Brooks Instrument 5851i - Manual (Page 15)

2-5
Installation and Operation Manual
X-TMF-5851i-MFC-eng
Part Number: 541B109AAG
September, 2009
Brooks ® Model 5851 i
Section 2 Installation
2-7 Electrical Interfacing
To insure proper operation, the 5851 i must be connected per Figures 2-2,
2-3 and 2-4 and configured according to Section 2-7. As a minimum, the
following connections must be made for new installations:
Function
Chassis Ground
Signal Output Return
Voltage or Current Signal Output
22.5-28 Vdc Supply
Supply Common
Voltage or Current Setpoint Input
Setpoint Return
Electrical Hook-up
Setpoint (Command) Input
The 5851i 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 pin 7 and the setpoint return (-) signal to pin 1 of the
D-connector and configure the PC Board per Section 2-7. To use the
voltage setpoint, connect the setpoint signal to pin 8 and the voltage
setpoint return to pin 1 of the D-connector and configure the PC Board per
Section 2-7.
(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.)
Figure 2-3 Maximum Allowable Loop Resistance