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84 Legrand PDU User Guide
Reset Button
The reset button is located inside the small hole near the display panel on the PDU.
Pressing this reset button restarts the software of Legrand PDU without any loss of power to outlets.
The Legrand PDU can be reset to its factory default values using this button when a serial connection is
available. See
Resetting to Factory Defaults
(on page 465).
The following image illustrates the location of the reset button on Zero U models.
Legrand PDU's Energy Pulse LED
The energy pulse LED is located near the USB-B port on the front display panel.
The following image illustrates a Zero U model's panel.
It can be used as a simple interface in certification labs where they use an optical sensor to count the
number of pulses and compare it to the energy reading of a reference meter.
By default this LED is disabled. You need to enable and configure the energy pulse settings first before you
can use it for verifying the pulse output. See
PDU
(on page 64).
Circuit Breakers
Legrand PDU models rated over 20A (North American) or 16A (international) contain overcurrent protectors
for outlets, which are usually branch circuit breakers. These circuit breakers automatically trip (disconnect
power) when the current flowing through the circuit breaker exceeds its rating.
If a circuit breaker switches off power, the LCD display shows
open
. To find which circuit breaker is open
(trips), select Alerts or OCPs in the Main Menu. See
Operating the Dot-Matrix LCD Display
(on page 60).
When a circuit breaker trips, power flow ceases to all outlets connected to it. You must manually reset the
circuit breaker so that affected outlets can resume normal operation.
Depending on the model you purchased, the circuit breaker may use a button- or handle-reset mechanism.
Resetting the Button-Type Circuit Breaker
Your button-type circuit breakers may look slightly different from the images shown in this section, but the
reset procedure remains the same.
To reset the button-type breakers:
1. Locate the breaker whose ON button is up, indicating that the breaker has tripped.
