Atec Megger-MS-2A - Manual

MS-2A
Circuit Breaker and Overcurrent Relay Test Set
I Light Weight, Portable Primary Injection
Test Instrument
I Overcurrent Relay Testing
I Ground Fault Performance Testing
for NEC 230.95
I Circuit Breaker Testing
MS-2A
Circuit Breaker and Overcurrent Relay Test Set
DESCRIPTION
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.
APPLICATIONS
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 short-
duration 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
initially installed.
The MS-2A is commonly used by many utilities and service
organizations as a economical light weight overcurrent
relay test system.
Additional applications include verifying the ratio of
current transformers and testing panelboard ammeters
and voltmeters.
FEATURES AND BENEFITS
I Rugged and lightweight: Unit weighs only 33 lb
(15 kg) and is tough enough to withstand daily field
or plant use.
I Digital memory ammeter: High-accuracy, direct-
reading instrument has read-and-hold memory for
measurement of short-duration currents. Ideal for testing
ground fault devices, overcurrent relays and molded
case circuit breakers.
I Digital, multirange timer: Crystal-controlled, high-
accuracy instrument with autoranging measures
operating time to 1 millisecond.
I High-current output: Provides instantaneous currents
up to 750 amperes through a 125 ampere breaker in a
small 33lb (15kg) package
SPECIFICATIONS
Input
Input Voltage (specify one): 120 V OR 240 V, 50/60 Hz, 1 φ
Output
Output Ranges: The output is continuously adjustable in four
ranges to accommodate a variety of test-circuit impedances:
0 to 5 A at 120 V max.
0 to 25 A at 24 V max.
0 to 120 A at 6 V max.
0 to 240 A at 3 V max.