Ziton ZP2 Series, Руководство по установке

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Chapter 2: Installation
ZP2 Series Installation Manual 27
• Ensure that the loop cable complies with the cable specifications outlined in
“Recommended cables” on page 24.
• If using shielded loop cable, ensure that the shield is continuous (connected
through to each loop device). To prevent earth loops caused by
electromagnetic interference, only one cable shield should be connected to
earth, as shown in Figure 12 on page 25.
Class A loop connection
Connect Class A loops as shown in Figure 12 on page 25. Class A loops are
supervised for open and short circuits. Terminate unused Class A loops A (+) to
B (+) and A (−) to B (−).
Class B loop connection
Caution:
Class B loops do not comply with EN 54-13 requirements. Never install
more than 32 devices on a Class B loop.
Connect Class B loops as shown in Figure 14 below. Connection may be made
to either the A connectors (as shown) or to the B connectors, but not to both.
Class B loops are supervised for short circuit.
Figure 14: Class B loop connection