Brooks Instrument 5851i - Manual (Page 18)

2-8
Installation and Operation Manual
X-TMF-5851i-MFC-eng
Part Number: 541B109AAG
September, 2009
Brooks ® Model 5851 i
Section 2 Installation
Chassis Ground
Connect earth ground to pin 14 of the D-connector.
Valve Override (connection optional)
The valve override function allows full opening and closing of the valve
independent of the setpoint:
To open the valve, apply +22.5 to +28 Vdc to pin 12
To close the valve, connect pin 12 to ground.
Isolating pin 12 (no connection) returns the controller to normal
operation.
NOTE: For normal operation, pin 12 must be left open (floating)
2-8 Configuring the PC Board
NOTE: To obtain access to the jumpers, the electronics cover can must be
removed. Disconnect the power to the mass flow controller and any cables
to the D-connector and the valve coil connector. Remove the three screws
at the base of the can and remove the top jack post of the D-connector.
Remove the can. The can must be replaced before returning the unit to
service. Refer to Section 2-6 for the proper electrical hook-up. Refer to
Figure 3-3 for PC Board jumper locations and functions.
Setpoint (Command) Input
The mass flow controller can be configured for voltage or current setpoint
(command) input. Jumper J7 (green) must be in the right-hand position for
0-5 Vdc setpoint and in the left-hand position for a 4-20 mAdc setpoint
input.
Signal Output
A 0-5 Vdc flow signal output is always available. The current signal output
is jumper selectable for either 0-20 mAdc or 4-20 mAdc. Jumpers J3 and
J4 (blue) must be in the upper position for 0-20 mAdc output and in the
lower position for 4-20 mAdc output.
NOTE: Both J3 and J4 must be in the same position. Jumpers J3 and J4
do not affect the voltage output.
Soft Start
To enable soft start, place Jumper J2 (red) in the right-hand position (SS).
To disable soft start, place jumper J2 in the left-hand position (N).