Bronkhorst Mass Flow - Manual (Page 17)

BRONKHORST HIGH-TECH B.V.
2.8 Electrical connections
Bronkhorst High-Tech B.V. recommends to use their standard cables. These cables have the right
connectors and if loose ends are used, these will be marked to prevent wrong connection.
Hook-up diagrams are enclosed in the back of this manual.
2.9 Caution
Each meter/controller is pressure tested to at least 1.5 times the working pressure of the process
conditions stipulated by the customer, with a minimum of 8 bar.
For pressure meter/controllers. The test pressure depends on the range of the pressure transducer.
In general 2 x F.S. value for ranges 1 and 2 bar
1.5 x F.S. value for ranges up to 200 bar
1.25 x F.S. value for ranges up to 400 bar
The tested pressure is stated on the flow meter/controller with a RED COLOURED sticker. Check test
pressure before installing in the line.
If the sticker is not available or the test pressure is incorrect, the instrument should not be mounted in the
process line and be returned to the factory.
Each instrument is helium leak tested to at least 2⋅10 -9 mbar l/s Helium.
2.10 Supply pressure
Do not apply pressure until electrical connections are made. When applying pressure to the system, take
care to avoid pressure shocks in the system and increase pressure gradually, especially on high pressure
units incorporating a piston operated control valve.
2.11 System purging
If explosive gases are to be used, purge the process with inert dry gas like Nitrogen, Argon etc. for at
least 30 minutes.
In systems with corrosive or reactive fluids, purging with an inert gas is absolutely necessary, because if the
tubing has been exposed to air, introducing these fluids will tend to clog up or corrode the system due to a
chemical reaction with oxygen or moist air.
Complete purging is also required to remove such fluids from the system before exposing the system to air. It
is preferred not to expose the system to air, when working with these corrosive fluids.
2.12 Seals
Bronkhorst High-Tech B.V. has gathered a material compatibility chart from a number of sources believed to
be reliable.
However, it is a general guide only. Operating conditions may substantially change the accuracy of this
guide. Therefore there is no liability for damages accruing from the use of this guide.
The customers’ application will demand its own specific design or test evaluation for optimum reliability.
So check if the seals like O-rings, plunger and packing gland of capillary are correct for the process.
2.13 Equipment storage
The equipment should be stored in its original packing in a cupboard warehouse or similar. Care should be
taken not to subject the equipment to excessive temperatures or humidity.
9.17.001 page 17