Suitable for Emergency, Peak and Prime Power System Applications Low Voltage Automatic Transfer Switch Systems THE POWER AUTHORITY
THE POWER AUTHORITY ASCO’s experience and commitment to excellence in designing and building Emergency Power Control Systems for any application has made us the premier manufacturing and service organization in the world. For over 100 years we have built upon a tradition of providing our customers a full range of high performance and quality products. ASCO’s experience spans the history of the power control industry and since 1888 we have set the standard for the entire industry.
Automatic Transfer Systems Product Overview Content Page Service Entrance Rated Transfer System ............................................. 4 ATS Switchboard .................................................................................. 5 Two Source Automatic Transfer System .............................................. 6 Three Source ATS System .................................................................... 7 Three Source Priority System ..................................................
Service Entrance Rated Transfer System ASCO service entrance rated transfer systems are designed for automatic switching of loads between the utility source and an alternate source of power. The transfer system also contains a disconnect device on the normal source, plus a disconnect link on the utility neutral, and a disconnect link between neutral and ground.
ATS Switchboards An automatic transfer switchboard is a switchboard containing two or more automatic transfer switches in a common line-up. The switchboard shown in figure 5 contains two ASCO 962, 2000 ampere, automatic transfer bypass-isolation switches with circuit breakers on the normal and load side of each switch. An ammeter and voltmeter are also located on the load side of each switch. Fig. 5 Automatic transfer switchboard.
Two Source Automatic Transfer System ASCO two-source systems are designed for automatic switching of loads between the utility source and an alternate source of power. Upon the loss of the utility power source, the system provides an automatic start signal to the alternate source of power. Once the alternate source has reached proper voltage and frequency, the system transfers the critical load from the utility source to the alternate power source.
Three Source Automatic Transfer System ASCO three-source systems are similar to ASCO twosource systems except that a second alternate power source is added to back up the first if that power source fails. Upon the loss of the utility power source, the system provides all necessary controls to start both alternate power sources. The critical loads are automatically transferred to the first alternate power source that achieves acceptable voltage and frequency.
Three Source Priority System Fig. 11 Three source priority system. ASCO three-source priority systems are similar to the ASCO three-source systems except they protect two critical loads rather than one critical load. Upon the loss of the utility power source, the system provides all necessary controls to start both alternative power sources. The most critical load is transferred to the first alternate power source that achieves acceptable voltage and frequency.
Soft Load Transfer System ASCO soft load closed transition transfer switches provide a make-beforebreak transfer of a building load from a utility power source to an alternate power source. This system automatically brings the engine generator into synchronism with the utility source, then gradually shifts the load from the utility to the engine generator with virtually no voltage or frequency fluctuations.
Custom Applications Selective Load System Selective load systems allow one load at a time to be operated when normal power fails. The system uses the minimum amount of auxiliary power for operation so the alternate power source can be sized for only one load at a time. The selective load system can be designed to handle any number of loads in any combination of sizes to suit the customers needs. The only interfacing between the ASCO selective load system and the load controls are power cables.
Custom Applications Transfer Switch with Bottom Bus Risers Figure 17 shows a 4000 ampere transfer switch with bus risers for bottom entry bus duct on both the normal source and load connections. The emergency side of the transfer switch has lugs for cable connections from the top of the enclosure. This demonstrates our capability to meet custom service entry requirements. Fig. 17 Transfer switch with bottom bus riser.
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