EA Technology CableData CDC2, Руководство по эксплуатации

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EA Technology CableData Collector Operating Manual 1365/L/01/1
Page 48 of 54
11.1.4 RFCT Connection Requirements
The RFCT detects the occurrence of a partial discharge between the line conductor and
earth by monitoring the condition of either of the three connection methods mentioned
below. The connection methods are shown in Figure 69. Connections can be made:
By monitoring the earth cable only (figure C), this is the preferred connection method.
By monitoring the line conductor without the earth (figure D) or,
By monitoring the line conductor and earth within the sheathing and the earth cable external
to the sheathing when passed back through the RFCT (figure F, close up Figure 70).
If the RFCT is placed over both the line conductor and earth cable at the same time the
discharge currents are cancelled. This is illustrated in figure E, the method to counter this
effect is shown in figure F, and figure G. Figure C shows the preferred connection method,
as the other connection methods should only be used for three phase cables, or single
phase cables with a light load.
Figure 69 - Cable Connection Methods
Earth Cable
RFCT
RFCT
Switch Gear
Housing
Earth Cable
Power Cable
Earth Cable
RFCT
RFCT
Earth Cable
Power Cable
Switch Gear
Housing