F.A.Q.
SONIMIX 2106 vs SONIMIX 7000
What is the difference between both devices?
The SONIMIX 2106 is a gas divider using “Sonic Nozzles” and the SONIMIX 7000 is using the
Mass Flow controllers to generate the mixture.
What is a “Sonic Nozzle”?
A sonic Nozzle is a convergent-divergent hole with following properties: The flow through the
Nozzle is proportional to the absolute inlet pressure (Pin) and do not depends on the outlet
pressure (Pout) as long as Pout < Pin/2. This means that the flow of the sonic Nozzles is not
influenced by pressure atmospheric changes!
What is the accuracy of both devices?
The SONIMIX 2106 is the most accurate: 0.6% relative. The SONIMX 7000 has an uncertainty
of only 1.5% relative.
Why is the SONIMIX 2106 so accurate?
This is due to the technology of the sonic nozzles and high precision pressure regulator (+/-2
mbar). The pure mechanical process is not electronically regulated.
Why are your pressure regulators so good?
All the materials in contact of the gas are in Stainless steel of the best quality (and gold plate,
if the corrosive gas option is purchased). No plastic inside. No leakage.
What do you mean by “relative accuracy” and “absolute accuracy”?
There are 2 types of accuracy: Full Scale (or absolute) and relative. As example: If you have a
range of 5 to 50 L/min and uncertainty is 1%
Uncertainty on 50L/min
Uncertainty on 10L/min
Uncertainty on 5L/min
Full Scale (1%)
50 +/- 0.5 (= 1% relative)
10 +/- 0.5 (= 5% relative)
5 +/- 0.5 (= 10% relative!)
Relative
50 +/- 0.5
10 +/- 0.1
5 +/- 0.05
As you can see if the Uncertainty is given as absolute or Full scale, this one is the same of the
relative accuracy for the highest flow value, but much more higher in the lower flow rates.
Do I have to make some calculations?
No, the SONIMIX devices do calculate the end concentration in function of the cylinder
concentration, nature of the gas and selected dilution ratio.
Frequently Asked Questions
What are the available ranges and dilution steps ?
The SONIMIX 2106 best sellers have a dilution range of 10% to 100% in 10% dilution steps or
1% to 100% in 1% steps or 0.1% to 100% in 1024 dilution steps. The SONIMIX 7000 have
equivalents ranges, but with “almost continuous” steps. To increase the dilution range, a predivider can be used.
How many sonic Nozzle or Mass flow controller do you use in the SONIMIX ?
For the SONIMIX 2106 the number of nozzles depends on the number of dilution steps
(Dilution steps = 2n where n is the number of Nozzle) with 4 Nozzles you can have a system
with 16 dilution steps and with 10 Nozzles you can have a system with 1024 dilution steps.
For the SONIMIX 7000 we have 2 MFC for dilution range 10% to 100%, 3 MFC for dilution
range 1% to 100% and 3 dilution range for dilution range 0.1% to 100%.
What is the flow range of each Mass Flow Controller?
Each MFC is used with a range of 10% to 100%. (It looks small compared with other devices
of the market, but remember that MFC uncertainty is given with Full Scale value and that the
uncertainty of the MFC under the 10% of the Full Scale becomes huge.
What are the available inlets pressures?
For both devices we request an inlet pressure of 3 bar+/-0.5 relative. As you can see the
accuracy of this pressure is not very important and can be set by the pressure reducer of the
cylinder of any simple pressure regulator. (Other pressure settings are available upon
request)
Why do you have a back pressure on the SONIMIX 2106?
In the past some users have not connected correctly the SONIMIX 2106 with analyzers,
making a restriction at the outlet and generating a big pressure at the outlet of the Nozzles.
With the backpressure regulator, the outlet pressure range of the SONIIMIX 2106 will be
larger (up to 1 bar relative) and the pressure at the Nozzle will be constant, increasing the
accuracy.
Do you have a pressure sensor in the gas dividers?
We do have one pressure sensor on each line of the SONIMIX 2106. These pressure sensors
are not used for regulation, but only to check if the inlet pressure is sufficient. The SONIMIX
7000 has no pressure sensor (by the way, it will recognize if the inlet pressure is not correct,
by measuring the return signal of the MFC).
How do you calibrate the gas dividers?
Even the gas dividers generates “concentrations”, we calibrate them through flow rates
measurement. Our laboratory is ISO 17025 accreditated for flow rate measurement. Then,
Frequently Asked Questions
we measure real concentration with specific analyzer as quality control. A certificate is
supplied with each device.
What is an accreditation ISO 17025 ?
The ISO 17025 calibration certificates are very important. We not only give in the certificate
the value of the flow rate and dilution ratio, but also the related uncertainty. In addition, our
uncertainty measurement and procedure are yearly checked by an external company. The
ISO 17025 calibration certificates are recognized worldwide through the Ilac/MRA agreement
(https://www.ilac.org/ilacarrangement.html)
What is the calibration frequency?
All depends on your process. In general we recommend a service and calibration every 12 to
18 months for the SONIMIX 2106 and every 6 to 9 months for the SONIMIX 7000. The
difference is due of the Mass Flow Controllers that are drifting and need more frequent
calibrations.
How can I be sure that my gas divider is mixing correctly between 2 calibrations ?
The SONIMIX 2106 can be purchased with an “AutoDiagnostic/AutoCal” option. With this
option, it is possible to check if: the pressure regulators are working correctly, the valves
opens correctly, the flow through a nozzle are correct. This option is patented and has been
developed in collaboration with the NPL (UK Physical National Laboratory)
How many gases can I mix with a SONIMIX ?
The SONIMIX 2106 and 70002L are binary mixers. That means they can mix only 2 cylinders
(a diluted gas together with a balance or carrier) together. For interference measurement
you should select the SONIMIX 7000 Multigas, which is able to mix up to 6 different cylinders
at the same time.
Can I use multi-components gas cylinders?
Yes, both Sonimix support multi-component cylinders. The SONIMIX 2106 trough it’s LCD
interface and the SONIMIX 7000 through the GasCal PC software do accept up to 6
component per cylinder.
Can I use my SONIMIX with corrosive gases?
The SONIMIX 2106 has a specially designed option (special purge and rinse process and gold
plated material) to care about corrosive gases.
What is the highest and lowest gas cylinder concentration I can use?
For a pure mechanical point of view, there is no limitation. But if the cylinder concentration is
lower than 100 ppb, then some adsorption may be visible and longer stabilization time will
be necessary. For high concentration, the corrosive aspect of the gas needs to be considered.
Frequently Asked Questions
What is the option “Inlet Multiplexers”?
This option is used if you want to automate your process. The gas divider will choose 1 inlet
upon 4 (or 8 or 12 depending of the device). Without this option, if you want to mix another
gas, you have to remove the old cylinder and replace it with the new one.
How can I automate my process of mixing gases?
The SONIMIX 2106 has a specific menu where through a scenario, different steps where the
cylinder, the final concentration, and duration of the mixture can be programmed. For the
other products, the scenario can be generated through the GasCal PC software.
What are the benefit of a SONIMIX Gas Divider?
The automatisation is one of the advantages. Money and place saving together with return
of investment are certainly the most important one: to linearize (in 5 points) one multigaz
analyzer (5 different components) you should use 26 gas cylinders. With a SONIMIX 6
cylinder are sufficient.
Frequently Asked Questions