UTC Fire and Security M3000, Руководство по установке

Страница: 81 / 174

Chapter 5
Reader processing boards
71
Wiring DIs
Each reader port has two supervised digital inputs which are used for door status devices (door contacts and
exit request input). Since these digital inputs are supervised, they require end-of-line resistors.
To wire a DI:
1. Follow the installation specifications for the device. Mount the device according to the manufacturer’s
specifications. The alarm device (door contact) should have a dry contact which can have a Normally
Open or Normally Closed type switch. A Normally Closed contact is in its normal or resting position
when it is closed. For example, the contact is closed when the door is closed. The opposite is true for a
Normally Open contact. In this case, the contact is open when the door is closed.
2. Select the appropriate digital input for each alarm input device.
3. Ground the shields of the cable at the M3000 enclosure grounding studs. Insulate the shield (with tape
or shrink tubing) at the DI device end to avoid electrical noise.
4. Install two end-of-line resistors. Install each resistor as close to the door status contact as possible.
5. We recommend the standard 1,000 (1K) ohm, 1/4 watt, 5% tolerance, high-quality end-of-line
resistors. This board also supports 6.8K and 18K end-of-line resistors. See Figure 19 on page 72 for
the location of the resistors. See Table 26, Supervised DI end-of-line resistors on page 63 for the
appropriate switch settings.
6. Wire the supervised door DI between pin 8 (Door DI) and pin 9 (Door DI Return). Wire the supervised
exit DI between pin 5 (Exit DI) and pin 10 (Exit DI Return). The contact can be Normally Open or
Normally Closed.
7. Insulate resistors with tape or heat shrink tubing.
8. Document how you wired the alarm input devices. Future expansion of the system and its maintenance
depend upon accurate documentation.
CAUTION: The supervision capability will be impaired if the resistors are NOT wired immediately adjacent to the
door status contact.