Karel MS224, Инструкция по установке и обслуживанию

Страница: 49 / 81

Karel MS224 Installation & Maintenance Guide
Edition 3.2
46
The BPL224 backplane comes already installed in the system cabinet, as fixed to
the top and bottom rear parts of the metal rack by 8 screws, 4 at the corners and 4
in the middle.
•
R
EMARK
The internal modules must be installed from right to left, starting from SPS224
Power Supply Module.
IMPORTANT
The equipment can be installed only by the service personnel.
The area behind the front cover is not for operator access, hence the
front cover can be opened only by the service personnel.
The mains socket should be installed near the equipment or should be
easily accessible.
II.1. GROUNDING
The chassis ground of the MS224 system also serves as the signal ground, which
takes place on all the cards as a reference for the existing signals.
The chassis ground has an utmost importance for the protection of the system
against lightning or high voltage coming through lines, extensions or mains.
The chassis ground is partly established through the mains cable of the system,
which is equipped with the ground wire. Due to this reason, it is recommended to
operate the system over a mains plug that is properly grounded.
Checking whether the mains ground is proper or not requires some special devices.
But it is possible to have a rough idea about the mains ground simply by measuring
the voltage across:
•
The phase and the neutral; it must be in-between 180 VAC and 260 VAC.
•
The ground and the neutral; it must be around 1-2 VAC.
However, even if the mains outlet is properly grounded, it may not be sufficient by
itself for MS224. So, it is also strongly recommended to make a separate and
private ground connection for MS224. The best way to construct an ideal ground for
this purpose is to insert a metal bar (of at least 1.5 m length and 1.5 cm radius,
copper is preferable) into the earth, as illustrated in Figure B-2.
To establish the connection of the system to such a ground surface, the yellow
ground screw that is located below the rightmost metal slots of the cabinet the
ground screw (the slots that carry SPS224 Power Supply Module, as illustrated in
Figure A-4) must be connected to the ground surface.