Brooks Instrument Mfi Series - Manual (Page 26)

2-8
Brooks ® Mf Series
Section 2 Installation Installation and Operation Manual
X-TMF-Mfi-Mfx-eng
Part Number: 541B074AAG
August, 2009
2-10 Electrical Interfacing (Electrical Specifications Refer to Section 1-5)
To insure proper operation, the Mf device must be connected per Figures
Figure 1-2 (Maximum Allowable Loop Resistance); Figure 1-3 and Table 1-3
(Terminal Strip Hookup); and Figures1-7 through 1-12 (Dimension
Drawings). Configure in accordance to Section 2-9 and Figure 3-5. As a
minimum, the following connections must be made for new installations:
Chassis Ground
Signal Output Common
Voltage or Current Signal Output
Plus (+) Vdc Supply
Supply Common
Voltage or Current Setpoint Input
Setpoint Common
Setpoint (Command) Input
The Mf Series Mass Flow Controller can be used with a current (4-20 mAdc)
or voltage (0-5 Vdc) setpoint. To use the current setpoint, connect the
setpoint (+) signal to TB-2, Terminal 9, and the setpoint return (-) signal to
TB-2, Terminal 7, and configure the PC board per Section 2-7. To use the
voltage setpoint, connect the setpoint signal to TB-2, Terminal 8, and the
voltage setpoint return to TB-2, Terminal 7, and configure the PC board per
Section 2-7 and Figure 3-5.
(The Brook’s MFC acts as a current sink to a setpoint input signal. The 0/4-
20 mA setpoint signal should be “driven” into the MFC input by a controlled
current source. Reference Brook’s device specifications for the setpoint
input impedance.)
Signal Output
The flow signal output can be measured as a voltage or a current
simultaneously on two different positions of the Terminal Strip, TB-1,
Terminal 5 indicates the flowrate with a 0-5 Vdc signal proportional to the
mass flow rate. TB-1, Terminal 6 indicates the flowrate with either a
0-20 mAdc or 4-20 mAdc current signal as determined by jumpers on the
PC board (refer to Section 2-7 and Figure 3-5 for jumper positions). Both
the current and voltage signals are returned on TB-1, Terminal 4.
(The Brook’s MFC acts as the current source when providing a 0/4-20 mA
output signal to the load. The output signal is “driven” by the MFC into the
customer load. Reference Brook’s device specifications for maximum load
capacity.)
Supply
The power for the mass flow controller is connected to TB-1, Terminal
1 (+ Supply Voltage, Table 1-4) and TB-1, Terminal 2 (supply common)
of the terminal strip connector. Refer to Section 1-3 for power
requirements.
Note: The length of wire for the power supply connections (TB-1, Terminals
1 and 2) must be kept as short as possible to insure the minimum required
voltage is available at the mass flow controller.