Convectron Ionization Gauge Controllers

Description

Granville - Phillips Model 475 for accurate low vacuum measurement

Series 475 Convectron gauges provide useful pressure measurement over 7 decades from 10^-4 to 1000 Torr, or from 1 x 10^-3 mbar to 1000 mbar. This innovation in the art of vacuum measurement is accomplished with a single gauge tube and controller. The Series 475 gauge tube contains a temperature compensated heat loss sensor which utilizes conduction cooling to sense pressure at lower pressures. At higher pressures, it utilizes convection cooling in which gas molecules are circulated through the gauge tube by gravitational force.

Their wide useful range, highly predictable performance and low prices make Convectron gauges an excellent replacement for conventional thermocouple and Pirani gauges. They also are the measurement systems to consider in applications where conventional thermocouple and Pirani gauges have not been suitable because of limited range, or drift, or slow response.

Convectron gauges may be considered for use in certain applications where more expensive gauges such as capacitance manometers would be the first choice were it not for their higher cost.

Convenience and Versatility

The Convectron gauge is designed to give "plug-in-and-read" convenience. No pre-installation calibration is required because it is computer calibrated prior to shipment. It snaps into an instrument panel cutout without tools or hardware.

Convectron gauges offer the following advantages relative to thermocouple gauges:

• System performance can be monitored continuously from atmosphere down without pressure blind spots.
• Purchase of additional controller and gauge tube models is not necessary if your needs change to different segments of the range.
• A much wider range can be covered with one Convectron gauge than with thermocouple gauges.
• There is no chance of error that might be caused by using the wrong gauge tube-controller combination. One gauge tube fits all controller models.

NOTE: Due to their wide pressure range, convectron gauges can replace both thermocouple and Pirani gauges.

Features

• High performance compact vacuum controller for bench top and panel mount applications
• Wide range vacuum pressure measurement from atmosphere to 1 x 10^-4 Torr (1 x 10^-4 mbar, 1 x 10²Pa
• Direct replacement for the Series 375 Convectron Gauge Controller
• Highly visible Vacuum Florescent Display (VFD)
• Highly configurable I/O options including analog outputs, setpoint relays, serial communication interface
• Pre-programmed gas curves for N₂, Ar, He, CO₂, and O₂
• Intuitive menu control for simplified configuration and parameter setup
• Self diagnostics
• RoHJS/CE Compliant

Accuracy

The accuracy of Convectron gauges is exceptionally good. Close attention has been given in the design to minimize those factors which produce errors in conventional heat loss transducers.

High Repeatability

Repeatability of Convectron gauges is excellent. For example, in typical tests at constant temperature, Convectron gauges were repeatable to 1/10 millitorr at 1 millitorr (1 x 10^-4 mbar at 1 x 10^-3 mbar) as measured by a precision digital capacitance manometer.

Fast Response time

The sensor in a Convectron gauge tube operates in an electronic feedback loop which keeps its temperature nearly constant. Thus response time is very fast because components do not have to change temperature significantly as pressure changes.

Fig.1 - Comparison of the range of a single convectron gauge with the range of typical thermocouple and Pirani gauges.

Features

Wide Measurement Range

Direct replacement for Series 375 Convectron Controllers and allows vacuum system performance to be monitored continuously from atmosphere to 1 x 10^-4 Torr (1 x 10^-4 mbar, 1 x 10^-2 Pa)

High Measurement Resolution

Designed to take full advantage of Convectron Gauge technology with 1 Torr (1 mbar, 0.1 Pa) resolution at atmosphere and 0.1 mTorr (1 x 10^-4 mbar, 1 x 10^-2 Pa) resolution at low pressure.

Vacuum Fluorescent Display

The VFD is easier to read from greater distances than other types of displays. The display is configurable to use scientific notation or two ranges (Torr and mTorr, mbar and 10^-3 mbar, or kPa and Pa) to provide a continuous measurement readout from atmosphere to low pressure.

Process Setpoint Option

Relay contacts allow control of other vacuum equipment, such as valves, pumps, heaters, alarms, and safety interlocking

Multiple Gas Curves

Selsctable N₂, Ar, He, CO₂ and O₂ gas curves are pre-programmed, eliminating the need for individual calibration when changing the process gas.

Push-Button Controlls

Calibration and setpoint settings are easy to adjuxt using intuitive front panel controls. No special tools are required

Easy-to-use Analog Signals

Provides a one volt per decade logarithmic signal (0 - 7V or 1 - 8V) or a selectable non-linear signal (0 - 9V) that is backwards compatible with older Convectron Gauge controllers

Serial Communication Interface Option

RS-232 interface allows easy integration with computer controlled systems.

Built-in Convectron Gauge Simulator

Simulates a Convectron Gauge, which allows system diagnostics without the need of a vacuum system

Self Diagnostics

the A/D (Convectron Gauge bridge voltage) and analog outputs are continuously monitored for erroneous readings.

Compact 1/8 DIN Controller

Easy to install in space restricted locations.

Rugged All-Metal Package

Provides a high level of immunity to RF noise and is RoHS / CE Compliant

Specs

* Measurements will change with different gases and mixtures. Correction parameters for common gases are provided in the instruction manual.
‡ Convectron Gauges are not intended for use with flammable or explosive gases.

* Controller Only: Purchase cables and tubes separately.