Process Data acquisition system BDAT
bDat is a process data acquisition and analysis system for industrial applications. It can be integrated in an existing LAN or run on a single PC. BDAT integrates up to four PLCs ABB CS31 Procontic (Master PLC), each with several on-site modules (PLC OSM) and slave PLCs. The PLCs have the following licences: Lloyds register of Shipping, Germanischer Lloyd, CE, UL, CSA. In addition, we have developed a small controller which has a high flexibility due to its individual programmability. The detected data of the up to 6500 measurement channels is transmitted to a dedicated PC and stored in a database for analysis.
The data is collected by the PLCs. A maximum of four master PLC with six analog remote modules, 32 binary remote modules or seven slave PLC can be connected. Also various combinations of analog and binary remote modules with slave PLCs are possible. Each PLC (master or slave) captures up to 64 measurement channels. The data is cached until called by the CommServe. Data acquisition with the small controller is similar to the PLCs. Each PLC can store values of various physical quantities (like energy, pressure, power, etc.).
The CommServer collects all measurement data from the PLCs and controls and stores them in special databases. The CommServer and PLC are connected via four-wire lines (RS422A), two-wire lines (modem in leased line mode) or public telephone network (modem).
To display the actual state, data is provided online. This contains the values of the last 24 hours at selected measuring points.
To evaluate the data as many workstations (PCs) as desired can access the databases via the company internal LAN. The visualization and further processing is done by an evaluation program. Further processing using Microsoft Excel or Microsoft Access is possible. To import the data from the databases suitable routines are available.
A standard PC running Windows 95 or Windows NT is used for the CommServers. In a network application of bDAT the CommServer and the workstations must be able to access a shared network drive.
Number of measurement channels: max. 250
Number of measuring channels per PLC: 64
Number of online measuring stations: > 64 (with 1 value/s)
Measurable input signals:
- Pulse lengths (0.05 .. 320 s)
- Frequency (0.01 Hz .. 50 kHz)
- Binary signals
- Analog values
Measurement error of the data acquisition:
depending on measurement period and signal character
- Pulse: < 2% at T = 0.5 s, < 0.1% T = 10 s
- Frequency: < 1%
- Analog: < 0.2% of full scale
- Measurement period: 1 s .. 8 h
- Distance PLC - remote module: < 1000 m
Distance CommServers - PLC:
- < 1000 m (RS422A)
- < 10 km (modem, two-wire cable)
- any (modem, telephone network)