Diesel Tank Management - Power Supply and Relay Setup

The IoT Pro Diesel Tank Management Module is supplied by default to work with a 230VAC power supply input and a 230VAC diesel fuel pump. The guide below walks you through modifying the internal power supply and relay wiring to configure the system for 12VDC, or 24VDC fuel pumps. The overall system supply voltage must match the pump supply voltage (e.g., maintain a 12VDC system supply for a 12VDC pump, and a 24VDC system supply for a 24VDC pump).

Before opening the enclosure or modifying any wiring, ensure the main system power is off and take all standard electrical safety precautions.

Removing Existing Power Supplies & Relay

  1. Power Down: Verify the system power is off, then open the enclosure door

  2. Remove AC/12VDC Power Supply: Remove the unit (labeled PSR01512) and disconnect its 12V domain wires from the middle DIN terminal blocks (positions 1-2, 3-4)

  3. Remove AC/5VDC Power Supply: Remove the unit (labeled PSR01505) and disconnect its 5V domain wires from the middle DIN terminal blocks (positions 5 and 6)

  4. Remove Relay: Unclip and remove the existing 12VDC (for 230VAC) DIN-mounted relay


Power Supply Configuration

Use the table below to determine the correct DC/DC converter required for your system voltage and barcode scanner setup:

Pump/System Supply

Wired Barcode Scanner

Wireless Barcode Scanner

12VDC

9-36VDC/5VDC (P/N: DDR-15G-5)

Wire directly to main 12VDC supply (low power draw)

24VDC

9-36VDC/5VDC (P/N: DDR-15G-5)

9-36VDC/12VDC (P/N: DDR-15G-12)

For detailed steps on installing the wireless barcode scanner, see Diesel Tank Management - Wireless Barcode Scanner Setup

Installation Steps (12VDC)

  1. Bridge the main 12VDC input directly to the middle DIN terminal blocks

  2. If using a wired barcode scanner: Connect the 5V output from the DC/DC converter (P/N: DDR-15G-5) to the 5V DIN terminal blocks

Installation Steps (24VDC)

  1. Bridge the main 24VDC input directly to the middle DIN terminal blocks (positions 1-2, 3-4)

  2. If using a wired barcode scanner: Connect the 5V output from the DC/DC converter (P/N: DDR-15G-5) to the 5V DIN terminal blocks (positions 5 and 6)

  3. If using a wireless barcode scanner: Provide 12VDC via the DC/DC converter (P/N: DDR-15G-12). Then use the previously 5V DIN terminal blocks (positions 5 and 6) to create a 12V voltage domain.


Component & Wiring Modifications

Wiring

  • A 2-core 4mm2 wire should replace the 3-core 2.5mm2 wire entering both supply and pump output glands. A 3-core 4mm2 with the earth wire cut can also be used

Buzzer

  • Change the buzzer on the front panel to a 24VDC one (P/N: 3916M-24VDC) if opting for a 24VDC supply

Relay

  • Change the DIN mounted relay to an automotive 12VDC (P/N: LD-12P or similar) or 24VDC (P/N: FRC2C-DC24 or similar) one

  • Spade connectors with appropriate 4mm2 wiring is recommended to be used here to bridge the supply input properly

  • Tie the relay to DIN rail with a cable tie