Bypass Mode; Manual Bypass Mode - Delta DPH Series User Manual

3.3

Bypass Mode

When the inverter encounters abnormal situations such as over temperature, overload, short
circuit, abnormal output voltage or low battery, it will automatically shut itself down. If the
UPS detects the bypass input is normal, it will automatically switch to Bypass mode to protect
the connected critical loads from power interruption. After the above-mentioned
abnormalities are eliminated, the UPS will switch back to On-Line mode from Bypass mode.
During Bypass mode, the UPS's tri-color LED illuminates yellow and the text 'Bypass'
appears in the upper right corner of the LCD screen
3.4

Manual Bypass Mode

When the UPS runs in Manual Bypass mode, the current only flows through the maintenance
bypass so that the maintenance personnel can maintain the circuit inside the UPS. However,
DO NOT touch any external maintenance bypass cabinet's terminal and bus bar which may
carry high-voltage electricity. During Manual Bypass mode, the UPS's input power is
completely cut off, and the critical loads are not protected. At the moment, the UPS's tri-color
LED and LCD screen are both off.
(Figure 3-3: Bypass Mode Diagram)
(Figure 3-4: Manual Bypass Mode Diagram)
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