Aritech 2000 Series, Руководство по установке

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2000 SERIES SENSORS INSTALLATION GUIDE Revision 3.1 June 1997
Note: Where (non-addressable) intrinsically safe detectors are to be used, the Zener
barrier must be placed in the safe area adjacent to the hazardous area.
2.5.2 Indicating Circuit Controller IU2080
GENERAL DESCRIPTION
The IU2080 provides an interface between the two wire multiplexed ring circuit and local
supply loop sounders and strobes with their associated user supplied external power
supply. The local supply loop circuit can be selected for a 12V or 24V application. The
selection is done by the S2 switch located on the board. If the switch is closed, the loop
is set to the 12V application and if the switch is open the loop is set to the 24V
application. The external power supply provides the power to drive the sounders and
strobes. A number of devices totalling up to 3A may be connected to the sounder spur
(750 mA in applications requiring AFNOR approvals).
The ICC monitors the local power supply for a low voltage condition and the external
fault relay contacts (via fault +-ve) for an open condition. An end of line resistor is used
to ensure that the local supply loop is intact. The ICC monitors for loop shorts as well as
for loop open circuits via this resistor. Moreover, the ICC can provide a means for EOL
monitoring via a Z-style connection back to the ICC itself.
The PCB has to be put in a housing, according to environmental conditions.
INDICATORS
The IU2080 contains a red LED that will light when the relay is in a position to cause the
sounders and sirens to be energised. The green LED indicates that the external power
supply voltage is present and greater than approximately 8 volts.
ADDRESSING
The address of the ICC is set by a dip switch on the ICC circuit board. The decimal
address of the ICC must be converted to a binary number to set the dip switch. Please
refer to paragraph 2.3 (MCP) for the complete table.
TECHNICAL DATA
Operating voltage ........................... 17 - 28V (at the communication loop terminals)
Total standby current ...................... < 350 mA (< 200 µA typical)
Maximum loop alarm current........... < 3.5 mA
End of line resistor value ................ 10 K 1/4W, 5%
Bell loop impedances at 24V:
Short circuit..................................... < 3.3 K
Quiescent ....................................... 3.3 K - 13.0 K
Open circuit..................................... > 13.0 K
Local power supply, low voltage detection:
12V supply...................................... <10.2V
24V supply...................................... <20.4V