DIGIVAC 2L760 Instruction Manual Page 3
1.0 DESCRIPTION AND PRINCIPLE OF OPERATION.
The Model DIGIVAC 2L760 senses vacuum (absolute pressure) using a precision integrated strain gauge
transducer. The transducer has a thin silicon diaphragm with an array of resistors. One side is evacuated, while
the other is exposed to the pressure to be measured. Changes in the sensed pressure cause the relative values of
the resistors to change. This result is an output voltage which is linearized, temperature compensated, scaled
and amplified. The voltage is displayed on the DIGIVAC 760 as 0 to 760 Torr or 0 to 1013 mbar.
The instrument features large, bright LEDs visible from a distance with a hard, vinyl clad metal enclosure. The
straight forward design yields a low power instrument, that is simple to build and simple to operate. The model
2L760 can be ordered with optional control relays, analog output, and RS232 output, to simplify integration with
existing process controllers or computers. In addition, this device can be Ethernet enabled, to allow monitoring
via a web browser with our free ReAct browser software. The user can access your instrument from across the
hall, or across the world. All instruments leave our factory tested and calibrated under real vacuum against a
NIST standard.
2.0 CONSTRUCTION.
The controller consists of the indicating and controlling instrument, the configured sensor, the sensor cable, the
output interfaces and an univeral AC power adapter.
The instrument is housed in a rugged free-standing vinyl clad metal enclosure. It can be placed on a level surface
for easy viewing from across the room. The gauge tube houses the sensor circuitry and terminates in an octal
connector. On this model, the connector wiring terminates at the instrument with a 9 pin DSub connection.
Regulating circuitry in the 2L760 provides constant current for gauge tube excitation, and thus compensates for
resistance in the probe leads.
3.0 UNPACKING AND INSPECTION.
After the instrument is received, it should be carefully unpacked and inspected for damage during shipment and
for completeness. In the event of a loss during shipment, a claim should immediately be made to the common
carrier or the postal service, as applicable. The DIGIVAC warranty pertains only to the instrument, and does not
cover losses in shipping. Each 2L760 should come with:
o
User Manual (this document)
o
Display controller (beige box with red lens)
o
Power supply (universal adapter with US plug)
o
Configured Sensors
o
RS232 (optional)
o
RS232 Port
o
5
’
RS232 Cable (phono to Female DB9)
o
Ethernet (optional, includes RS232)
o
Ethernet Port
o
Null modem RS232 converter
o
2’ Ethernet Cable
o
Null Modem Ethernet Cable
o
Configuration CD
4.0
INSTALLATION.
