A digital indicator does not have to mean buying digital load cells. Fit a conversion board to a conventional analog cell and the indicator sees a digital cell. This is the usual route when a bridge already has good analog cells, or when only one has to be replaced.
What this setup needs
Analog cell + digital board = digital load cell, as far as the indicator is concerned.
Board input — from the analog cell
One side of the board takes the four wires of an ordinary load cell:
| Board terminal | Load cell signal |
| +E | Excitation supply |
| −E | GND |
| +IN | Signal + (Sig+) |
| −IN | Signal − (Sig−) |
Board output — RS-485 to the indicator
The other side is an RS-485 link into the DS1 digital indicator:
| Board terminal | Indicator side |
| +E | +12 V |
| −E | GND |
| −T and −R | B |
| +T and +R | A |
Supply for the digital board is 12 V DC. Check this before powering up — the board does not survive the wrong voltage.
Boards by protocol
The board has to match the protocol the indicator expects. Two are common in the field:
Use a prepared junction box
A moulded junction box with the terminals already wired makes installation considerably faster and leaves fewer opportunities for a wiring mistake inside a weighbridge pit.
Watch: MK-Di01 with an analog cell through a board
Where these systems fail
Nearly every fault on a digital indicator system is a lost communication link, and there are two usual causes:
- A broken signal conductor
- A failed digital board, which drops the cell off the bus
Installation note
KALA Technical Notes
Converting an existing analog bridge is often cheaper than replacing every cell, but only if the board protocol matches the indicator. Tell us the indicator model and the load cells already installed, and we will confirm which board suits them.
● Conversion boards, digital indicators and prepared junction boxes.