Liebert POWER PROTECTION STATIC TRANSFER SWITCH Grounding, Electrical Requirements, Response Time

Specifications

15.1.4Grounding

Refer to 5.3 - System Grounding for specifications and instructions regarding grounding.

15.1.5Electrical Requirements

Table 19 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
	125% for 30 minutes 100A-400A
Overload Capability	125% for 10 minutes 600A-1000A
	150% for 2 minutes
	500% for 0.25 sec.

Table 20 Unit Short Circuit Withstand Capability

Unit Voltage	Unit Amps	Withstand Capability
	100-250A	100kA
208-240V
	400-600A	100kA
	800-1000A	100kA
	100-250A	65kA
380-480V
	400-600A	100kA
	800-1000A	65kA
	100-250A	25kA
600V
	400-600A	25kA
	800-1000A	42kA

15.1.6Input Surge Suppression

The STS2 is equipped with transient voltage surge suppression on each input for maximum surge suppression. The surge suppression is capable of protecting the STS2 from operating outside of toler- ances 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.

15.1.7Response Time

A dual level fast/slow transfer threshold is used for under voltage detection to allow the 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.

15.1.8Environmental Requirements

See 3.0 - Location Considerations for details concerning environmental requirements for the STS2.

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