300 Watt DC/DC power block

Jon Lawson

The TEQ 300WIR models are approved to safety standards IEC/UL 60950-1 and UL 508. With the compliance to EN 50155 and EN 61373 they also find place in the TRACO POWER ‘railway’ category.

With the extra wide input voltage ranges of 18-75 and 43-110VDC the nominal input voltages of 48, 72, 96 and 110VDC can be applied while a ±40% deviation of nominal input voltage does not affect the function.

It means that the converters can bear with brownouts (0.6 x Vnom x 100ms) and transient voltage (1.4 x Vnom x 1s) defined by EN50155 not only for a limited duration but permanently.

The TEQ 300WIR models are equipped with internal filters to conform to demanding electromagnetic interference requirements.

The constraints selected for electromagnetic field immunity, fast transient burst immunity and surge immunity correspond with the highest level for ‘railway rolling stock equipmen’ under performance criteria A (continuous operation within specified datasheet limits).

The converters are also designed and approved to endure shock and vibration requirements for rolling stock equipment according to EN 61373. Solid flanges allow for an easy, strengthen fixation.

The modules are equipped with vibration proof spring clamps for secure electrical connection.

With an excellent efficiency and highest grade components they reliably operate in an environment temperature range of -40°C to +80°C. They pass cyclic damp heat and dry heat tests without developing any physical damages. In addition the products are qualified to the fire behavior

of components according to EN 45545-2.

The TEQ 300WIR models provide a reinforced I/O insulation for an isolation voltage of 3000 VAC (1 min test voltage). They are available with output voltages of 12, 15, 24, 28 and 48VDC which are adjustable by ±20%.

The output characteristics is ‘constant voltage to constant current’ (CV/CC) which means that the output voltage is stable up to a load current of about 110% of nominal current.

At this point the voltage will be decreased while the current stays stable. This feature is useful to start motors, charge lead acid batteries or pull up capacitors of unlimited capacitance.

Protection against overheating, overload, short circuit, reversed input, overvoltage and input under-voltage, are other features that make these Traco Power converters very reliable and fail-save.

Sense line inputs are available to compensate the voltage drop at long wires to the load and the converter have a load share function for parallel operation of up to three units or for a true redundant operation. All these characteristics allow for a simple but reliable design.

The extended Traco Power railway category portfolio now comprises DC/DC converters for PCB -or chassis mount in the power range of 8 to 300 Watt.