The P991 Test Block, designed as part of the MiCOM range, offers safe and configurable facilities for monitoring and secondary injection testing in any power system protection scheme when used with the P992 multi-finger Test Plug. A single-finger test plug is also available (type P993) that provides a safe and isolated means solely for the verification of CT circuits.
The P991 Test Block features visible automatic line CT shorting prior to the relay CT circuit being broken on insertion of a P992 multi-finger Test Plug. Up to three stages of sequential contact operation are provided by the P991 Test Plug. To avoid accidental tripping an extraction stop facility is included.
Provides monitoring and secondary injection test facilities
Mounted next to the protection relay - convenient 4U rack height
Monitors up to 14 circuits, each with a specific cassette to configure the action
Cassettes available for CT shorting, and staged-break and make operation when inserting and withdrawing the test plug
No need to disturb protection relay wiring when injection testing or troubleshooting
The cover provides protection from electrical shock hazards
UL-listed and CE-marked
Front of panel access
P991 test module with provision for 14 circuits (cassettes)
6 different cassette options are available
Test access is gained using P992 (multi-finger) and P993 (single-finger) test plugs
All test plugs keyed to avoid inverted insertion, or insertion in an incorrect cassette type
Overall differentiation factors
Testing is simplified and quickly performed
Single-finger test plug converts measured current to a safe voltage for measurement to avoid a dangerous open-circuit
Test wiring is prepared in advance on the P992 plug, prior to insertion - safer than step-by-step link-based test switches
CT short-circuiting is performed safely within the block, rather than at the test plug, to minimise the chance of human error
Grid Solutions, a GE Renewable Energy business, serves customers globally with over 15,000 employees in approximately 70
countries. With decades of expertise, Grid Solutions helps utilities and the industry at large effectively manage electricity from the point of
generation to the point of consumption, ensuring the reliability, efficiency and security of the grid. Grid Solutions is focused on bringing together technologies
and decades of expertise to help solve the toughest power system challenges, accelerating the global transition to a greener, more resilient and reliable grid.