MKS PR 4000 F, Инструкция по эксплуатации

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PR4000F Chapter 4: Operation
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SCL
(only SLAVE or EXTRN )
:
The value of
SCL
(Scaler) determines the ratio of the setpoint which will be applied to the slave.
Example for two mass flow controllers:
Channel 1: MFC 500 sccm full scale, Mode Independent . This is the master channel!
Channel 2: MFC 200 sccm full scale, Mode Slave .
Scaler SCL set to 080.00 sccm.
When the master’s flow readout ranges from 0 –500 sccm the setpoint applied to the slave
ranges proportionally from 0 – 80 sccm ! The gas mixing ratio therefore is set to:
500 : 80 = 6,25 : 1
Example as before but for external setpoint mode EXTRN :
Channel 1: MFC 500 sccm full scale, Mode EXTRN (this makes channel 1 to be the „slave“ of the
external setpoint source!
Scaler SCL set to 350.00 sccm.
This means that the external setpoint applied to channel 1 will be scaled down by a factor of
350 : 500 = 0,7.
Depending on configuration and operational mode it is possible to have the setpoint input(s)
displayed. This however is possible only in the
INDEP mode.
For optimum control performance it is advised not to set the scaler to values below 20 % off the
MFC. It is possible but you should instead use MFC’s with lower ranges.
Note The setting of the scaler does not affect the independence mode INDEP !