[TBB Power] BI1248-1200 | DC-DC Converter Charger

Document Title: BI124 DC-DC Converter Manual.pdf
Applies to: All Harvok caravans equipped with 120A Anderson-style towing charge system
Device Function: 12V DC-DC Converter for alternator-based towing charge
Location: Inside caravan, connected to 120A Anderson plug input


Key Features

  • Converts alternator output to suitable charging voltage for 48V battery system via built-in step-up
  • Supports up to 1200W / 100A power flow
  • Ignition-activated charging via 12-pin plug (Pin #12)
  • Internal DIP switch configuration for smart vs standard alternators
  • Includes overvoltage, undervoltage, and over-temp protection

Wiring Notes

  • Use 25mm² cable for safe high-current transmission from vehicle to caravan
  • Ignition signal must be wired correctly from tow vehicle to enable activation

DIP Switch Configuration (Standard Setup)

SwitchPositionDescription
#1ONEnable charging
#2OFFDefault
#3ON/OFFON for Smart Alternator, OFF for Standard
#4OFFDefault
#5OFFDefault
#6OFFDefault

Troubleshooting Indicators

  • Unit will fail to start if ignition wire is not active
  • Clicking on/off indicates unstable alternator supply or incorrect DIP settings
  • For stable operation, ensure alternator maintains sufficient voltage even under load
Download Manual