
2-11
SIMATIC 545/555/575 System Manual
Pre-installation Guidelines
2.4 Guidelines for Fuses/Circuit Breakers
Use the following guidelines for installing fuses/circuit breakers; see
Figure 2-7. The sizes and types of fuses/circuit breakers depend on the
specified power distribution requirement.
• A circuit breaker before the isolation transformer. Isolation
transformers may not be required if your power distribution system
does not have a high level of noise.
• A fuse after the isolation transformer.
• An external fuse before each power supply.
Input Power Line
110/220 VAC
P/S
(Line)
(Neutral)
(Ground)
Controller
Remote I/O Base
Isolation
Transformer
P/S
(Line)
(Neutral)
(Ground)
Optional
Grounds
Figure 2-7 Fuse/Circuit Breaker Placement
NOTE: In order to ensure a proper level of safety compliance, observe local
codes, practices, and guidelines.
Fusing the
Controller and
Remote I/O Base
Comentarios a estos manuales