Datasheet

12
Installation and Operation Manual
General The SPD device has SPD components connected from phase to ground. To
prevent hazardous touch voltage on the SPD enclosure during normal
operation or during SPD end-of-life, it is critical that there be a robust and
effective connection to the building grounding structure. The grounding
connection must utilize an equipment grounding conductor run with the phase
and neutral (if present) connection of the power system. The SPD device
should not be connected to a separate isolated ground.
When metallic raceway is used as the wiring method, an insulated grounding
conductor should be run inside the raceway and sized in accordance with all
applicable codes. Maintain electrical continuity at all raceway connections using
appropriate bonding devices and do not install isolating bushings to interrupt a
metallic raceway run.
For best overvoltage suppression by the SPD device, use a single-point ground
system where the service entrance grounding electrode system is connected to
and bonded to all other available electrodes, building steel, metal water pipes,
driven rods, etc. (for reference, see IEEE 142-2007). The ground impedance
measurement of the electrical system should be as low as possible, and in
compliance with all applicable codes.
Power System Grounding In addition to the power system configuration and voltage, the power system
grounding method must be considered when selecting the appropriate SPD.
Refer to the following chart to determine the appropriate power system
grounding method.
Solidly-Grounded Power System
SPDs rated for use on solidly-grounded power systems must not be connected
to resistance-grounded (for example, HRG) or ungrounded power systems.
Such a connection can result in damage to the SPD within the SPD product.
Always verify the power system grounding configuration prior to application of
power to the SPD device. Confirm that all ground bonds are installed at both the
service entrance equipment and power system transformer prior to application
of power.
Table 4: Grounding Methods
Panel Mount Series SPDs Power System Grounding Method
All Panel Mount Products Solidly-Grounded
CAUTION
SPD DAMAGE AND POWER SYSTEM OVERVOLTAGE
• Do not connect SPDs rated for use on solidly-grounded power systems
to resistance-grounded (for example, HRG) or ungrounded power
systems.
• Verify that the serviced entrance equipment is bonded to ground in
accordance with all applicable codes.
• Verify that the neutral terminal of the power system transformer feeding
the EMA product is bonded to system ground in accordance with all
applicable codes.
Failure to follow these instructions can result in equipment damage.
Grounding