American Power Conversion 250 A - Manual (Page 45)

ATS/Voltage
InfraStruXure Power Generation System 35
ATS Setup
Press E NTER when the selector arrow rests at the ATS Setup item to change the following settings:
Transfer Points The voltage-sensing point at which you would transfer to the other source, based on
voltage and frequency.
• S1-Utility: The input voltage reading for Source 1.
• Low: The low voltage limit that causes the ATS to switch from Source 1 to Source 2.
Press E NTER to change this setting.
• High: The high voltage limit that causes the ATS to switch from Source 1 to Source 2.
Press E NTER to change this setting.
• Other Settings: The settings on this screen determine when the source is OK, and
define the quality of the source. Press E NTER when the selector arrow rests at this item
to change the following settings or thresholds:
– Freq: The frequency cannot vary beyond this configured range (+/– x.xx Hz).
– Phase Balance: The percent voltage difference between two phases cannot exceed
this configured setting (%).
– Phase Sequence: The phase rotation (default is A-B-C) must match this configured
setting.
Transfer Setup The following settings can be changed in this menu:
• Open Xfers: Defines how long BOTH the Source 1 and Source 2 switches will be OFF
(open) during an open transfer (see page 8 for a definition of open transfers).
• Allow Closed: Enables/disables closed transfers (see page 8 for a definition of closed
transfers).
• Max Sync: The maximum time allotted for the ATS to attempt a closed transfer before
it performs an open transfer.
• ATS Delay Settings: The time delay settings that affect transfers and retransfers.
– Gen Start: The amount of time allotted between when the generator receives a start
signal and when the generator starts (default is 0).
– Line Stable: If the ATS switches to Source 2 after a failure in Source 1, and Source 1
is restored, the Line Stable setting is the amount of time (in seconds) allotted for
Source 1 to become acceptable before the ATS returns to it (default is 3 minutes).
– Min on Gen: The minimum time the generator must run before the ATS retransfers to
utility (default is 15 minutes).