The Megger MS-2A test set is used around the world by
several thousand utility companies, industrial plants and
electrical service organizations.
Model MS-2A is a self-contained test set that incorporates a
variable high-current output and appropriate control
circuitry and instrumentation for testing thermal, magnetic
or solid-state motor overload relays, molded-case circuit
breakers, ground-fault trip devices and overcurrent relays.
Model MS-2A is capable of testing the time-delay
characteristics of overcurrent relays, motor overload relays
and molded-case circuit breakers rated up to 125 amperes,
when following the recommended test procedure of testing
the time delay of these devices at three times their rating.
Higher currents are available for the short durations
required to test an instantaneous trip element. For
example, the test set will provide a maximum shortduration output of 750 amperes through a typical,
125 ampere, molded-case circuit breaker.
The MS-2A is ideal for testing ground fault protection
devises with window CT’s. The NEC 230.95C requires
specific ground fault devices be performance tested when
The MS-2A is commonly used by many utilities and service
organizations as a economical light weight overcurrent
relay test system.