MGE UPS Systems EPS 7000 user manual Power Flow Diagrams Normal Operation, On-Battery Operation

Users Manual

1.4.2 Power Flow Diagrams

1.4.2.1 Normal Operation

During normal operation, power flows from the main AC input source (mains 1) into the UPS rectifier/battery charger section. The rectifier/battery charger converts the AC voltage to DC, maintains the charge of the battery, and feeds the DC power to the inverter. The inverter regenerates AC voltage, and supplies the attached load. See Figure 1-5.

Figure 1-4: Normal Operation, Power Flow Diagram.

Static switch

Bypass AC input (mains 2)

Rectifier/battery	Inverter
charger

Main AC input (mains 1)

Attached load(s)

Battery

1.4.2.2 On-Battery Operation

If the main AC input source (mains 1) fails or goes out of tolerance, the charger stops. Power flows from the battery to the UPS inverter, which in turn supplies the attached load. When the main AC input source (mains 1) returns, the charger restarts automatically and the UPS resumes its normal operation. See Figure 1-6.

If the battery becomes depleted before the main AC input source (mains 1) returns, the inverter stops and the attached load is transferred to the bypass AC input source (mains 2) if it is available.

Figure 1-5: On-Battery Operation, Power Flow Diagram.

Static switch

Bypass AC input (mains 2)

Rectifier/battery	Inverter
charger

Main AC input (mains 1)

Attached load(s)

Battery

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