Brooks Instrument 5850E - Manual (Page 18)

Brooks ® Model 5850E
2-8
Installation and Operation Manual
X-TMF-5850E-MFC-eng
Part Number: 541B102AAG
September, 2009
Section 2 Installation
c. Isolating the valve override terminal returns the controller to normal
operation.
1. 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).
2. 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 5850E control circuitry
and valve to be used with a 0-5 Vdc external transducer signal, a green
jumper is moved to the lower two pins at J7. With this feature enabled, a 0-
5 Vdc signal may be applied to the external transducer input terminal. The
Model 5850E controller circuitry will modulate the valve position to increase
or decrease the flow rate to maintain the transducer output at the desired
set-point. The control circuitry is reverse acting, e.g., for an increase in
transducer output, the flow will correspondingly be decreased.
2-11 Valve Test Point/Purge
Refer to Figures 2-2, 2-3 and 2-4. The valve voltage can be monitored on
Pin D of the Card Edge version and Pin 7 of the D-Connector version. This
voltage relative to circuit common is proportional to the valve voltage per
the following equation:
Valve Voltage = (1.53 x TP3) + 20.7
( Note: The valve voltage calculation is an approximate value.)
Shorting the valve test point pin to power supply common will cause the
valve to open regardless of command input voltage.
2-12 Valve Off
Refer to Figures 2-2, 2-3 and 2-4. The control valve can be forced closed
regardless of command input signal by applying a TTL level low (< .4 Vdc)
to Terminal L of the Card Edge version or Pin 4 of the D-Connector
version. A TTL level high or floating at this pin has no effect.