Eaton Electrical ASY0673, ASY0529, ASY0567, ASY0674 Shows the basic functional elements of the UPS

OPERATION

Off mode turns off the output and most internal circuitry. Within this mode, Sleep mode turns off all internal circuitry when AC line is not present and battery voltage drops to a low threshold. If AC input voltage is not present in Off mode, the user can direct the UPS to enter Sleep mode by selecting the Battery Protect (BP) feature (see “Removing Input Power” on page 79). When AC input voltage returns in the Off mode (caused by a low battery alarm condition), the UPS automatically recovers and, if the Auto Restart parameter is enabled, switches to Double Conversion mode. Auto Restart is enabled as a factory-default.

After a discharge and subsequent low-battery shutdown, the UPS automatically recovers from Sleep mode if the Auto Restart parameter is enabled.

Figure 53 shows the basic functional elements of the UPS.

Input

(utility) Power

EMI/RFI

Filter

Battery

Modules (parallel)

Line/Battery

Relay

		Isolation
Bypass Relay		Transformer
		(an option only
		provided
Input Power (boost)		on units
	DC/AC Power Inverter	manufactured
Converter		before 2009)
	Internal DC
	Power Bus
		Output Relay

Battery Charger

Capacitor Bank

Figure 53. Eaton 9170+ UPS Functional Block Diagram

78 Eaton 9170+ UPS (3–18 kVA) User's Guide S 164201393 Rev E www.eaton.com/powerquality