ABB RELION 670 Series Technical Manual page 1371

1MRK 502 066-UUS B
Indicates to the IED that the injection on X82 is blocked. The reason for blocking is indicated
in the REX060 LCD.
• SAT_NO on X81 pin 6:
Indicates to the IED that there is a risk of saturated amplifier on voltage and/or current
output at X81, indication is also given in the REX060 LCD.
• COMMON on X81 terminal 7:
Common return for X81 terminal 5 and 6
Power status
• X11 terminal 3:
Fail, power off NC
• X11 terminal 1:
Ready, power off NO
• X11 terminal 2:
Common
23.3 Coupling capacitor unit REX061
23.3.1 Introduction
REX061 isolates the injection circuit from the rotor exciter voltage.
The REX061 coupling capacitor unit grounding point and grounding brush of the rotor shaft
should be properly interconnected.
23.3.2 Design
Measure points are added to the capacitor box that enables the measuring of rotor voltages
without any connection to a hazardous voltage, by the use of protective impedance. This enables
the usage of standard oscilloscope or handheld DVM.
Technical manual
The measure ports cause an additional rotor impedance of 20 MΩ per terminal to
ground. However, the rotor calibration procedure extracts this impedance.
Section 23
Injection equipment hardware
GUID-39A03C0F-44DC-47DD-9D7E-66C8292CD3A8 v1
GUID-F7DCDF09-CB35-4C6C-8623-4285BDB39E15 v1
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