Epilson STSTM

1.4.1PMM2 Plus and PMM2 Ultra

In the PMM2 Plus configuration, the input of the PMM2 cabinet is supplied by the output of the STS. The dual input distribution system accepts two independent AC input sources feeding to the STS. If the preferred input source power is not available, the STS will transfer to the alternate input source, avoiding interruption to the critical load. The output power is conditioned and stepped down to distribution voltage via an isolation transformer, feeding panelboards or main frame circuit beakers.

In the PMM2 Ultra configuration, an isolation transformer feeds each STS input source upstream of the STS. The transformer secondary output of the PMM2-1 (left cabinet) supplies the Source-1 input and PMM2-2 (right cabinet) supplies Source-2 input of the STS cabinet. If the preferred source input power is not available, the STS will transfer to the alternate input source, avoiding interruption to the critical load. The output of the STS connects to the output busbars of the PMM2-1 and PMM2-2 cabinets, feeding panelboards or main frame

Figure 1-2: PMM2 and PMM2 Ultra Cabinets.

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Introduction

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