Specifications

June 2007 PIP ELSAP20
Low-Voltage Automatic Transfer Switch
owner: The party that owns the facility wherein the low-voltage automatic transfer switch
will be used.
purchaser: The party who awards the contract to the supplier. The purchaser may be the
owner or the owner’s authorized agent.
supplier: The party responsible for providing the low-voltage automatic transfer switch.
4. Requirements
4.1 General
4.1.1 Unless otherwise specified on the purchaser’s PIP ELSAP20D Data Sheet,
the automatic transfer switch shall be mounted indoors.
4.1.2 If specified on the purchaser’s PIP ELSAP20D Data Sheet, the automatic
transfer switch shall include a bypass-isolation switch.
4.1.3 Unless otherwise specified on the purchaser’s PIP ELSAP20D Data Sheet,
the automatic transfer and bypass-isolation functions shall not use molded
case circuit breakers, or contactors.
4.1.4 The automatic transfer switch and bypass-isolation switch shall be
completely factory interconnected and tested so that only the line and load
connections to the bypass-isolation switch are required for field installation.
4.1.5 Unless otherwise specified on the purchaser’s PIP ELSAP20D Data Sheet, all
interconnections between the transfer switch and bypass-isolation switch
shall be silver plated copper bus bar.
4.1.6 Switch shall be dead front construction.
4.1.7 Microprocessor based controller(s) shall provide sensing, controlling, and
logic programming for the automatic transfer switch.
4.1.8 Automatic transfer switch and bypass-isolation switch shall be in accordance
with NEMA ICS-10.
4.1.9 Automatic transfer switch, complete with bypass-isolation switch and all
accessories, shall be UL listed and labeled in accordance with UL 1008.
4.1.10 Automatic transfer switch shall have internal mechanical ground connections
suitably sized for terminating stranded copper ground conductors.
4.1.11 Ground connections shall be located near incoming and outgoing power
cable termination points.
4.2 Transfer Switch
4.2.1 Transfer switch shall be rated as specified on the purchaser’s PIP ELSAP20D
Data Sheet.
4.2.2 Automatic transfer switch shall be rated to close on, and withstand, the RMS
symmetrical short circuit current specified on the purchaser’s
PIP ELSAP20D Data Sheet.
4.2.3 Unless otherwise specified on the purchaser’s PIP ELSAP20D Data Sheet,
the automatic transfer switch shall be “open transition” type.
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