

BRONKHORST HIGH-TECH B.V.
page 28 9.17.022
Note:
Special RS232 cable consists of a T-part with 1 male and 1 female sub-D 9 connector / 8DIN connector on
one instrument-side and a normal female sub-D 9 connector on the side of the computer. See hook-up
diagram for the correct RS232 cable which should be used.
By means of this cable it is possible to offer RS232 communication and still be able to connect power-supply
and analog interface through the (analog) sub-D 9 connector / 8DIN connector.
RS232 communication is only possible with a baudrate of 38.4 KBaud and can be used for either:
• Uploading new firmware by means of a special program (for trained BHT-service personnel only)
• Servicing your instrument using BHT-service programs (for trained BHT-service personnel only)
• Operating your instrument using FLOWDDE, FLOWB32.DLL or RS232-ASCII protocol (end user)
4 Maintenance
4.1 General
At normal use, no routine maintenance is required to be performed on the meters or controllers. Units may be
flushed with clean, dry inert gas.
For further information contact supplier or factory.
4.2 Gas flow sensor
The gasflow sensor is constructed in such a way that for a change in range, the laminar flow element can be
removed. It is not recommended for the user to disassemble the instrument other than for removing the
laminar flow element for inspection, or range changing only. After replacing the laminar flow element it
becomes necessary to recalibrate the flow meter. When doing so proceed according to a suitable calibration
procedure. Depending on the model number laminar flow elements can be ordered separately.
4.3 Liquid flow sensor
The user cannot change the flow range of a liquid flow sensor. The sensor is an integral part of the
instrument and cannot be removed from it. For occasional cleaning the instrument may be flushed with a
cleaning fluid.
4.4 Pressure sensor
It is not recommended for the user to disassemble the pressure sensor, because the thin metal membrane is
very delicate.
4.5 Controllers
All sensor types can be combined with a control valve to be operated together as a control loop. Controller
systems are either available as separate units; a sensor and a control valve, or as an integrated unit.
If applicable maintenance procedures are described under “control valves”
4.6 Control valves
Control valves cannot be used for shut-off and/or on-off applications. Pressure surges, as may occur during
system pressurisation or deflation must be avoided.