Delta C2000 Series Manual page 5

Pay particular attention to the following points:
 After turning on the main power, do not remove the RFI jumper while the power is on.
 Make sure the main power is turned off before removing the RFI jumper.
 Removing the RFI jumper will also cut off the conductivity of the capacitor. Gap discharge may occur
once the transient voltage exceeds 1000V.
If the RFI jumper is removed, there will no longer be reliable electrical isolation. In other words, all
controlled input and outputs can only be seen as low-voltage terminals with basic electrical isolation. Also,
when the internal RFI capacitor is cut off, the Power Regenerative Unit will no longer be electromagnetic
compatible.
 The RFI jumper may not be removed if the main power is a grounded power system.
 The RFI jumper may not be removed while conducting high voltage tests. When conducting a high
voltage test to the entire facility, the main power and the motor must be disconnected if leakage current
is too high.
Floating Ground System(IT Systems)
A floating ground system is also called IT system, ungrounded system, or high impedance/resistance
(greater than 30Ω) grounding system.
Disconnect the ground cable from the internal EMC filter.

In situations where EMC is required, check whether there is excess electromagnetic radiation affecting

nearby low-voltage circuits. In some situations, the adapter and cable naturally provide enough
suppression. If in doubt, install an extra electrostatic shielded cable on the power supply side between
the main circuit and the control terminals to increase security.
Do not install an external RFI/EMC filter, the EMC filter will pass through a filter capacitor, thus

connecting power input to ground. This is very dangerous and can easily damage the Power
Regenerative Unit.
Asymmetric Ground System(Corner Grounded TN Systems)
Caution: Do not remove the RFI jumper while the input terminal of the Power Regenerative Unit carries
power.
In the following four situations, the RFI jumper must be removed. This is to prevent the system from
grounding through the RFI capacitor, damaging the Power Regenerative Unit.
1 Grounding at a corner in a triangle configuration
RFI jumper must be removed
2 Grounding at a midpoint in a polygonal
configuration
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L 2
L 3
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Chapter 1 IntroductionC2000 Series
L 1
L 2
L 3