Bronkhorst IQ+FLOW (from 01-07-2013) - Manual (Page 10)

Bronkhorst High-Tech B.V.
IQ+FLOW 9.17.045 10
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.