Instruction manual

P84577 G
Sheet 4 of 14
3.2 Other Wiring
3.2.1 Expansion Circuit Wiring
The Expansion Circuits (EX1, EX2) are used to link additional audio booster panels (SPB-160, SPB-80/4, and SPB-320)
through the SP4-APS. The audio zone outputs are either 25Vrms or 70.7Vrms matching the audio input voltage. EX1
and EX2 are current limited outputs. If an over current condition is detected, the affected Expansion Zone(s) will
disable their audio output. When the over current condition has been cleared and the affected Expansion Zone(s) go
back to “Normal” condition, the audio output will be re-enabled. To ensure that current limiting works properly, for
25Vrms JP1 must be open, for 70Vrms JP1 must be closed. SPB-160 and SPB-80/4 enclosures contain one audio
booster module, while the SPB-320 contains two. The SP40/2 has a maximum audio output to the splitter of 40 watts,
while the Audio Boosters have a maximum audio output to the splitter of 80 watts. Each audio booster module
connected to the expansion circuits uses 1.2 watts. There is a limit of 33 Audio Boosters that can be connected to an
SP40/2 using SPB-160 or SPB-80/4 models. Each SPB-320 counts as two SPB-160 models.
The wiring of EX1 and EX2 for “CLASS A” or “CLASS B” is determined by the wiring of the zone outputs and switch
SW2 setting. If SW2 is set for “CLASS A”, then all zone outputs and expansion outputs must be wired for “CLASS A”.
When using the SP4-APS in “CLASS B” configuration, end-of-line resistors (UL Listed 10K Ohm, EOLR) must be
used at the end of each expansion circuit.
3.2.2 24VDC Wiring
The SP4-APS requires 24VDC input in order to operate. Wire the 24VDC from +/- 24VDC connections on the SP40/2
or the DC OUT connections on the applicable audio booster to the +/- 24VDC IN connections on the splitter. If two
SP4-APS are used on an SPB-160 or two are used with each SPB-160 in the SPB-320 audio booster enclosure, wire the
24VDC OUT connections on the first SP4-APS to the +/- 24VDC IN connection on the second splitter. Observe correct
polarity. See Figure 5 for connection locations.
OUT
IN
24 VDC
AUDIO
POWER TROUBLE
IN
JP1
TB1
TB2
JP1
Shorted = 70Vrms
Open = 25Vrms
Figure 5: 24VDC Connections
3.2.3 AUDIO IN wiring
The SP4-APS AUDIO IN uses the Audio Out from the SP40/2 or an audio booster, which is either 25Vrms or
70.7Vrms. The total audio output from all zones on the SP4-APS must not exceed its audio input power. See Table 2.
See Figure 2 for the location of the AUDIO IN. The SP4-APS uses 8 watts of audio power to operate (1.35 watts per
zone.)
Table 2: Maximum Audio Input Power to the Splitter from SP4 Products
SafePath4 Product Max number
of SP4-APS
Requires SPMB4Z
(Purchased Separately)
Max Audio Power for
Each SP4-APS
SP40/2 1 No 40W
SPB-80/4 1 Yes (1) 80W
SPB-160 2 Yes (1) 80W
SPB-320 4 Yes (2) 80W