NAC Circuit Wiring
2.3.2 Two NACs Configured for Class A (Style Z)
Figure 2.11 shows two NACs configured for Class A (Style Z).
• Trouble on NAC1
LED1 SIG1 TRBL and
LED2 SIG2 TRBL
• Trouble on NAC2
LED3 SIG3 TRBL
and LED4 SIG4 TRBL
1. Typical ELR's for new installations can be 3.9k or 4.7k ohm.
2. The same gauge wire must be used if two conductors are connected to the same terminal of
any terminal block.
3. Do not complete a continuous circuit around the screw terminal. There must be two separate
wires on either side of the screw at the terminal block. "T-tapping" is absolutely NOT ALLOWED.
HPFF12 NAC Expander — P/N 53576:B 11/24/2010
Note: NAC 1 Class A
wired same as NAC2.
Figure 2.11 Two NACs in Class A (Style Z)
Note: NAC 2 in Class A;
no ELR required.