Secutron MR-2900 Installation Manual page 21

Note: T-taps may NOT be allowed by the authority having jurisdiction. Refer to NFPA 72 and
ULC-S524. This circuit may be wired on any input circuit from 9 to 24 on the MR-2900 terminal
boards.
Addressable Style 6 (Class A) Circuit
Figure 14: Addressable Style 6 (Class A)
Wiring
Notes:
• All distances refer to total wire length.
• This circuit may be wired on any input circuit from 9 to 24 on the MR-2900 terminal boards.
Table 3: Maximum Wiring Length for Addressable Circuits
Gauge Belden No.
12 9582
14 9580
16 9572
18 9571
This is a 4-wire power-limited and supervised Style 6 (Class
A) communications circuit using addressable devices. It
requires the use of the MR-2929 or MR-2919 module.
Maximum wire loop lengths are up to 10 000 ft (see Table
3). The recommended wiring is twisted unshielded pair.
Wire capacitance and resistance affects the allowable wire
length. Consult Secutron's Applications Department for
specific requirements. Devices are connected as illustrated
in Figure 14. Use only approved devices. Return wiring
must be in a separate conduit. When using isolators, it is
necessary to put an isolator between panel terminal blocks
and the device.
Distance
3 048m (10 000 ft)
2 438m (8 000 ft)
1 402m (4 600 ft)
975m (3 200 ft)
MR-2900 Installation Manual
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