Vanguard DigiTMR S2 - Manual (Page 7)

REV 1 DIGITMR S2 USER’S MANUAL
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1.0 INTRODUCTION
1.1 General Description and Features
The Vanguard DigiTMR S2 is an inexpensive, easy to use digital circuit breaker analyzer. The
DigiTMR S2 can be operated stand-alone or can be computer-controlled. It can fully analyze a
circuit-breaker’s performance by testing the contact time, stroke, velocity, over-travel, and
contact wipe. Contact and motion analysis can be performed for all breaker contact operations
(Open, Close, Open – Close, Close – Open, and Open – Close – Open). Timing results are
recorded and displayed on the 240 x 128 pixels back-lit LCD screen and can also be printed on
the built-in 4.5" wide thermal printer.
“On-Line” Timing Mode
In addition to the conventional off-line timing mode, the DigiTMR S2 also offers an optional
“on-line” timing mode. In this mode, the DigiTMR S2 captures the breaker’s trip or close time,
the trip/close coil current “fingerprint,” and the battery supply voltage while the breaker is still
in service. The trip/close time is derived from the time of trip, or close coil initiation, to the
breaker’s bushing current breaker-make as detected by an AC clamp-on current sensing probe.
The “on-line” timing mode can detect a breaker’s operating conditions with little or no down
time. In this mode, the first trip operation time of the breaker is captured. If a breaker has been
in service for a long period of time and sitting in close position, the first trip time of the breaker
may be slow possibly due to a sticky mechanism. The “on-line” mode is very useful in such
cases because traditional breaker timing may not detect this condition since several operations
may have occurred before the first timing test is conducted.
Diagnostic Capabilities
The DigiTMR S2 can perform diagnostics on its internal electronics. Diagnostics can be
performed to verify contact cable connections and to test the travel transducer's electronics.
Open/Close Coil Current Monitoring
A built-in Hall-Effect current sensor records the circuit breaker’s operating coil current
amplitude and duration. The circuit breakers’ operating-coil waveforms (effectively, a
performance “fingerprint” or “current profile”) can be used as a diagnostic tool for analyzing a
circuit breaker’s performance.
Internal Test Record and Test Plan Storage
The DigiTMR S2 can store up to 200 test records and 100 circuit breaker test plans in Flash
EEPROM. A test plan comprises of all circuit breaker performance specifications (Stroke,
Velocity, and Contact Time). When a test plan is used, the DigiTMR S2 compares the test results
for the circuit breaker against its performance to generate a “Pass/Fail” report.
Test plans are generated using the included Windows®-based Circuit Breaker Analysis
application. Test plans can be transferred to the DigiTMR S2 via the USB or optional Bluetooth
interface, or by using an external USB Flash drive. Up to 999 test records and 999 test plans can
be stored on an external USB Flash drive.