American Power Conversion 400 user manual Test button functions 5.2.1 Line Voltage bar graph

5.0 Operation

5.2Test button functions 5.2.1 Line Voltage bar graph

When you press and release the rear-panel Test button, the LED front-panel indicators display a bar graph of the input line voltage connected to the UPS.

UPS version			Input Vac
120 Vac	104	110	116	122	128
100 Vac	90	96	102	108	114
220/230/240	210	221	232	245	257

This example shows the input line voltage is between 116 and 122 Vac (120 Vac UPS, see table for other versions).

If no indicators light and the UPS is plugged into a known working outlet, the line voltage is extremely low. Low voltage could be the result of an overloaded branch circuit, a misadjusted service pole transformer, or an intentional local service brownout. The UPS compensates for this problem using SmartBoost to increase the supplied load voltage.

If all five indicators light, the line voltage is high and should be checked by a qualified electrician.

Note: After approximately 4 seconds, the UPS beeps and replaces the Line Voltage

bar graph with the Output Voltage bar graph display (see Sec. 5.2.2).

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