7885 Digital Pressure Module

	Fully computed pressure via RS232 bi-directional data interface
	Optional RS485 data output
	Customer configurable output
	Calibration traceable to NPL and NIST

The 7885 ‘smart’ Digital Pressure Module (DPM) fulfils the need for high accuracy pressure transducers with a user friendly interface. At its core is the proven 7881 vibrating cylinder pressure sensor. The DPM module uses a Motorola micro-controller to provide a fully computed pressure output, delivered via an RS232 bi-directional data interface. RS485 data output is available as an option, enabling up to 31 units to be daisy-chained together. The 7885 DPM also features customer configurable output units and re-calibration options, within a compact enclosure.

Applications
Applications of the 7885 DPM include high accuracy ‘stand alone’ pressure standards and digital barometers for Meteorological applications. The 7885 may also be utilized as an OEM transducer for incorporation within pressure controllers, indicators and Air Data Test Sets.

Details

Characteristics
Temperature range	-40 to +70°C max
Accuracy	<0.01% FSP
Long term stability	<0.01% FSP drift per annum over full working pressure and temperature range
Start-up time	<800ms
Update time	200ms nominal
Power supply	Single rail 11-18V DC
Output format	RS232 or RS485 Serial interface, baud rate selectable, ASCII character strings
Enclosure size	<95x95x60mm plus fixing plate
Electrical Connectors	Power: 3 pin ‘Q-G’ circular type
Data:	9 pin Cannon ‘D’
User addressable software commands
Identity Send type, serial no., pressure range + factory calibration reference no.   Measurement Send continuous pressure measurement Send single pressure measurement Send single internal temperature measurement Stop measurements   Configuration Set baud rate Set pressure units, e.g. inHg, psia, kPa etc.     Calibration Re-calibration – single pressure point Re-calibration – dual pressure point Restore factory set calibration.

Model Range