4.3.2 Wiring distances
Table 9 and Table 10 list the maximum distances from the NAC terminal block to the last appliance in a Class A and Class B configuration,
depending on wire gauge and current. Use Table 9 and Table 10 to calculate the wire distances for your application.
Table 9: Class A wiring distances
Alarm current Max distance w/ 18
AWG (0.8231 mm
2
)
Max distance w/ 16 AWG
(1.309 mm
2
)
Max distance w/ 14
AWG (2.081 mm
2
)
Max distance w/ 12
AWG (3.309 mm
2
)
DC resistance
0.25 A 420 ft (128 m) 667 ft (203 m) 1,063 ft (324 m) 1,691 ft (515 m) 6 Ohms
0.50 A 210 ft (64 m) 334 ft (102 m) 532 ft (162 m) 845 ft (258 m) 3 Ohms
0.75 A 140 ft (43 m) 222 ft (68 m) 354 ft (108 m) 564 ft (172 m) 2 Ohms
1.00 A 105 ft (32m) 167 ft (51 m) 266 ft (81 m) 423 ft (129 m) 1.5 Ohms
1.25 A 84 ft (26 m) 133 ft (41 m) 213 ft (65 m) 338 ft (103 m) 1.2 Ohms
1.50 A 70 ft (21 m) 111 ft (34 m) 177 ft (54 m) 282 ft (86 m) 1 Ohm
1.75 A 60 ft (18 m) 95 ft (29 m) 152 ft (46 m) 242 ft (74 m) 0.86 Ohm
2.00 A 53 ft (16 m) 83 ft (25 m) 133 ft (41 m) 211 ft (64 m) 0.75 Ohm
2.25 A 47 ft (14 m) 74 ft (23 m) 118 ft (36 m) 188 ft (57 m) 0.67 Ohm
2.50 A 42 ft (13 m) 67 ft (20 m) 106 ft (32 m) 169 ft (51 m) 0.60 Ohm
2.75 A 38 ft (12 m) 61 ft (19 m) 97 ft (30 m) 154 ft (47 m) 0.55 Ohm
3.00 A 35 ft (11 m) 56 ft (17 m) 89 ft (27 m) 141 ft (43 m) 0.50 Ohm
Table 10: Class B wiring distances
Alarm current Max distance w/ 18
AWG (0.8231 mm
2
)
Max distance w/ 16
AWG (1.309 mm
2
)
Max distance w/ 14
AWG (2.081 mm
2
)
Max distance w/ 12
AWG (3.309 mm
2
)
DC resistance
0.25 A 840 ft (256 m) 1,335 ft (407 m) 2,126 ft (648 m) 3,382 ft (1,031 m) 12 Ohms
0.50 A 420 ft (128 m) 667 ft (203 m) 1,063 ft (324 m) 1,691 ft (515 m) 6 Ohms
0.75 A 280 ft (85 m) 445 ft (136 m) 709 ft (216 m) 1,127 ft (344 m) 4 Ohms
1.00 A 210 ft (64 m) 334 ft (102 m) 532 ft (162 m) 845 ft (258 m) 3 Ohms
1.25 A 168 ft (51 m) 267 ft (81 m) 425 ft (130 m) 676 ft (206 m) 2.4 Ohms
1.50 A 140 ft (43 m) 222 ft (68 m) 354 ft (108 m) 564 ft (172 m) 2 Ohms
1.75 A 120 ft (37 m) 191 ft (58 m) 304 ft (93 m) 483 ft (147 m) 1.71 Ohms
2.00 A 105 ft (32 m) 167 ft (51 m) 266 ft (81 m) 423 ft (129 m) 1.5 Ohms
2.25 A 93 ft (28 m) 148 ft (45 m) 236 ft (72 m) 376 ft (115 m) 1.33 Ohms
2.50 A 84 ft (26 m) 133 ft (41 m) 213 ft (65 m) 338 ft (103 m) 1.2 Ohms
2.75 A 76 ft (23 m) 121 ft (37 m) 193 ft (59 m) 307 ft (94 m) 1.09 Ohms
3.00 A 70 ft (21 m) 111 ft (34 m) 177 ft (54 m) 282 ft (86 m) 1 Ohm
Note:
• Max distance = distance from the power supply to last appliance.
• This table is calculated at 49°C (120°F). If you are installing in locations with higher temperatures than 49°C (120°F), refer to NEC Table
8.
• Distances are based on a 3 V drop, and take into account the worst-case panel output voltage.
• If you use circuit integrity wire instead of housing cable in a fire-rated enclosure, reduce the wiring distances by 38 ft (12 m) for every
10 ft (3 m) of potential exposure.
page 18 579-1102AR Rev C
Z-20 Agent Releasing Panel Installation Manual