BSS Audio sw3088 Install Guide - Manual (Page 6)

Soundweb 3088 Installation Guide
6
performance pots with track resistance between 10 and 100kOhms are recommended.
Logic Outputs
Used to connect ’tally’ indicator LED’s or relays.
There are eight standard LOGIC OUTPUTS which produce 0V or +5V DC via an internal
440 Ohm resistor and two internally connected common (ground) connections “C”.
An LED connected between one output (Anode, A) and common (Cathode, K) will
illuminate when the logic output is activated, without requiring any external current
limiting resistor.
A high sensitivity relay (such as a reed relay) may be driven by connecting four outputs in
parallel. This arrangement will develop 4V across a 500Ohm coil, providing that all four
outputs are made logic 1 simultaneously.
OPTO Output
In addition to the eight standard logic outputs, there is an isolated output, which fails safe
(open circuit) if the unit becomes faulty.
This is effectively the collector-emitter of a transistor (which may be thought of as a
switch), in series with a 220-Ohm protection resistor. In conjunction with an external DC
power source (max 80V), this may be used to drive various loads such as relays.