Brooks Instrument 5851E - Manual (Page 18)

2-8
Brooks ® Model 5851E
Section 2 Installation Installation and Operation Manual
X-TMF-5851E-MFC-eng
Part Number: 541B104AAG
November, 2008
2-7 Soft Start
Refer to Figures 3-3, 3-4. To enable soft start, place the jumper on the
controller printed circuit board at J2 in the right hand (ss) position.
To disable soft start, place the jumper on the controller printed circuit board
at J2 in the left hand (n) position.
2-8 Remote Set-Point (Command) Input
If the mass flow controller is to be commanded by an external 0-5 Vdc
signal, the command potentiometer is not used.
The command input hookup is as follows:
A. Card Edge Connector
Connect the external command voltage to Terminal A, and external
command return to Terminal B. Refer to Figures 2-2 and 2-3.
B. D-Connector
Connect the external command voltage to Terminal 8 and external
command return to Terminal 1. Refer to Figure 2-4.
2-9 Valve Override
The valve override function allows full opening and closing of the valve
independent of the command setting. The unique command reset feature
prevents flow overshoot when the controller goes from valve override
closed to normal control.
The valve override for the mass flow controller is as follows:
a. To open the valve apply +15 Vdc to the valve override terminal.
b. To close the valve apply -15 Vdc to the valve override terminal.
c. Isolating the valve override terminal returns the controller to normal
operation.
A. Card Edge
The valve override function can be accessed from Terminal 9. Refer to
Figure 2-3.
Note: For normal operation Terminal 9 must be left open (floating).
B. D-Connector
The valve override function is accessed from Terminal 12. Refer to
Figure 2-4.
2-10 Remote Transducer Input
Refer to Figures 3-3 and 3-4. To allow the Model 5851E control circuitry
and valve to be used with an 0-5 Vdc external transducer signal, the
jumper at J7 is moved to the lower two pins (R). With this feature enabled
a 0-5 Vdc signal may be applied to the external transducer input terminal.
The Model 5851E controller circuitry will modulate the valve position to
increase or decrease the flow rate to maintain the transducer output at the