Detnov CAD-250, Руководство по установке

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37
ENG
3.13. FINAL CONNECTION CHECKS
Before connecting the control panel to the mains network, make sure
you check the following points:
1 LOOP CONTINUITY: Check the loop continuity with a voltmeter
in case there are short circuits or points where the loop is open, as
explained in section 3.7.3.
2 CHECK THE LOOP RESISTANCE: You can check the loop
resistance by joining the R+ to R- ends and measuring via the S+ to
S- ends.
The capacitance of the cable must be less than 0.5 μF.
In normal conditions, this permits a loop length of 2000 metres with
a shielded cable with a cross section of 2.5 mm
2
and a length of
1500 metres with a shielded cable of 1.5 mm
2
.
3 END-OF-LINE RESISTOR ON THE LOOPS:
Check that the main
cables of each loop have the end-of-line resistor (4k7) installed.
4 END-OF-LINE RESISTOR ON THE SOUNDER CABLES:
Check
that the main cables of the sounders connected to the MAIN BOARD
have the end-of-line resistor (4k7) installed.
5 MAIN BOARD CONNECTORS:
Check the MAIN BOARD
connectors, ensuring that the cables connected to each terminal are
not loose and the connectors are correctly and fully inserted.
6 AUXILIARY OUTPUT: Using a voltmeter, check that the voltage of
the power supply is around 230 VAC and the battery voltage around
24 V.
3.13.1. Use of ferrites
It is not normally necessary to use ferrites with the CAD-250 control
panel.
In certain situations, it is inevitable that the loop cables pass near
to power cables of industrial equipment or facilities where the
recommended cables are not used. In these cases, it is advisable to
install ferrites on the loop wiring.
The ferrites are installed on each cable, using one ferrite for the
loop's output cable (S+ and S-) and another ferrite for the return (R+
and R-). They must be installed as near to the loop card as possible,
just after the card terminal connector. The ferrite must be fixed with
a cable tie.