INSTALLATION
Rack Mounting
The SPA Series amplifiers are designed for standard 19” rack mounting as well as “stack” mounting without a cabinet. Use 4 screws and washers for mounting to the front rack rails. It is also a good idea to support the amps also in the rear, especially for mobile use where the amps will be subjected to shocks.
Amplifier Cooling
Also pay close attention to the cooling requirements. Since the airflow is from the rear to the front, it is important to keep both the inlet in the rear and the output in the front clear of obstructions to enable efficient cooling airflow. Since the amp exhausts to the front it does not contribute to heat buildup in the rear of the rack. It is important, however, that the other devices used in the rack allow plenty of cool air in the rear to enable proper cooling of the amp. Never block the air vents in the sides and front of the amplifier if the load seen by amplifier is less than 4 ohms and the amplifier is being run at high output levels. For best results, in such high output power applications you should augment the amplifier’s air flow with a rack cooling system.
Internal Fuse Protection
Each of the SPA Series amplifiers has backup internal fuse protection on each channel on the secondary output circuitry of the power transformer. In almost all cases of power overload the external back panel circuit breaker, which is wired in the primary power input circuit of the power transformer, will trip before the internal fuses blow. Nevertheless, these fuses are valuable in that they can sometimes isolate the problem to a single channel, allowing operation of the other channel. Also, because they require added effort to rectify, they increase the vigilance of the operator in correctly eliminating the cause of the overload problem before further use. These fuses are located inside the units and require removal of the top of the chassis.
CAUTION: Never open the unit when connected to AC power as you can be severely shocked resulting in serious injury or even death. Please wait at least 5 minutes after disconnecting the unit from AC power to let any internal capacitors discharge before opening. )
Replace the fuse with the same type, size and power rating as noted in the illustration for your SPA Series amp. If it continuously blows, stop replacing the fuse and refer servicing to qualified personnel.
Internal Fuses for SPA 850/1400
SPA 850 10A/250V (x2)
SPA 1400 12A/250V (x2)
both 3AG Fast Blow
Internal Fuses for SPA 2400
SPA 2400 25A/250V (x2)
both 3AG Fast Blow
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