The 35-Series and 26-Series as well as most previous models of PowerLabs use the I2C connection standard to connect to ADInstruments Front-End Amplifiers and Instruments. The maximum number of I2C 'slots' available for each PowerLab model series is listed below:
- PowerLab SP-Series: 16
- PowerLab 20-Series: 8
- PowerLab 25-Series: 8
- PowerLab 26-Series: 6
- PowerLab 30-Series: 16
- PowerLab Teaching Series (15T and 26T): 6
- PowerLab 35-Series: 16
Generally, each input channel on an ADInstruments Front-End device will require the use of one I2C slot. However, a PowerLab will only be able to record from as many Front-End device channels as it has available analog inputs. For example, a PowerLab 4/35 has the required number of I2C slots to connect to an Octal Bio Amplifier; however, it can only record signals from four of the Octal Bio Amplifier's channels.
Multiple Front-End devices can be 'daisy-chained' together via multiple I2C cables to connect to a single PowerLab. However, if the number of required I2C slots for the multiple Front-Ends exceeds the number of I2C slots available, the PowerLab will assign the I2C slots to the Front-End devices in the order that they are connected to the PowerLab's I2C output connector.
For example, connecting an Octal Bio Amplifier , a Quad Bridge Amplifier , and another Octal Bio Amplifier in that order to a PowerLab 16/35 will allow you to use all eight channels of the first Octal Bio Amplifier, all four channels of the Quad Bridge Amplifier, but only the first four channels of the last Octal Bio Amplifier (See Image Below).
For further technical assistance with this or any other issue, please contact ADInstruments Technical Support by clicking HERE.