Control the dosing level of a liquid or gas
This application note describes how the nanodac can be used to control the dosing level of a liquid or gas using the Feedforward feature of the PID algorithm to achieve an output proportional to the flow rate of the fluid.
nanodac Data Recorder with PID Control
The nanodac recorder/controller provides combined recording and control in a single ¼ DIN package.
It is ideal for use on any application requiring up to four real universal inputs. An additional fourteen inputs can also be written to over communications effectively making an eighteen channel data logger. It also contains two PID control loops which can be configured to control process variables such as flow, level, pressure, temperature, etc,.
In addition to the features listed above, the nanodac recorder provides powerful logging and secure archiving of the data. It can store information in either open CSV format or in a secure (UHH), check summed format to protect data integrity.
In addition to live trending, a simple menu allows any selected portion of the recorder history to be archived, either to a ‘memory stick’ plugged into the USB port at the rear of the recorder (Local Archiving) or to a computer or server, by means of the FTP protocol (Remote Archiving). The archived data remains in the flash (50MB) memory of the instrument and can be reviewed directly on the instrument display.
The archive period can be chosen between the last hour, last day, last week, last month, archive everything in the recorders history or archive all files created since or updated since the last archive.
The status of the archive is displayed on the nanodac recorder/controller which shows when data is being transferred or is complete.
The archive data includes actual values from real or communications channels (PV), Alarm Messages, and Operator Input Messages all of which are accurately dated and time stamped from the on-board real time clock.
