Modular Test Plug For Voltage, Current And Current Transformer Saturation Testing

Abstract

A modular test plug for voltage, current and saturation testing has a housing having a handle portion, a plurality of jaw connections for injecting upstream toward the equipment to be tested, a plurality of blade connections for injecting downstream toward a transformer, a first plurality of binding posts on a top of the housing connected to the jaw connections, and a second plurality of binding posts also on a top of the housing connected to the blade connections. Also provided is a short-defeating insert for defeating a shorting mechanism in an FT switch. This insert has a thin flat extension member extending from the body to prevent a bottom cam on a shorting blade from making contact with a shorting spring that would otherwise short the circuit when the switch handle is moved from the open position to the closed position.

What is claimed is: 
     
         1 . A modular test plug for voltage, current and saturation testing of electrical equipment, the modular test plug comprising:
 a housing having a handle portion at a rear of the housing;   a plurality of jaw connections extending from a front of the housing for injecting upstream toward the equipment to be tested;   a plurality of blade connections also extending from the front of the housing for injecting downstream toward a transformer;   a first plurality of binding posts on a top of the housing, the first plurality of binding posts being connected to the jaw connections; and   a second plurality of binding posts also on a top of the housing, the second plurality of binding posts being connected to the blade connections.   
     
     
         2 . The test plug as claimed in  claim 1  wherein:
 the plurality of jaw connections is arranged in a line and disposed above the plurality of blade connections; and 
 the first plurality of binding posts connected to the jaw connections is disposed forward of the second plurality of binding posts connected to the blade connections. 
 
     
     
         3 . The test plug as claimed in  claim 1  wherein the first plurality of binding posts comprises ten staggered binding posts for the jaw connections. 
     
     
         4 . The test plug as claimed in  claim 1  wherein the second plurality of binding posts comprises ten staggered binding posts for the blade connections. 
     
     
         5 . The test plug as claimed in  claim 1  wherein the first plurality of binding posts comprises ten staggered binding posts for the jaw connections and wherein the second plurality of binding posts comprises ten staggered binding posts for the blade connections, and wherein the ten staggered binding posts for the jaw connections are disposed forward of the ten staggered binding posts for the blade connections. 
     
     
         6 . A method for testing protective relays, meters and instruments using an FT switch, the method comprising:
 providing a test plug having a plurality of jaw connections and a plurality of blade connections;   injecting downstream toward a transformer using the plurality of blade connections; and   measuring one or both of current and voltage using one or more of a first plurality of binding posts that are electrically connected to the blade connections and to the transformer.   
     
     
         7 . The method as claimed in  claim 6  further comprising a step of injecting upstream toward the equipment to be tested. 
     
     
         8 . The method as claimed in  claim 7  further comprising measuring one or both of current and voltage using a second plurality of binding posts that are electrically connected to the blade connections; 
     
     
         9 . The method as claimed in  claim 6  comprising conducting a saturation test.