Bar100 Pressure Sensor Documentation


The Bar100 is a high pressure, underwater depth and temperature sensor that comes in a Blue Robotics penetrator form factor, making it easy to install on a waterproof enclosure.

Quick Start

  1. Download KellerLD Arduino Library.
  2. Install software such as the Example Code to your microcontroller.
  3. Connect the DF13 or bare wires to the appropriate microcontroller pins, using a logic level converter if your board has 5v logic:
    • Green: SCL (3.3v logic)
    • White: SDA (3.3v logic)
    • Red: +2.5-5.5v
    • Black: Ground



Bar100 Schematic.pdf

Specification Table

For further information please see the Keller 7LD Data Sheet.

Item Condition Value
Supply Voltage 2.5-5.5 volts
I2C Logic Voltage (SDA and SCL) 1.8 - 3.6 volts
Peak Current 1.5 mA
Item Condition Value
Maximum Mechanical Pressure 350 bar
Operating Pressure 0-100 bar [up to 3344 ft (1019 m) in freshwater]
Absolute Accuracy (0-50°C) From 0-100 bar +/- 500 mbar (5.1 m in freshwater)
Resolution From 0-100 bar 3 mbar (3 cm in freshwater)
Item Condition Value
Operating Temperature -40 to +110°C
Absolute Accuracy From 0-100 bar at 0-50°C +/- 2°C
Overall Length 41 mm  
Thread Size M10x1.5 20 mm threaded  
Recommended Through Hole Size 10-11 mm  
Wrench Flats 16 mm  

DF13 Pinout

1 Δ Red - Positive (3.3-5.5V)
2 Green - I2C Clock (SCL)
3 White - I2C Data (SDA)
4 Black - Ground

Mating Connector: Hirose 4-pos DF13 on Digi-Key

2D Drawing

3D Model

All 3D models are provided in zip archives containing the follow file types:

  • SolidWorks Part (.sldprt)
  • IGES (.igs)
  • STEP (.step)
  • STL (.stl)
Bar 100 Pressure Sensor    
Bar100 Pressure Sensor  
Bar100 Penetrator Nut  


Step 1: Lubricating the O-ring

Use a small amount of silicone grease on the O-ring for lubrication and place it in the groove of the Bar100 Pressure Sensor.

Step 2: Installation

Install the Bar100 Pressure Sensor into an endcap and tighten by hand or with a wrench.

Example Code


This example uses the BlueRobotics KellerLD Library with the connected sensor. The example reads the sensor and prints the resulting values to the serial terminal.

Please remember to use a logic level converter, such as this one, to convert Arduino 5v levels to 3.3v!

If you’ve never used Arduino before, we suggest checking out some tutorials!

#include <Wire.h>
#include "KellerLD.h"

KellerLD sensor;

void setup() {

  sensor.setFluidDensity(997); // kg/m^3 (freshwater, 1029 for seawater)

void loop() {;

  Serial.print("Pressure: "); 
  Serial.println(" mbar");
  Serial.print("Temperature: "); 
  Serial.println(" deg C");
  Serial.print("Depth: "); 
  Serial.println(" m");
  Serial.print("Altitude: "); 
  Serial.println(" m above mean sea level");



This example uses the BlueRobotics KellerLD Python Library with the sensor connected to a Raspberry Pi. The Raspberry Pi uses 3.3v logic levels on the I2C pins, so a logic level shifter is not required.

from kellerLD import KellerLD
import time

sensor = KellerLD()

if not sensor.init():
  print "Failed to initialize Keller LD sensor!"

print "Testing Keller LD series pressure sensor"
print "Press Ctrl + C to quit"

while True:
    print("pressure: %7.4f bar\ttemperature: %0.2f C") % (sensor.pressure(), sensor.temperature())
  except Exception as e:
    print e