Bronkhorst EL-FLOW Prestige - Manual (Page 12)

Bronkhorst High-Tech B.V.
EL-FLOW Prestige 9.17.084 12
2.9 Zeroing (using micro switch)
The zero-point of each instrument is factory adjusted. If so required the zero point may be re-adjusted over RS232, fieldbus or by
means of using the micro switch. Procedure for zeroing by micro switch (for zeroing through a command via BUS/RS232 see section
3.9.5):
1. Warm-up, pressure up the system and fill the instrument according to the process conditions.
2. Make sure no flow is going through the instrument by closing valves near the instrument.
3. The setpoint must be zero.
4. Press micro switch and hold it. After a short time the red LED will go ON and OFF, then the green LED will go ON. At that
moment (which is 8...12 s after pressing) release the switch.
5. The zeroing procedure will start at that moment and the green LED will blink fast. The procedure will take approx. 5 seconds.
6. When the indication is showing 0% signal and the green indication LED is burning continuously again, then the zeroing action
was successful.
2.10 Purging
Do not apply pressure until electrical connections are made. When applying pressure to the system, avoid pressure
shocks in the system and increase pressure gradually. Also decrease pressure gradually when required.
In systems for use with corrosive or reactive fluids, purging for at least 30 minutes with a dry, inert gas (like Nitrogen
or Argon) is absolutely necessary before use. After use with corrosive or reactive fluids, complete purging is also
required before exposing the system to air.
Let the EL-FLOW Prestige warm-up for at least 30 minutes for best accuracy.
2.11 Supply pressure
It is recommended to turn on power before applying pressure on the instrument and to switch off power after
removing pressure. Turn on fluid supply gently. Avoid pressure shocks and bring the instrument gradually up to the
level of the actual operating conditions. Also switch off fluid supply gently.
2.12 Calibration
Each EL-FLOW Prestige instrument is factory calibrated. Bronkhorst High-Tech B.V. certifies that all instruments meet the rated
accuracy. Calibration is performed using measurement standards traceable to the Dutch Metrology Institute (VSL). Calibration
certificates are included in the shipment. Periodical inspection, recalibration or verification of the accuracy may be subject to
individual requirements of the end-user.
Unless specified otherwise, EL-FLOW Prestige instruments are N
2
calibrated. The calibration is converted to the
customer’s fluid and conditions using a detailed conversion model. This conversion model provides all the fluid data
and calculations for the applicable process conditions and is also used for the multi-gas/multi-range functionality of
the instrument.
2.13 Maintenance
No routine maintenance is required to be performed on the meters/controllers when they are used with clean gas, compatible with
the wetted materials in the instruments. Units may be flushed with clean, dry inert gas.
In case of severe contamination it may be required to clean the inside of the instrument. After cleaning a recalibration is needed.
Bronkhorst High-Tech B.V. has a trained staff available. Contact your local supplier for cleaning and recalibration options.
If the equipment is not properly serviced, serious personal injury and/or damage to the equipment could be the
result. It is therefore important that servicing is performed by trained and qualified personnel.