SMC LET-4000-RDM Primary Test Equipment

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AC Current Test Set up to 20 kA with Motorized Regulation
The LET-4000-RDM is designed to perform most of the primary tests that are necessary in substations commissioning.



It allows to perform with sufficient power, all the primary current injections to test the proper function and wiring of all the elements that compose the protection and measuring section in a substation.

The regulation system is based on a continuously variable motorized autotransformer (Variac) that supplies to a power transformer that delivers the high current outputs and isolate the main supply from the load. A built-in ammeter and a timer gives the information about the current value and the operation time of the relay or breaker under test.


Permanent current up to 4000A, 8KVA in 4 Ranges.
Made up of 2 units, control and power unit.
Built in digital ammeter 0.5% accuracy.
Built in digital timer resolution 1 ms.
Thermal and shortcircuit protection.
Motorized Variac.


Direct and motor overload relay test.
In general, primary tests including the complete loop, i.e., current transformer, leads, protective relay and circuit breaker.