Schneider Electric FX 3NET Wartungshandbuch PDF herunterladen (Seite 22)

Installation Instruction 66571764GB3 Fire Detection 22

Schneider Electric Pelco Finland Oy Kalkkipellontie 6, 02650 Espoo, Finland Telephone: +358 10 446 511 Fax: +358 10 446 5103 www.pelco.com/nordic

Document Number 66571764GB3 16 2012

11. Addressable detector loops

11.1 Measuring the Cables

Disconnect all power from the control panel.

First disconnect the battery, then the mains

1. Measure the resistance between the loop wires + and - so

that the resistance meter positive (feeding) probe is in the

+ -conductor. The resistance must exceed 1 kΩ. If the

resistance is smaller, locate the cause of the fault and

repair it. (It may be a detector or address unit connected

the wrong way or a short circuit isolator).

>1kΩ

2. Measure the loop cable + wire resistance from the output

and return ends. Also measure the – wire. The loop

resistance of the + and – wires added together can be

max.

60 Ω on SLC - loop and 60 Ω on ALC - loop.

The difference between the + and – wire resistances

should not exceed 5 Ω. The possible causes of a fault

must be located and repaired.

Note!

If there are short circuit isolators in the loop, resistance

measuring of the loop cable will give false results. The

short circuit isolators must be by-passed by connecting

links over the isolators.

<30Ω

3. Remove short circuit isolators’ by-passes.

1 2 ... 17 18 19 20 21 22 23 24 25 26 27 ... 57 58

Keine Kommentare

Schneider Electric FX 3NET Wartungshandbuch Seite 22