NFW-50X Manual —
P/N LS10129-001NF-E:C 7/25/2018
139
NAC Wiring
Wire Requirements
D.1 NAC Wiring
The following table lists NAC wiring requirements for the FACP.
Notes:
1.
Calculations are based on Direct-Current Resistance data for
uncoated copper wire
, per National Electrical Code (2011 Edition)
Table 8, Conductor Properties.
2.
These distances reflect the worst case scenario and are based on the current draw of the highest candela strobes at the low end of the
supported NAC voltage with the entire load at the end of the circuit. Further distances can be achieved by performing a point-to-
point voltage calculation that more accurately reflects the specific devices used and how they are dispersed on the circuit.
3.
If using Gentex brand notification appliances, the “UL Max” current rating published in their data sheets, must be used in order to
maintain performance under low battery conditions with the maximum wire resistances shown in the table above.
NAC Load
(Amps)
Max.
allowable
total loop
resistance
(ohms)
CLASS-B
Max. allowable wire pair length
(feet)
CLASS-A
Max. allowable wire pair length
(feet)
AWG 12
solid
AWG 14
solid
AWG 16
solid
AWG 18
solid
AWG 12
solid
AWG 14
solid
AWG 16
solid
AWG 18
solid
0.25
14.40
4450
2797
1756
1105
2225
1399
878
553
0.5
7.20
2225
1399
878
553
1112
699
439
276
0.75
4.80
1483
932
585
368
742
466
293
184
1
3.60
1112
699
439
276
556
350
220
138
1.25
2.88
890
559
351
221
445
280
176
111
1.5
2.40
742
466
293
184
371
233
146
92
1.75
2.06
636
400
251
158
318
200
125
79
2
1.80
556
350
220
138
278
175
110
69
2.25
1.60
494
311
195
123
247
155
98
61
2.5
1.44
445
280
176
111
222
140
88
55
Table D.2 NAC Wiring Requirements for FACP