Crown Audio CH Series Advanced Features and Options, CH and CL Series Power Amplifiers, page

CH and CL Series Power Amplifiers

4 Advanced Features

and Options

4.3.3 Fault Monitoring

The Fault (RJ-11) jack, which looks like a tele- phone plug, is located on the back of your CH or CL amplifier (Figure 4.2). It gives you an easy way to remotely monitor the amplifier’s fault status. To set up a circuit that will cause an LED to light whenever a fault status occurs, you can simply use the suggested circuit shown in Figure 4.3.

When using this circuit, the LED will glow whenever the amplifier is in one of four states: a channel’s heatsink has reached its temperature limit, the transformer has reached its tempera- ture limit, the amplifier has just been turned on and is in its turn-on-delay mode, or the ampli- fier is turned off.

If you choose to design your own circuit to interface this signal to your system, note that this RJ jack is polarity sensitive. Pin 2 must be grounded, and Pin 5 must be supplied with a positive voltage pull up (positive with respect to ground). Refer to Figure 4.4 for RJ jack pin assignments. The maximum signal that can be exposed to the fault jack is 35VDC and 10 mA. Best results are obtained with 10 mA LEDs.

The mating connector for the RJ-11 jack con- tains 4 contact pins in a 6-slot case, as shown. For additional information please contact your local dealer or Crown Technical Support.

Figure 4.2 Location of Fault Jack

Figure 4.3 Fault Status LED Circuitry

Figure 4.4 RJ-11 Jack Wiring and Pin Assignments

Operation Manual page 21