Specifications
112
15.1.4 Grounding
Refer to 5.3 - System Grounding for specifications and instructions regarding grounding.
15.1.5 Electrical Requirements15.1.6 Input Surge Suppression
The Liebert STS2 is equipped with transient voltage surge suppression on each input for maximum
surge suppression. The surge suppression is capable of protecting the Liebert STS2 from operating
outside of tolerances due to surges as defined by IEC 1000-4-5 (1.2/50uS surge, 2kV CM and 1kV DM)
as required under EN 50091-2.
15.1.7 Response Time
A dual level fast/slow transfer threshold is used for under voltage detection to allow the Liebert STS2
to be compatible with UPSs and generators. The voltage thresholds and the slow transfer delay time
is user-adjustable. The fast transfer delay time is less than 4 ms.
The over voltage detection uses a single threshold, with programmable level and delay time.
See User Settings on page 89 for instructions on configuring these settings.
15.1.8 Environmental Requirements
See 3.0 - Location Considerations for details concerning environmental requirements for the
Liebert STS2.
Table 18 Electrical requirements
Item Requirement
Maximum Continuous Current 100, 250, 400, 600, 800, 1000 amps
Load Power Factor Range 0.75 to 1.0, leading or lagging
Load Crest Factor Up to 3.5
Source Voltage Distortion Up to 10% THD with notches and ringing transients
Overload Capability
125% for 30 minutes 100A-400A
125% for 10 minutes 600A-1000A
150% for 2 minutes
500% for 0.25 sec.
Table 19 Unit short circuit withstand capability
Unit Voltage Unit Amps Withstand Capability
208-240V
100-250A 125kA
400-600A 150kA
800-1000A 100kA
380-480V
100-250A 100kA
400-600A 100kA
800-1000A 65kA
600V
100-250A 50kA
400-600A 25kA
800-1000A 25kA