Section 1 Introduction
Fast Response Performance
The curves in Figure 1-2 depict the MFC output signal and actual transitional
flow to steady-state when gas flow enters into process chamber, under a step
response command condition.
Brooks devices also feature adaptive (optimized) PID control, including fast
response. and linear ramp-up and/or ramp-down control characteristics.
Calibration Selection
Select one of 6 calibrations via Brooks Expert Support Tool (BEST) or digital
signal (See communications protocol for your digital coms). Analog devices
can be switched via voltage signals to Pin 11 & 8 on Firmware Version 1.18 &
newer.
Selectable Soft Start
Processes requiring injection of gases can be adversely affected by excessive
initial gas flow. This abrupt injection of gas can result in process damage from
explosion or initial pressure impact. These problems are virtually eliminated
with the soft start feature.
Linear ramp-up or ramp-up/down (Figure 1-3) is set by user via software tools
or digital commands.
Linear ramp-up/ramp-down is adjustable at 200% per second down to 0.5%
per second setpoint change.
Figure 1-1 General Wiring
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