Power Management

RTL has designed a load control distribution box (LCDB) that provides intelligent power management capabilities for a 28VDC vehicle power distribution system. The system has up to seven individually controlled channels that may be energized or de-energized using a relay. Each channel has the capability to detect and report malfunctions such as:

  • Electrical shorts
  • Open circuits
  • Under voltage
  • Over voltage
  • Over current

The LCDB is composed of the following:

  • Controller card: controls decision making and communication with external systems
  • Power channels: delivers power to the equipment and allows power management by proving information on the current and power delivered and the ability to connect or disconnect each channel
  • Interface card: provides interfacing, logic, signal conditioning and drivers allowing the control card to interface with the power channels


  • Channel capacity: up to 450 amps
  • Power management: handles real-time power and current flow though the LCDB maintaining stability, preventing overloads, and reporting faults
  • Prioritization: when current demand exceeds the supply capacity of the system, the lowest priority channel or channels will be disconnected to rebalance the power system supply and demand
  • Channel short-circuit protection: in the event of a short-circuit condition, the system will open channel relay and report a channel fault via a solid red LED light
  • Channel voltage protection: if input voltage to the LCDB exceeds 32 VDC or falls below 20 VDC for a fixed period, the system will open all channel relays and illuminate all red LED lights. If voltage exceeds 40 VDC for a set period, all channels will be disconnected immediately.
  • Reset: channel faults may be reset using the RESET switch toggling the switch will clear any faults, re-enable all channels, and change all the LED lights to green