Every four to six years
•
Periodic maintenance test for protection IEDs of objects with redundant
protection system.
First maintenance test should always be carried out after the first
half year of service.
When protection IEDs are combined with built-in control, the test
interval can be increased drastically, up to for instance 15 years,
because the IED continuously reads service values, operates the
breakers, and so on.
12.2.1
Visual inspection
SEMOD56525-5 v3
Prior to testing, the protection IEDs should be inspected to detect any visible
damage that may have occurred (for example, dirt or moisture deposits,
overheating).
Make sure that all IEDs are equipped with covers.
12.2.2
Maintenance tests
SEMOD56534-1 v1
SEMOD56528-5 v5
To be made after the first half year of service, then with the cycle as proposed
above and after any suspected maloperation or change of the IED setting.
Testing of protection IEDs shall preferably be made with the primary circuit de-
energized. The IED cannot protect the circuit during testing. Trained personnel
may test one IED at a time on live circuits where redundant protection is installed
and de-energization of the primary circuit is not allowed.
ABB protection IEDs are preferably tested by aid of components from the
COMBITEST testing system described in information B03-9510 E. Main
components are RTXP 8/18/24 test switch usually located to the left in each
protection IED and RTXH 8/18/24 test handle, which is inserted in test switch at
secondary testing. All necessary operations such as opening of trip circuits, short-
circuiting of current circuits and opening of voltage circuits are automatically
performed in the right order to allow for simple and safe secondary testing even
with the object in service.
12.2.2.1
Preparation
SEMOD56528-10 v2
Before starting maintenance testing, the test engineers should scrutinize applicable
circuit diagrams and have the following documentation available:
Section 12
1MRK 505 372-UEN A
Commissioning and maintenance of the fault clearing system
166
Busbar protection REB670 2.2 IEC
Commissioning manual
