Bronkhorst®
Instruction Manual EL-FLOW® Classic series
9.17.085D
9
2.5
Inlet filter
Fluids to be measured should be absolutely free of dirt, oil, moisture and other
particles. Fluids that are heavily contaminated or contain particulates are detrimental
to precision. If liquid phases enter the sensor chamber, the function of the sensor and
the mass flow controller may be impaired. It is recommended to install an in-line filter
(offered by Bronkhorst) or liquid separator upstream of the flow controller, and if
backflow can occur, a downstream filter is recommended too. Be aware of the pressure
drop caused by the filter(s). Contact your distributor for further information.
2.6
Electrical connection
2.6.1
Interface
EL-FLOW® Classic
instruments are analog operated, I/O signals can be provided by means of:
1. Voltage I/O
(0...5Vdc)
2. Current I/O
(4...20mA sourcing)
For electrical hook-up diagram refer to the EL-FLOW® Classic
hook-up diagram
.
2.6.2
Power supply
EL-FLOW® Classic
controllers are powered with +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 that the source is capable of delivering enough power to the instrument(s). Refer to the EL-FLOW® Classic
hook-up diagram
, for more details.
The device contains electronic components that are susceptible to damage by
electrostatic discharge
. Proper handling
procedures must be followed during installation, (dis)connecting and removing the electronics.
The device described in this manual carries the CE-mark and is
compliant with the concerning EMC requirements
.
However, compliance with the EMC requirements is not possible without the use of proper cables and connector/gland
assemblies. Bronkhorst recommends the use of their standard cables. These cables have the right connectors and if loose
ends are used, these are marked to help prevent wrong connection. When using other cables, cable wire diameters should
be sufficient to carry the supply current, and voltage loss must be kept as low as possible. When in doubt, contact your local
Bronkhorst representative.
When connecting the product to other devices, be sure that the integrity of the shielding is not affected;
always use
shielded cabling for signals and communication and do not use unshielded wire terminals.
2.7
Powering up and powering down
·
It is recommended to turn on power before applying pressure and to switch off power after removing pressure.
·
For best performance, allow the device to warm up and stabilize for at least 30 minutes before starting measurement
and/or control. This may be done with or without media flow.
Be sure to apply the specified operating pressure(s). Avoid pressure shocks and bring the fluidic system gradually up to the
level of operating conditions; open and close the fluid supply gently.
2.8
Purging before use
In systems for use with corrosive, reactive or explosive media, purging the fluidic lines of the device for at least 30 minutes
with a dry, inert gas (like Nitrogen or Argon) is absolutely necessary before use. After use with these media, complete
purging is also required before exposing the system to air.
