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5.1.5 Bypass mode
When in the bypass mode of operation, the load is supplied power conditioned by the Isolation Unit. However, the load will not be protected from utility voltage sags, swells or blackouts. The UPS will automatically transfer to bypass operation when a failure occurs within the Electronics Unit. Detected EU failures include blocked fan, battery charger fault, overtemperature and welded main relay; see section 7.2 for a complete list of fault messages. The UPS will also automatically transfer to bypass if the EU separating screw is loosened (as if the EU were to be pulled off the IU). A manual bypass switch located on the EU is used when maintenance of the EU is required. In all cases, the UPS must be returned to
Local users are alerted to this mode of operation by visual and audible indicators. When in bypass, the UPS displays the reason for bypass (fan failure, EU switch actuated, etc.) and "beeps". The UPS alerts remote users to the bypass conditions via serial communications from the computer interface port.
5.1.6 Transfer between modes of operation
Transfer of load power to and from all modes of operation occurs synchronously with the utility voltage phase. See the Specifications section of this manual for transfer time ratings.
5.2 Display and Controls Operation
The UPS is equipped with a 2x16 character back lit liquid crystal display (LCD) and three button keypad user interface. The display is structured with five main menu screens and a default screen. Each main menu screen allows access to several
5.2.1 Default screens
The UPS’s mode of operation is displayed by the default screen. Important fault messages are also communicated by the default screen. The UPS will show the default screen and the main menu screens when the Menu key is successively pressed. The UPS will automatically show the default screen after there has been no keypad activity in the previous 3 minutes or whenever warranted by a change in mode of operation or failure. Examples of the most common default screens are shown at the left.
5.2.2 Main menu screens
The UPS will show the main menu screens when any default screen key is pressed or when the Menu key is successively pressed. The five main menu screens are show in order at the left.
The main menu screens allow access to screens that display operational choices or show information on UPS status, diagnostics,