Installing and Controlling Third-Party Devices
Nelson Interfaces: Differences from Conventional Nelson Box Installations

Sequence Processing and Buffer Action

Conventional Nelson data systems, such as ACCESS*CHROM, allow recording entire sequences with the box as long as there is sufficient buffer space. The data is then transferred to Chromeleon.

Chromeleon reads the data immediately, so that virtually no buffer action is required. The buffer only temporarily stores data during delays in data transfer (usually less than one second).

In Chromeleon, it is necessary to first define the sequences; that is, the number and run time of the samples. Recording data is only possible if Chromeleon is ready. Chromeleon uses the ready relay to indicate the ready status.

Using the Stop Input

Operators working with conventional Nelson Box Installations are used to define the end of data acquisition via the stop input of the box. Chromeleon does not support this. The end time must be explicitly defined in the Program.

Why is the Box not "Ready"?

As mentioned above, Chromeleon uses the ready relay to indicate the ready status. The ready relay is switched on during the Inject command. Otherwise, it is switched off.

How can you prevent loss of data when Chromeleon does not use the buffers as no data because the program does not expect any data?

Use the Ready output of the box. Most samplers are fitted with a suitable input (Ready, Remote Start, etc.).

For more information about how to install the Nelson Interfaces, refer to:

 Nelson Interfaces: Installation

 Nelson Interfaces: Overview

 Nelson Interfaces: Connections

 Nelson Interfaces: Device Driver Configuration

 Nelson Interfaces: Properties

 Nelson Interfaces: Data Acquisition Restrictions