ADInstruments FE231, Руководство пользователя

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Owner’s Guide
9
Introduction
The PowerLab controls front-ends through an expansion connector called the I 2 C (eye-
squared-sea) bus. This makes it very easy to add front-ends to the system or to transfer
them between PowerLabs. Many front-ends can be added to the system by connecting
the I
2
C sockets in a simple daisy-chain structure. The PowerLab provides control and
low-voltage power to front-ends through the I 2 C bus so, in general, no separate power
supply is required.
In addition, each front-end requires a separate connection to one or more analog input
channel(s) of the PowerLab. External signals are acquired through the PowerLab analog
inputs and amplified before being digitized by the PowerLab. The digitized signal is
transmitted to the computer using a fast USB connection. ADInstruments soft ware
applications LabChart, LabTutor, LabStation and Lt receive, display, and record the data
and your analysis to the computer’s hard disk.
Front-ends are automatically recognized by the PowerLab system. Once connected, the
features of the front-end are combined with the appropriate features of the PowerLab
(for example, range and filtering options) and are presented as a single set of soft ware
controls.
Note: The Stimulator front-ends diff er from other front-ends in two respects:
1. Since they need to produce a reasonably high voltage and current, the Stimulator
front-ends require a power supply in addition to the power provided by the I
2 C
bus.
2. As they produce voltage output for stimulation, they are connected to a positive
analog output socket of the PowerLab as a source for timing and producing
pulses.
A variety of accessory products are available with ADInstruments Front-ends, such as
transducers, signal cables and recording electrodes. Some of these are listed in the
Getting Started with Front-end Signal Conditioners booklet, supplied with your Front-
end. For more details see: http://www.adinstruments.com/ or contact your local
ADInstruments representative.
Checking the Front-end
Before connecting the front-end to anything, check it carefully for signs of physical
damage.
1. Check that there are no obvious signs of damage to the outside of the front-end
casing.
2. Check that there is no obvious sign of internal damage, such as rattling. Pick up
the front-end, tilt it gently from side to side, and listen for anything that appears
to be loose.
If you have found a problem, contact your authorized ADInstruments representative
immediately and describe the problem. Arrangements can be made to replace or repair
the front-end.