LPG Dial Digitizer

“The same analogue dial, now read every minute.”

LPG tanks at Pertamina's filling station in Balikpapan used old analogue dials to show their level. Operators recorded the readings by hand twice a day, photographing the dial and typing in the number. The time gaps and manual recording left room for fraud.

Pertamina wanted to curb that fraud without replacing the dials already installed. Hardtmann researched a way to read the needle position directly and send the result for remote monitoring.

How it works

• First version: an infrared sensor read the needle position, taking advantage of the dial's black needle.
• Second version: switched to a magnetic sensor to read the needle position.
• Each tank was fitted with three sensors. The pilot ran on two tanks on site.

Results

Tank levels are read and recorded every minute instead of twice a day. The data no longer depends on operator notes, so the numbers cannot be manipulated.

Challenges

• Reading analogue dials without replacing the installed equipment
• Outdoor installation in a Zone 0 area with explosive gas risk
• Fraud attempts in the field by hitting and damaging the devices