Overview of application
ABB needed a data
acquisition system for a total of more than 400 hardware
channels to be delivered within 3 weeks and ready to run
within 5 weeks.
Due to a highly
distributed topology the system provided required a total
of 13 network nodes. Channel to channel isolation of
around 200 V was required for the thermocouple inputs,
this was provided by the 7027 Reed relay module.
The system is used to
monitor the operation of a gas turbine, and acquire all
necessary data to calculate the efficiency of the
turbine. This requires very high precision instruments.
The gas turbine in Kawasaki is used mainly for
demonstration purposes and usually runs less than 12
hours, at times all 400 channels need to be acquired
within 5 minutes (80 channels per second). The software,
Labtech Control for Windows, is used to calculate the
different calibration polynomials for the pressure
transmitters and the RTD's (total of approximately 70
polynomials) and to allow alarm monitoring and on-line visualisation.
Datascan was chosen for
its high precision, and long term stability due to the in
built automatic calibration facility as well as its
networking flexibility and fast and easy installation
less than 5 weeks).
