Application note PD 640
Analogue input/output: 4 x (0-20mA / 4-20mA)
The PD 640 contains 4 analogue channels, of which 2 channels can be configured for analogue input or analogue output, and 2 channels are permanent analogue inputs.
When a channel is used as an analogue output, the input channel reads back the actual current of the output.
All PROCES-DATA modules are based on the Channel concept. A channel is a functional object, consisting of functions and all function related data.
A PD 640 Module consists of 3 channel types:
– Service channel:
– Analogue Input/Output channel:
– Analogue Input channel:
General module behaviour and interface.
Functions and data for analogue input / output.
Functions and data for analogue input.
An Analogue Input/Output channel in a PD 640 module is identical to an Analogue Input channel except for the addition of two output registers:
– Percentage output and Scaled output
Also, the channel configuration enables the selection of input or output:
– Signal type
Analogue Input channel description:
Input channels provided by PROCES-DATA contain much more than just the basic input function. The input channel functions and associated parameters are formed into a channel description. The module’s integrated controller handles all channel functions.
Functions need only to be configured for operation. No additional programming is required.
Analogue Input Channel monitors:
– Signal out of range
– Wire broken (4-20mA mode only)
Analogue Input Channel functions:
– Input signal scaling to SI unit
– Analogue Input Filter
Analogue Input/Output Channel functions:
– Output percentage
– Output scaled
PD 641 Application Notes (Pt100 / Pt 1000)
PD 642 Application Notes (mV / thermocouple)