Product Manual 1130 - pH/ORP Adapter
Phidgets 1130 - Product Manual For Board Revision 0 © Phidgets Inc.
Contents 4 Product Features 4 Connections 4 Type of Measurement 5 Getting Started 5 Checking the Contents 5 Connecting all the pieces 5 Testing Using Windows 2000/XP/Vista 7 Testing Using Mac OS X 7 Programming a Phidget 7 Code Samples 7 Coding for your Sensor 8 Technical Information 8 Measuring the pH 8 Measuring Oxidation/Reduction Potential (ORP) 8 Words of Caution 8 Choosing Electrodes 8 Other Interfacing Alternatives 9 Analog Input Cable Connectors 9 Mechanical Drawing 10
Product Features • Interfaces to a glass electrode through a common BNC connection • Measures the pH or ORP level of a substance Connections Designed to connect to a: • 1018 - PhidgetInterfaceKit 8/8/8 • 1019 - PhidgetInterfaceKit 8/8/8 w/6 Port Hub • 1070 - PhidgetSBC • 1202 - PhidgetTextLCD Type of Measurement The sensor uses non-ratiometric measurement.
Getting Started Checking the Contents You should have received: • An pH/ORP Adapter Board In order to test your new Phidget you will also need: • A PhidgetInterfaceKit 8/8/8 • A Sensor Cable • A USB Cable • A pH or ORP electrode Connecting all the pieces 1. 2. Connect the pH/ORP Adapter Board to the Analog Input #6 on the PhidgetInterfaceKit 8/8/8 board using the sensor cable. In this example, we are using a pH electrode. Connect the electrode to the adapter board using the BNC connector. 3.
Double Click on the icon to activate the Phidget Control Panel and make sure that the Phidget InterfaceKit 8/8/8 is properly attached to your PC. 1. Double Click on Phidget InterfaceKit 8/8/8 in the Phidget Control Panel to bring up InterfaceKit-full and check that the box labelled Attached contains the word True. 2. Make sure that the Ratiometric box is NOT Ticked. 3. View the unconverted pH value inside the Analog In boxes. At a pH level of 7 or with a neutral ORP, the SensorValue will be 500. 4.
Testing Using Mac OS X • Click on System Preferences >> Phidgets (under Other) to activate the Preference Pane • Make sure that the Phidget InterfaceKit 8/8/8 is properly attached. • Double Click on Phidget InterfaceKit 8/8/8 in the Phidget Preference Pane to bring up the InterfaceKit-Full example. This example will function in a similar way as the Windows version, but note that it does not include an Advanced Sensor Display.
Technical Information Measuring the pH To determine the pH of a solution, make sure the DIP switch on the board is flipped to the pH side. Given the SensorValue from the Phidget InterfaceKit, the following formula can be applied: pH = 0.0178 * SensorValue - 1.889 This formula assumes that the solution is at 25 degrees Celsius. Depending on the temperature of the solution and on the actual pH level, the SensorValue can change dramatically.
Analog Input Cable Connectors Each Analog Input uses a 3-pin, 0.100 inch pitch locking connector. Pictured here is a plug with the connections labeled. The connectors are commonly available - refer to the Table below for manufacturer part numbers.
Device Specifications Characteristic Value Current Consumption 3.0 mA Input Impedance >1 TeraOhm Input Voltage 4.5 V to 5.25 V pH Specifications Input Range -400 mV to +400 mV Input Resolution 1 pH / 54.4 SensorValue Min/Max Error ±0.09 pH Typical error ±0.
