Resistance tester TRM 104

stator windingfor transformersportable

TRM104 is a portable winding resistance meter, designed to work in live EHV switchyards. Winding resistance values of large transformers up to 500 MVA and rotating machines are directly displayed. The meter is protected against the back emf offered by large inductive winding. A back-lit 4 line LCD with a user-friendly menu sets up the instrument for the test. Winding resistances and safety messages are also shown on this display. It is possible to measure the resistance of two windings simultaneously.The meter contains a special power source for rapid stabilization of test results. A 30V DC, 10 Amp power source, controlled strategically by digital means passes the selected current through the winding. Precision instrumentation amplifiers read voltage developed across the windings and the ohmic values are directly displayed. Use of the classical Kelvin’s 4-wire method ensures reliable measurement. Specially designed thermal management of power source enables measurement over longer periods, when delta connected generator transformers are tested. The TRM is capable of identifying the interruption of injected current during tap change of OLTC. A beeper alarm during current injection ensures operator safety during measurement. Winding resistance values of large transformers upto 500 MVA and rotating machines are directly displayed. Portable winding resistance meter, designed to work in live EHV switchyards. Protected against the back emf off ered by large inductive windings. A backlit 4 line LCD with a user-friendly menu sets up the instrument for the test. Winding resistances and safety messages are also shown on this display.