(Image courtesy of TDK-Lambda).
TDK Corporation announces the TDK-Lambda brand EVS constant current AC-DC power supplies. The board style 300W rated models can operate without forced air cooling, with the enclosed 600W models having an internal cooling fan. These five-year warranty power supplies are ideal for charging batteries in energy storage systems, or for other applications requiring constant current outputs such as water purification or plating.
The EVS series will accept a wide 85 to 265Vac input and has nominal 18V (300W only), 36V and 57V outputs for use with 12V, 24V and 48V lithium ion, nickel hydride and lead acid batteries. The float voltage is user adjustable down to the nominal battery voltage and the charging current can set from 50% to 100% of the rated current. Parallel operation is possible.
The units can operate in ambient temperatures ranging from -20 to 70oC with model dependent derating. The 300W supplies measure 3.31" x 1.65" x 7.09" and have an optional perforated cover, with the 600W measuring 4.72" x 2.4" x 7.48". A remote on/off function can also be selected on both power levels.
An external stand-alone reverse protection module is also available, preventing backflow of current into the power supply from the battery. Rated at 20A, 7 to 60Vdc, the EVS-RP6020 uses a low resistance MOSFET to reduce the voltage drop to less than 200mV. This module is available as a board assembly or with a mounting bracket, measuring 1.97" x 1.02" x 3.05" and 2.36" x 1.26" x 3.68" respectively.
The power supplies have 3kVac input to output, 2kVac input to ground and 500Vdc output to ground isolation. All are certified to UL/CSA/IEC/EN 60950-1 and carry the CE mark for the Low Voltage and RoHS2 Directives. The EVS complies with EN55011/EN55022-B conducted emissions and the IEC 61000-3-2 harmonics and IEC 61000-4 immunity standards.