Fagor APS-24, Руководство по оборудованию

Страница: 272 / 386

   Installation
312
8.
INSTAL
LAT
ION
Locatio
n
272
DDS
HARDWARE
Ref.1310
Use equipotential wires in systems with:
MANDATORY.
•
Wide-area installation.
• Different voltage sources.
• Mains through several buildings reducing the current in the cable shield
and the emissions. Connect to ground the electrical cabinet, the door,
the mounting plate, with ground straps or cables with a cross section
larger than 10 mm² (6 AWG).
• The ground shields of the digital signal wires must be connected at both
ends to a large surface or through a conductive housing of the connec-
tor. This reduces disturbances that affect the signal cables and also the
emissions.
• The ground shields of the analog signal wires must be connected direct-
ly to the device (signal input), reducing the ground loops due to low fre-
quency disturbances.
• When a unit does not have a ground connection, the shield must be
connected on the side of the unit connected to ground.
• To connect large cable shield surfaces, use cable and ground clamps.
• Run a single shielded cable, in one piece, without joints. If a cable must
necessary be cut for the installation, connect it with the shield connec-
tions and through a metal cover at the cut (joint) point. In the worst
case, if it is not possible to use shielded connectors, keep a minimum
length of cable exposed to disturbances guaranteeing a good connec-
tion between the shields. See figure
F. H8/2 . A .
• Mount switching devices such as contactors, relays or electro-valves
with interference suppression elements or arc suppressors (e.g. di-
odes, varistors, RC circuits).
• Install power and control components separately.
• Install before mains and the servo drive system mains chokes to re-
duce harmonics and expand the useful life of the product. EMC limit val-
ues may be improved by also using external filters.
• Use equipotential cables when having long lines to reduce the current
through the cable shield.
• When connecting power cables, the shield of this cable should be con-
nected to a ground bar. See figure
F. H8/2 . B .
F. H8/2
A.
Make the shielded cables as short as possible when the connectors
are not shielded. B. Connection of the power cable shield to a bar that is
connected to ground.
A B