per channel or 4 ohms BRIDGE mode for any application. Operation at loads of 4 ohms per channel or 8 ohms BRIDGE mode is more desirable for sustained operation applications, be- cause the amplifier will run much cooler at this load. Operation above 4 ohms per channel and even open-circuit conditions can always be considered safe; however, sustained operation at loads below 2 ohms could result in temporary amp shutdown due to operation of the thermal limiting and/or the fault detection circuitry.
INSTALLATION AND CONNECTION
The Peavey CS 1200X Commercial Series Power Amplifier is designed for durability in com- mercial installations and quality of performance required in studio and home applications, The unit is a standard 19” rack-mount configuration that requires 7” rack height; it is cooled by an automatic two-speed internal fan. The front panel contains various LED indicators for the moni- toring of power output, DDT activation, and thermal shutdown. Detented and calibrated input sensitivity controls and a heavy-duty mains power switch are also provided. All inputs, outputs, and patch points are on the back panel,
MAINS POWER SOURCE
If possible, each amplifier should be connected to separate mains circuits capable of delivering at least 15 amps continuously. This is most critical for sustained high-power applications into
2 ohms per channel. Never break off the ground pin on the CS 1200X. Always use a qualified electrician to install any necessary electrical equipment. To prevent the risk of shock or fire hazard, always check to see that the amplifiers are properly grounded.
INDUSTRIAL AND COMMERCIAL INSTALLATIONS
For commercial and other installations where sustained high-power operation is required, the amplifiers should be mounted in a standard 19” rack. It is not necessary to leave a rack space between each amplifier in the stack, since the fan pulls air in from the rear and exhausts the hot air out of the front. An adequate cool air supply must be provided for the amplifiers when rack- mounted. The internal fan must have a source of air that is not preheated by other equipment. The amplifier will start up in low-speed fan operation and will normally stay at low-speed opera- tion unless sustained high-power operating levels occur. As the amplifier heat sinks heat up, the automatic thermal-sensing circuitry will cause high-speed operation to occur. Depending upon signal conditions and amplifier loading, high-speed fan operation may continue, or the fan may cycle continuously between high and low. This situation is quite normal. If cooling is inadequate due to preheated air, or a reduction of air flow occurs due to blockage of the inlet or outlet ports, or if the amplifier is severely overloaded or short-circuited, the internal thermal-sensing system may cause temporary shutdown of that particular channel. Depending upon the availability of cool air, operation should be restored in that channel relatively quickly. In any case, corrective action should be taken to determine the cause of the thermal shutdown. If the amplifier is not severely overloaded or short-circuited, and air flow is normal in the amplifier, steps should be taken to provide a cooler environment for all the amplifiers. As a general rule, the cooler elec- tronic equipment is operated, the longer its useful service life will be.
