Hardware Installation Guide for the Polycom SoundStructure C16, C12, C8, and SR12
Logic Output
SoundStructure Powered Relay
5 V Relay
Pin 1 : +5 V
Pin 2 : Logic Output 1
Remote Control
External Device to be Controlled
Relays rated for +5 V or lower may be driven directly from the +5 V logic connector pin 1 supply. Relays rated for more than +5 V will need an external power supply as described in the next example.
When the logic output (Pin 2 in this example) is set on (high), current flows from Pin 2 to ground and current that flows will energize the relay coil and close the relay contact. When the logic output is set off (low), current will stop flowing to the relay coil, causing the relay contact to open. A diode is recommended to be placed in parallel with the relay to provide a path for the discharge current of the magnetic coil of the relay. This current will discharge over a very short period of time and a diode capable of handling a large amount of surge current such as the IN4001 is recommended and is available from several manufacturers.
This example circuit uses an Omron G5CA relay and the coil resistance is 125 ohms. Because of this coil resistance, an additional series resistor is not required to limit the current from the 5 V supply to less than 500 mA in this example.
Externally Powered Relay
| External +12 V |
Pin 25 : Ground | - + |
| |
| Pin 2 : Logic Output 1 |
Remote Control
12 V Relay
External Device to be Controlled
SoundStructure can be used with externally powered relays when the following conditions exist:
•The relay is DC powered.
•The DC voltage does not exceed 60 V.
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