The range of 2RMLG Test Blocks, housed within an Epsilon enclosure, offers facilities for monitoring and secondary injection testing of power system protection schemes in conjunction with the MMLB 01 multi-fingered test plug. The MMLB 02 is a single fingered test plug available for monitoring current flow in individual circuits connected through the test block. The 2RMLG Test Block has 14 pairs of spring loaded contacts which are linked to a terminal block positioned at the rear of the enclosure. The 2RMLG07 is coded to only accept the MMLB07 Test Plug which has connection terminals 21, 23, 25 & 27, internally – For typical application see Fig 4. The 2RMLG08 is coded to only accept the 2RMLB08 Test Plug which has internal pairs 1& 3, 5& 7, 9& 11 and 15& 17 shorted together internally – For typical applications see Figs 5, 6, 7 & 8. Each pair of contacts is normally closed completing the circuit through the test block when the associated protection equipment is in use. For testing purposes the test block can be assessed by removing the front cover. The 2RMLG 01 has a metallic probe attached to the front cover assembly which when withdrawn open circuits the 2 contacts at position 13 and 14. The main dc auxiliary supply to the protection scheme or relay can be wired to this circuit to prevent inadvertent