The latest additions to the Yokogawa Daqstation family of paperless recorders are the S120 versions of the DX100 and DX200 units, which offer a number of enhanced functions and new capabilities
The Daqstation DX series is a family of advanced data-acquisition stations which combine the capabilities of intelligent paperless recorders with powerful communications and networking capabilities.
The units feature easy-to-read colour TFT displays: a 5.5-inch display for the DX100 and a 10.4-inch display for the larger DX200.
New features in the S120 models include additional thermocouple and RTD inputs, an increase in the number of messages that can be output from eight to 56, a number of new display functions, media Fifo (first-in/first-out) capability, internal switching, and the implementation of SNTP (simple time network protocol).
A key new feature for plant operators is automatic display recovery, where the unit automatically returns to the default display if, for example, another operator has been viewing a different set of parameters.
The recovery time can be set to between one minute and one hour.
On the S120 version of the DX100, a split trend display can be implemented, while on both units the user is able to select logarithmic or scaled bargraph display formats along with the graphical data record.
A colour-band and alarm-mark display is also available, in which the trend window includes a scaled bargraph indication of bands in a defined colour, while the bargraph window includes an additional colour band in the same colour.
Different-coloured alarm marks correspond to the four alarms for each channel.
It is also possible to speed up the trend display for monitoring purposes - in case an alarm occurs, for example - in a process similar to that of speeding up the paper drive in a chart recorder.
This action can be initiated manually, by an internal switch, or via one of the unit's communications interfaces.
The new media Fifo capability is designed to ease the operation of the recorder with external media such as Zip or ATA drives.
When the external storage capacity is full, the oldest data files are automatically deleted and replaced by the latest.
If an error occurs with the storage media, the system automatically generates an error mark, activates the 'memory full' relay, and sends an email.
Each unit incorporates up to 30 internal switches which are activated by the alarm function and initiate a number of actions including an event data trigger and on-screen messages.
The new SNTP capability allows the unit to function as an SNTP client or server, and ensures that all recorders in a networked installation are automatically synchronised.
Automatic configuration for daylight-saving time is also included.
Finally, the new recorders can handle larger mathematical expressions than earlier models.
Up to 120 characters can be used in arithmetic expressions; the stack of channels and constants used in arithmetic expressions is extended to 35; and the number of constants available for the DX100 is increased to 30.
