Technical data

Chapter 4: Installation
Series SPB Audio Boosters Manual, Revision A
4-9
4.2.5 Installing Strobe Input Connections (SPB-80/4)
The strobe input circuit (STB IN) consists of either a power limited 8-33VDC regulated NAC
circuit input or a contact closure input. The input uses reverse polarity for supervision. The strobe
return (STB RET) can be used to link other Series SPB Audio booster strobe NAC circuits to the
host voice evacuation panel, additional strobes powered by the host panel, or connecting the host
panels 1/2W EOLR. The strobe output provides a synchronized output for compatible Wheelock,
Inc. synchronized strobes.
Strobe Input and
Strobe Return
Figure 4-6 Strobe Input Connections (SPB-80/4)
Connect the strobe input to the STB IN terminals. Connect the proper device or connection to the
STB RET.
4.2.6 Installing Audio and Strobe Output Circuit Connections
NOTE: Install a UL Listed 10K Ohm 1/2W EOLR on both AUD1 and AUD2 (SPB-160 and
SPB-320 only) outputs for supervision whether they are used or not. If the audio circuit is used,
place the UL Listed 10K Ohm 1/2W EOLR on the last audio appliance on the circuit. Failure to
do so causes an open condition, causing the TROUBLE LED D73 to turn on as well as the
respective OPEN LED to light.
NOTE: AUD1 and AUD2 are two separate 80-watt, Class B, power-limited audio output
circuits. Do not wire AUD1 and AUD2 together.
NOTE: The maximum line impedance for the strobe circuit is 40 ohms.