Gravity Analog Signal Isolator Optocoupler

The Gravity analog signal isolator from DFRobot galvanically isolates an analog sensor from the microcontroller. This is needed, for example, when a pH sensor and a conductivity sensor measure in the same container and would otherwise interfere with each other. The module supplies the sensor via its own isolated 5 V supply and passes the signal on at a ratio of 1:1, the code on the microcontroller stays the same. The connectors fit the analog 3-pin Gravity sensors from DFRobot.

Recommended Accessories:

• Gravity 3pin Analog PH2.0 to Dupont Male Cable 30cm 10pcs
• Gravity IO Expansion Shield for Arduino V7.1
• Gravity Analog pH Sensor Meter Kit V2
• Gravity Analog TDS Sensor Meter for Water Purity

Features:

• Galvanic isolation between sensor and microcontroller
• Own isolated 5 V supply for the sensor on the SEN side, up to 170 mA
• Analog signal 0 V to 5 V at a ratio of 1:1, deviation typically below ±20 mV
• SEN side to the sensor, MCU side to the microcontroller
• The MCU side needs 5.0 V ± 0.1 V, the more accurate the supply, the more accurate the signal
• The module draws a relatively high current, DFRobot recommends an external supply for the Arduino
• GND of the MCU and SEN sides are separate and must not be connected
• The module gets warm during operation, which according to DFRobot is normal

Application Examples:

• Water quality with several sensors in the same container, for example pH, conductivity and TDS
• Aquariums and hydroponics
• Analog measurements disturbed via a common ground

Documentation:

• Wiki DFRobot DFR0504
• Schematic (PDF)
• Guide with conductivity sensor (DFRobot)

Technical Data:

• Manufacturer: DFRobot
• Manufacturer SKU: DFR0504
• Operating voltage: 5.0 V
• Supply MCU side: 5.0 V ± 0.1 V
• Analog output MCU side: 0 V to 5.0 V
• Supply for the sensor, SEN side: 5.0 V ± 0.2 V, max. 170 mA
• Analog input SEN side: 0 V to 5.0 V
• Deviation between the sides: typically below ±20 mV
• Response time: typically 4 s
• No-load current: 75 mA
• Connector: PH2.0-3P
• Dimensions: 42 × 32 × 12 mm
• Weight: 17 g

Scope of Delivery:

• 1× Gravity analog signal isolator
• 2× Cable PH2.0-3P, plug on both ends