Bronkhorst IQ+FLOW (till 01-07-2013) - Manual (Page 9)

9.17.045 page 9
Warm-up time
Let the IQ + FLOW® warm-up for at least 30 minutes for best accuracy.
2.10 Zeroing
The zero point of each instrument is factory adjusted. If required the zero point can be re-adjusted over
RS232 or by means of using the micro-switch. Procedure for zeroing by-micro switch (not for pressure
meter/controller):
- Warm-up, pressure up the system and fill the instrument according to the process conditions.
- Make sure no flow is going through the instrument by closing valves near the instrument.
- The setpoint must be zero.
- 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 release the micro-switch.
- The zeroing procedure will start at that moment and the green LED will blink fast. The zeroing
procedure waits for a stable signal and saves the zero. If the signal is not stable, zeroing will take
long and the nearest point to zero is accepted. The procedure will take approximately 10 seconds.
- When the indication is showing 0% signal and the green indication LED is burning continuously
again, the zeroing action was successful.
2.11 Calibration
Each IQ + FLOW® 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
standards of the Dutch Metrology Institute (VSL). Calibration certificates are included in the shipment.
When operated properly (clean gas, no pressure shocks, no vibrations, no thermal shocks, etc.), regular
maintenance is not required. However, periodical inspection, recalibration or verification of the
accuracy may be subject to individual requirements of the end-user.
2.12 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.