Emerson Liebert Static Transfer Switch - Manual (Page 98)

Liebert STS2 Touch Screen Display
90
Figure 53 User settings dialog box
Source Set Points
The Source 1/2 Set Points allows you to configure trigger points for each input source (1 or 2) for the
Liebert STS2 via a keypad dialog or HI/LO dialog box. The source numbers do not designate the
source as the preferred or alternate source. The numbers simply identify the input source. See 10.2 -
Manual Transfer / Preferred Source Selection to set the preferred source.
The Set Points are based on values in relation to the nominal voltage required for the Liebert STS2.
UV refers to under voltage, meaning the amount of voltage below the nominal voltage. OV refers to
over voltage, or the amount of voltage over the nominal voltage.
• Fast UV Setting (%) — if the voltage drops below this set percentage of the nominal voltage, the
Liebert STS2 transfers from the current source to the opposite source.
• Slow UV Setting (%) — if the voltage remains this set percentage below the nominal voltage for
the period of the slow detection delay, the Liebert STS2 transfers from the current source to the
opposite source.
• Slow UV detection delay — the number of cycles that the source must remain below the Slow UV
Setting before the Liebert STS2 transfers.
• OV Setting (%) — if the voltage exceeds this set percentage of the nominal voltage for the period of
the OV detection delay, the Liebert STS2 transfers from the current source to the opposite source.
• OV Detection Delay — the number of cycles that the source must remain above the OV Setting
before the Liebert STS2 transfers sources.
• I-PK Xfer Lockout — if current from the source exceeds this threshold, the Liebert STS2 disables
source transfers, and has to be reset either manually or automatically. The type of reset is config-
ured under the User Settings.