Using The Rtxp Test Switch - ABB RET650 Series Commissioning Manual

Section 4
Starting up
• Polarity check
• VT circuit voltage measurement (primary injection test)
• Grounding check
• Phase relationship
• Insulation resistance check
The polarity check verifies the integrity of circuits and the phase relationships. The check must be
performed as close to the IED as possible.
The primary injection test verifies the VT ratio and the wiring all the way from the primary system
to the IED. Injection must be performed for each phase-to-neutral circuit and each phase-to-phase
pair. In each case, voltages in all phases and neutral are measured.
4.9

Using the RTXP test switch

The RTXP test switch is designed to provide the means of safe testing of the IED. This is achieved
by the electromechanical design of the test switch and test plug handle. When the test plug handle
is inserted, it first blocks the trip and alarm circuits then it short circuits the CT secondary circuit
and opens the VT secondary circuits making the IED available for secondary injection.
When pulled out, the test handle is mechanically stopped in half withdrawn position. In this
position, the current and voltage enter the protection, but the alarm and trip circuits are still
isolated. Before removing the test handle, check that no trip or alarms are present in the IED.
Not until the test handle is completely removed, the trip and alarm circuits are restored for
operation.
Current circuit
1. Verify that the contacts are of current circuit type.
2. Verify that the short circuit jumpers are located in the correct slots.
Voltage circuit
1. Verify that the contacts are of voltage circuit type.
2. Check that no short circuit jumpers are located in the slots dedicated for voltage.
Trip and alarm circuits
1. Check that the correct types of contacts are used.
34
Verify that the contact sockets have been crimped correctly and that they are fully
inserted by tugging on the wires. Never do this with current circuits in service.
© Copyright 2013 ABB. All rights reserved
1MRK 504 136-UUS B
GUID-F1E29C06-7FE8-44D8-AD5A-EE8990A2AA41 v3
Transformer protection RET650
Commissioning manual