500W 45-154Vdc / 24Vdc Converter for Railway Rolling Stock Applications
PB315-24 Series: Is a family of 500W and 250W DC/DC converter design for rolling stock, railway applications. These converters operate from a 45-154Vdc input and supply a 24Vdc/20.8A or 24Vdc/10.4A output.
Natural convection with integral heatsink: Model PB315-24*-H (where * = input/output terminal code) employs an integral heatsink and nartural convection cooling. No additional heatsinking such as a cool plate is required. In free air conditions, this model is rated to 500W, output power at ambient temperatures up to 50C. The model PB315-24* does not include the integral heatsink. In free air conditions, this variant is rated to 250W output power at ambient temperatures up to 45C.
High resistance to pollution: Has an enclosed chassis with no air ventilation holes. It has no cooling fans. Also, the internal printed circuit boards are conformally coated. As a result, it has high resistance to contamination by dust or other pollutants.
Wide input voltage range: The PB315-24 are designed to operate from a 72Vdc, 96Vdc or 110Vdc supply from an accumulator battery as defined by EN50155:1996. It operates continuously from an input voltage of 45-154Vdc. This wide input voltage range allows a single model to be used on many different rolling-stock power sources. It also allows the unit to provide stable output voltage even with large dips in the input supply voltage, as can occur during locomotive engine starting.
High efficiency and low thermal stress
Has a typical full load efficiency of 90% and employs substantial heatsinking. Consequently, thermal stresses on power-dissipating components are low leading to high reliability and long life.
Five different styles of input/output terminals:
Can be fitted with screw terminals (S), cage clamp terminals(C), 6.4mm Faston terminals (F), a pluggable screw terminal block with screw flanges (P), or a circular MIL connector (M)
Input polarity reversal protection and high tolerance of input ripple:
A high voltage diode is included in series with the input to the unit. This diode prevents damage to the unit if input polarity is accidently reversed. It also allows the PB315-24 series to be supplied from a DC source with a large amount of AC ripple (15%) without stressing the input filtering components.
Input inrush current limiting:
Input inrush current is limited to a max of 25A at input voltage of 110Vdc. This inrush changes proportionally to the applied input voltage. Inrush current limiting prevents contact welding of circuit breakers or nuisance blowing of fuses supplying input power to the PB315-24
Input voltage lockout:
The PB315-24 will shut down if input voltage exceeds the permitted value.
Output overload protection:
The PB315-24 maintains constant output voltage up to the set current limit. After the current limit is exceeded the converter switches to constant output current mode. The constant current mode extends to short circuit on the output. There is no limit on the maximum load capacitance or overload duration apart from thermal limitations.
Output voltage droop sharing:
The output voltage of the PB315-24 series measured on the main output before the redundancy diode decreases linearly by between 1.0% and 1.5% from no load to full load. This voltage droop assists current sharing between multiple parallel-connected PB314-24 units