SMS SenTRI2, Руководство по установке, Страница: 8 / 44

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Cable for wiring Mains Supply
Cables for a SENTRI4 system
The British Standard BS 5839 Part 1 : 2017 Code of practice for system design,
installation, commissioning and maintenance states the requirements for standard and
fire resisting cables in Clause 26.2 sections d & e.
Cable for wiring Mains Supply
The mains supply cable to Control and Indicating Equipment must be a standard fire
resisting type and should meet PH30 classification.
Cable for wiring system equipment
An approved cable must be used to wire system equipment to:
†
Loop circuit
†
Master alarm circuit
†
Auxiliary relay circuit
†
Input/output circuit and
†
Mains supply.
An approved cable for wiring to these circuits is the:
†
Mineral insulated cable (MICC) to BS6207:Part 1
For alternative cables refer to the complete list of alternative approved standard and
enhanced cables for wiring system equipment, see “Loop cables” on page 9.
Cable length
The recommended cable length for respective circuit see transmission path data for
specific circuit.
Cable for wiring to RS232/RS485 ports
An approved cable must be used to wire to RS232 and RS485 ports.
The recommended cable for wiring to an RS232 port or an RS485 port is the:
†
Belden No 9729 (UL Style 2493)
y
2 twisted pairs
y
Each pair individually screened 24AWG (7 strands x 32 AWG)
y
Capacitance between conductors 39.4pF/m at 1kHz
y
Capacitance conductor to screen 72.2pF/m at 1kHz
y
Temperature range -30
o
C to +60
o
C
For alternative cables refer to the complete list of approved standard and enhanced
network cables for wiring to the RS232 / RS485 ports see ‘Network cables’ page 10.
Cable length
The recommended length of cable for respective circuit:
†
Upto 15m cable length for the wiring to RS232 port
†
Upto 1.2Km cable length for the wiring to RS485 port
Cables no longer available
7
A cross bullet point mark show a cable that may no longer be commercially
available. Such a cable if already installed in a building may be suitable for reuse
where a site is being refurbished, consult with your electrical installer.