Liebert II manual Voltage Ratings and Power Source Configurations, Electrical Connections

3.0ELECTRICAL CONNECTIONS

All electrical connections should be installed only by a qualified (licensed) electrician. All wiring must comply with the National Electrical Code (NEC) and applicable local codes.

! CAUTION

Verify that all power circuits are de-energized and locked out before making electrical connections.

3.1Voltage Ratings and Power Source Configurations

Before making connections to the unit, verify that the unit model number and nameplate voltage rating are appropriate for connection to the intended power source. See Table 3 for voltage rating applications with typical power source configurations.

Surge Voltage Ratings—To obtain the suppression voltage ratings (SVRs), as obtained by Underwriters Laboratory, Incorporated, in accordance with the Standard for Safety, Transient Voltage Surge Suppressors (TVSS), Standard 1449, Second Edition, dated August 15, 1996, marked on this product, #2 AWG wire must be utilized to connect the unit to your facilities’ power grid. Connections made with conductors other that #2 AWG may result in different SVRs.

Circuit Ampacity Limitations—Representative samples of this product have been investigated by Underwriters Laboratories, Incorporated to withstand, without exposing live circuits or compo- nents at system voltages and fault currents of up to 200,000 AIC, as described in the Standard for Safety, Transient Voltage Surge Suppressor (TVSS), Standard 1449, Second Edition, dated August 15, 1996.

3.2Parallel Connection (see Figures 2 and 3)

With parallel connection, the length of the wiring to the Transient Voltage Surge Suppressor (TVSS) unit must be minimized for best performance. Wires should be as short and straight as possible.

To reduce the wiring impedance to surge currents, the phase, neutral (if required), and ground conductors are recommended to be twisted together and routed in the same raceway (conduit). Avoid any sharp bends in the conductors.

Wire Sizing—With parallel connection, the size of the wiring to the TVSS unit is independent of the protected circuit’s ampacity. Suggested wire size based on the unit’s transient surge current capabilities are show in the table below.

Table 2	Suggested wire and breaker size
Model Series		Outline Drawing	Wire Size	Breaker Size
SI016 –SI025 Wire Lugs		82010	8-1/0	40A
SI016 –SI025 Disconnect		82011	8-1/0	40A
S0320 –SI050 Wire Lugs		82012	4-1/0	80A
S0320 –SI050 Disconnect		82013	4-1/0	80A
SI060 –SI075 Wire Lugs		82014	4-1/0	80A
SI060 –SI075 Disconnect		82015	4-1/0	80A
SI100 Wire Lugs		82016	4-1/0	80A
SI100 Disconnect		82017	4-1/0	80A

NEC Articles 280-21 and 22 require surge arrestor connecting conductors to be at least #14 copper or #12 aluminum.

Overcurrent Protection—The TVSS unit conducts practically no current under normal opera- tion and conducts only very short duration transient surge currents.

External overcurrent protection is not specifically required by NEC Article 280 nor is it desired since it impedes the performance of the transient voltage surge suppressor. If fusing is required, please consult factory for recommendations.

4Electrical Connections