DMP Electronics 7000INT Series, Installation And Programming Manual

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Digital Monitoring Products, Inc | 7000INT Series Installation and Programming Guide 29
WIRING SPECIFICATIONS
When planning a keypad bus installation, keep in mind the following specifications:
• DMP recommends using 18 or 22 AWG unshielded wire for all keypad and LX-Bus
circuits. Do not use twisted pair or shielded wire for LX-Bus and keypad bus data
circuits. To maintain auxiliary power integrity when using 22-gauge wire, do not
exceed 500 feet. When using 18-gauge wire, do not exceed 1,000 feet. Install an
additional power supply to increase the wire length or add devices.
• Maximum distance for any one circuit (length of wire) is 2,500 feet regardless of the
wire gauge. This distance can be in the form of one long wire run or multiple branches
with all wiring totaling no more than 2,500 feet. As wire distance from the panel
increases, DC voltage on the wire decreases.
• Maximum number of devices per 2,500 feet circuit is 40.
Note:
Each panel allows a specific number of supervised keypads. Add
additional keypads in the unsupervised mode. Refer to the panel installation
guide for the specific number of supervised keypads allowed.
• Maximum voltage drop between the panel (or auxiliary power supply) and any device
is 2 VDC. If the voltage at any device is less than the required level, add an auxiliary
power supply at the end of the circuit. When voltage is too low, the devices cannot
operate properly.