The D8500 2-channel voltage/current output module is part of the DGH’s D8000 data acquisition module family with USB interface. This analog output module generates DC voltage and current signals across voltage ranges of 0-10V, ±10V and current ranges of 0-20mA, 4-20mA, at the rate of 250 conversions per second. Utilising 12-bit digital-to-analog (DAC) converter, the user is able to select the output signal type for each channel and control both independently via a host computer using the Modbus RTU protocol. A range of additional programmable features is available, such as output slew rate, startup signal value or a communications watchdog times which can be used to move the analog output signal to a known “safe” condition in an event of communication failure. The D8500 output module contains no pots or DIP switches. For extra security, it utilises a non-volatile EEPROM (Electrically Erasable Programmable Read Only Memory) to store all user-selectable settings such as the range, meaning the values are maintained in the event of power loss. The D8500 module connects to the computer via USB interface and is compatible with any commercial software supporting Modbus RTU protocol and is DIN-rail mountable (MK-1 mounting kit required). Combined with other D8000 modules, it provides the complete, customised data acquisition system for given application.

• 2-channel analog output module
• Connects to the computer via USB interface
• Voltage ranges: 0-10V, ±10V
• Current ranges: 0-20mA, ±20mA
• Modbus RTU protocol
• User-selectable features include analog output type and range per channel, output slew rate, startup signal value, communication watchdog timer, baud rate, parity type and others
• Two 12-bit DAC converters, 250 conversions per second
• Compatible with all commercial software programs supporting Modbus RTU protocol, including programs from Wonderware, DreamReport, National Instruments Labview, Indusoft and others
• Accuracy: ±0.1% of full scale maximum
• Span temperature coefficient: ±25ppm/°C maximum
• Settling Time to 0.1% of the full scale: 1ms
• Communications watchdog timer
• Current Output Compliance: ±12Vdc
• Input burnout protection to 250 Vac
• Power requirements: Serial = 2.1W
• Temperature range -25°C to +70°C
• Mix and match with other D8000 modules to build a complete, customised data acquisition system

The applications for the D8000 data acquisition modules include:

• Process monitoring and control
• Remote data logging to any host computer
• Product testing