Hardware Manual

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

Saia-Burgess Controls AG

Power supply and connection plan

CPUs and expansion housings

3

3.9.2 Earthing and connection plan

Ground wire plan with earthing bar

PGU

24 VDC

Battery

WD

Run

Halt

Error

CPU

Supply

0V +24VDC

1.5 mm^2 1.5 mm (^2)
Exxx Axxx
Wxxx
Earthing bar
_

_
++

• Shielding and
  grounding plate
  1.5 mm^2 / max. 25cm
  In the bottom part of the PCD1/PCD2 housing there is a shielding and earthing
  plate. This constitutes the common, large-area ground for all I/O modules and for the
  external power supply.
  When a module is plugged in at the I/O level, the blades on this plate ensure a
  reliable multi-point contact to the relevant module.
  The zero-potential (Minus pole) of the 24 V supply is connected to the Minus
  terminal of the PCD1/PCD2 supply. This should be connected to the earthing bar
  with the shortest possible wire (< 25 cm) of 1.5 mm^2. The same applies to the Minus
  connection to the F1xx or the interrupt terminal.
  Any shielding of analogue signals or communication cables should also be brought to
  the same earth potential, either via a Minus terminal or via the earthing bar.
  All Minus connections are linked internally. For problem-free operation, these
  connections should be reinforced externally with short wires of 1.5 mmly with short wires of 1.5 mm^2.