Power blocks get tough with harsh environments
From Powersolve comes the TEQ 300WIR family of ruggedised DC-DC converters designed to offer the highest performance in harsh environments.
The power blocks are approved to safety standards IEC/UL 60950-1 and UL 508 as well as meeting the requirements of EN 50155 and EN 61373 which makes them suitable for railway applications.
Made by Traco, TEQ 300WIR units feature extra wide input voltage ranges of 18 to 75VDC and 43 to 160VDC. Interestingly, the nominal input voltages of 48, 72, 96 and 110 VDC can be applied while a ±40 per cent deviation of nominal input voltage does not affect the function. This means that the power blocks can cope permanently with brownouts (0.6 x Vnom x 100ms) and transient voltages (1.4 x Vnom x 1s) as defined by EN50155.
The units are available with output voltages of 12, 15, 24, 28 and 48VDC, which are adjustable by ±20%.
The TEQ 300WIR models provide a reinforced I/O insulation for an isolation voltage of 3000 VAC (1 min test voltage). The output characteristic is “constant voltage to constant current” (CV/CC) which means that the output voltage is stable up to a load current of about 110 per cent 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 features that make these converters reliable and fail-save, says Powersolve.
Sense line inputs are available to compensate the voltage drop at long wires to the load and the converter and have a load share function for parallel operation of up to three units or for a true redundant operation.
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 equipment” 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.
Operating across the temperature range of -40 degrees C to +80 degrees C, these converters pass cyclic damp heat and dry heat tests without developing any physical damage.
In addition, the products meet the fire resistant requirements according to EN 45545-2.