Use These Special Installation Instructions For Floating Neutral Systems - GE 90-30 PLC Series Installation And Hardware Manual

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Use These Special Installation Instructions for Floating Neutral Systems

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The voltage surge devices must be rated such that the system is protected from power line
transients that exceed Line voltage + 100V +(N-PE)
The expression N-PE refers to the voltage potential between neutral and Protective Earth (PE)
ground.
For example, in a 240 Volt AC system with neutral floating 50V above earth ground, the transient
protection should be rated at:
2-26 Series 90-30 PLC Installation and Hardware Manual – August 2002
The input power terminals should be wired according to the instructions in the "AC Power
Source Connections" section of this chapter.
The factory installed jumper between terminals 3 and 4 of the Power Supply module must be
removed if using one of the Power Supplies that have this feature. See the "Overvoltage
Protection Devices" section of the "Power Supplies" chapter for details.
Voltage surge protection devices, such as MOVs, MUST be installed between the following
terminals:
From L1 to earth ground
From L2 (Neutral) to earth ground
240V + 100V +50V = 390V
MAX.
GFK-0356Q