MKS MF1 - Start up the Mass Flow Controller;Meter; Zero Adjust

Chapter 3: Installation
24
Start Up the Mass Flow Controller/Meter
1. After you have successfully checked all mechanical and electrical connections and when
you are certain that there is no gas leakage, then power can be applied to the mass flow
controller or to the flow meter, respectively.
The first start up should be done preferably using a non-critical gas. This could be for
example nitrogen or dry air (if there are no reactive residuals in the plumbing system) or
any inert gas.
2. Switch on the power supply.
When power is first applied, the analog output signal will remain zero until the booting
process is finished (analog version)
The unit performs automatically a reset, indicated by green blinking of the status LED ST.
Finally the LED changes to green light which indicates that the unit is ready for use.
You can monitor the flow output signal as the instrument stabilizes and the output
approaches zero. Approximately 15 minutes after power up the signal should be stable
within some millivolts close to zero.
Note
Do not use dangerous gases for the first start up. Use a non-critical gas,
for example the gas which serves for purging.
Note
If the instrument is being used to control dangerous gases, be sure that
the system is fully warmed up before applying gases to the system. You
may choose to install a positive shutoff valve to prevent inadvertent gas
flow during the warm-up period.
Once the instrument is completely warmed up, you can proceed to zero the unit as
required.
Zero Adjust
1. If no gas is flowing and the mass flow controller has stabilized (ref. to Appendix A,
Specifications, Warm Up) the flow output signal can be zeroed. This can be done in two
different ways:
a) using the push button AUTOZERO, located at the gas inlet side of the unit. Use this
means only when gas flow is completely stopped. Check that the flow signal has been
set to zero!
b) Operation of these functions is also possible via one of the digital interfaces.
2. When using a control unit by MKS then you should use the zeroing means there. If the
control unit does not provide enough compensation range then the ZERO button at the
mass flow unit must be used.