Brooks Granville-Phillips Convectron 316 Series, Инструкция по эксплуатации

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MANUAL P/N 316005 REV: B 55
5.3.3 Manual Override
The six three-position switches on the front of the process control module allow override of the programmed
setpoints at any time. When moved to the right, the relay is activated. When moved to the left, the relay is
deactivated. When left in the center position, the relay is controlled automatically.
5.4 Process Control Theory of Operation
The process control module contains a dedicated microcontroller and a nonvolatile memory chip for storage
of the setpoints. Since data is read/written to this chip serially, it is necessary to store working copies of the
setpoints in internal RAM memory.
The microcontroller compares the setpoints with the pressure display data on the display bus and makes a
decision as to whether or not to activate a channel's relay. The manual override switches, when set to ON or
OFF position, take precedence over the microcontroller's decision.
5.5 Process Control Troubleshooting
The setpoints are read from non-volatile memory into RAM when the unit powers up. If a setpoint is found to
contain data which cannot be interpreted as a valid setpoint, it will be set to 0.
If Microprocessor LED (Figure 4-4) is illuminated or flashing, there is a circuit failure.
5.6 Process Control Specifications
Number of channels 2 or 6
Pressure range 1.0 x 10
-5
to 9.9 x 10
+5
. Setpoints are compared directly to
display data and must be reprogrammed if the measurement
units, Torr, mbar, or pascal, are changed.
Hysteresis Approximately 10%
Setpoint adjustment Digital, 2 significant digits plus exponent, scientific notation
Output relays
Contact rating
Contact style
5 A at 250 Vac resistive or 30 Vdc
SPDT
Polarity Switch selectable for activation with pressure above or below the
setpoint. The factory setting is for activation below the setpoint.