Hardware Manual

Hardware Manual PCD 1 / PCD 2 Series│Document 26 / 737│Edition EN 15│2008-07-22

Saia-Burgess Controls AG

PCD2.W6x5

Input/output (I/O) modules

5

Terminals

Digital/analogue values

Output signals and type Digital values

PCD2.W605 PCD2.W615 PCD2.W625 Classic xx7 Simatic

+ 10.0 V + 20 mA +10 V 4095 4095 27684

+ 5.0 V + 10 mA 0 V 2047 2047 13842

0 V 0 mA -10 V 0 0 0

Notes on the output range

Balancing the offset and the amplification is done for the PCD2.W6x5 digitally by the

μC. As there is no potentiometer, the output range has been slightly enlarged to cover

maximum values even in the worst case.

Typical output range (without component tolerances):

W605: - 0.26 V ... + 10.36 V (instead of 0 ... + 10 V)

W615: 0 mA ... 21.4 mA (instead of 0 ... 20 mA)

W625: - 10.62 V ... 10.36 V (instead of - 10 ... +10 V)

This range is broken down on a 10 bit scale (1024 steps), as before. The result is the

following LSB resolution:

W605: 1 LSB = 10.38 μV

W615: 1 LSB = 21.7 μA

W625: 1 LSB = 20.75 μV

With this balance the nominal range (0 ... 10 V) is now scaled 0 ... 1023, making it pos-

sible for the output value not to change on an increase of 1 LSB.

In the FBs the output values are not limited to 0 ... 1023, so the whole range of the

module can be used.

For voltages > 10 V or currents > 20 mA, values >1023 may be output, and for

voltages < 0 V or