Explained: Medium Voltage Load Banks
Medium voltage (MV) power supplies are now one of the most common load bank test applications. Many facilities require MV supplies to power their equipment and matched MV load banks are specified to ensure back-up power supplies are kept in optimum condition.
There are three main types of medium voltage load banks:
Low voltage (LV) load bank with a step-down transformer on a common skid
A common configuration mounts a three-phase step-down transformer and one or more load banks on a structural skid, as shown in the image below. The transformer secondary voltage on these skid mounted units are usually rated at 480 or 600 volts. These higher secondary voltages result in lower current, and will require less interconnect cabling when compared to designs that use 208 volt or 240 volt secondary voltage.
Load bank manufactures often install large step-down power transformers and LV load sections inside 20-foot and 40-foot ISO-style containers. Unlike skid-mounted models, containerized load banks can offer both resistive and reactive loads, typically with variable power factors. The capacity of the 0.8 PF medium voltage containerized load banks range between 2 to 5 MW and are perfectly suited to heavy-duty load test applications.
Direct Connection Solution
True direct connect medium voltage load banks accept medium voltage power directly onto their input busses, and do not require any step-down transformers. The absence of transformers allows any additional space to be dedicated to increasing kW capacity. While typically offered in capacities up to 6000 kW, these units can sometimes offer higher capacities (depending on the application and the required voltages).
Subscribe to our mailing list to receive our latest educational insights and industry perspectives.