GE Multilin 515 Locking and Testing System

GE Multilin 515 Locking and Testing System

Product Overview

Core functions

The 515 lockout and testing module is a specialized testing device for GE Multilin relays, with main functions including:

Provide trip locking, relay isolation, and testing functions;

By turning on the switch and inserting the test plug, it is possible to monitor the phase current and residual current from the primary CT, or inject current into the relay through the secondary injection testing equipment during debugging;

Ensure that the CT (current transformer) is short circuited during testing to avoid high voltage hazards, while also isolating the output circuit of the trip relay to prevent false tripping.

Main features 

Including a 14 pole switch group, the CT input automatically short circuits when the current switch is turned on;

Support injection of current in each phase, equipped with grounding terminals;

Intuitively isolate (disconnect) the output circuit of the trip relay and provide a protective cover;

Suitable for power and industrial scenarios, equipped with 515 test plugs.

Installation instructions

CT Connection and Safety Requirements

The module provides a short-circuit switch for connecting three-phase CTs and individual zero sequence ground fault CTs (or three-phase CTs used for residual ground fault detection);

Key safety point: The CT must be connected to the short-circuit side of the switch. When the CT switch is opened, the CT will be short circuited to avoid dangerous high voltage caused by CT open circuit.

PANEL MOUNT

The module consists of a metal chassis and a test switch, and needs to be installed by sliding it in from the front of the panel;

The panel needs to be cut according to the dimensions shown in Figure 3, and the module should be fastened by bending retaining tabs. If necessary, the accompanying # 8 screws and anti vibration nuts can be used for reinforcement;

After installation, fasten the front cover and rotate the fasteners at both ends by 1/4 turn to lock it in place;

There is a grounding screw at the bottom right corner of the module's rear side, which needs to be connected to the panel chassis grounding.

Operating instructions

Switch configuration and function

There are a total of 14 switches, divided into two categories:

6 single pole switches (terminals 1-6 and 15-20): used to isolate relay output circuits, disconnect trip and auxiliary circuits, and achieve trip locking;

4 sets of dual switches (terminals 7-14 and 21-28): corresponding to A-phase, B-phase, C-phase currents and grounding currents, each set of switches is used for CT short circuit, test current injection, and CT current measurement.

The working logic of each set of dual switches:

The first switch (such as terminals 7 and 21): regardless of the switch status, the terminals are always short circuited;

The second switch (such as terminals 8 and 22) adopts a "close first, then open" design. When closed, the terminals are short circuited, and when opened, terminals 8-22 are open and 22 and 7-21 are short circuited (to achieve CT short circuit).

Test process

Before testing: Disconnect the trip and auxiliary circuits to prevent accidental tripping, and then short-circuit the CT;

During testing: After turning on the switch, insert the test plug to inject signals or monitor CT current;

After testing: first close the CT switch to restore the normal operation of the relay, and then close the trip and auxiliary circuits.