Turning ALC Amplifiers On or Off from Tesira
First Step
To begin, we need to understand that the amplifier has an internal bi-stable switch that controls whether it is ON or OFF. As shipped it is ON, as soon as it’s plugged in, it powers up. This internal switch can be changed by pushing and holding the front panel power button, under the left cover for about 3 seconds. Note: this action only takes place after it is fully booted from being plugged in. It will hold this state through a hard power cycle, including unplugging it from the wall. In order to use REMOTE ON, one must first place the amplifier in OFF mode by pushing the power button for 3 seconds after it’s fully booted.
The Tesira is fully flexible and can invert the logic, so using REMOTE OFF works just as well. We recommend using Remote ON if using it to power the system and Remote OFF if the system needs to be muted by a fire alarm panel, because it's more logical, but it can work either way. Keep in mind that a battle between Remote ON and Remote OFF will be won by ON, so if using using both, the fire panel will need to interrupt the ON signal.
Second Step
Set up the Tesira Logic out as a powered output, as though driving an LED. Since the ALC's Remote ON terminals draw less current than an LED, you can run up to three on each logic output. The ALC's remote terminals are not polarity sensitive, either polarity works.
If you need to power on a large number of amplifiers, use an external power supply power with the logic output configured as an open collector and you can power many dozens of amplifiers. Since the ALC has inrush current control, there is no need to sequence them ON.