OPTO 22 PAMUX, Руководство пользователя

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INTRODUCTION
Pamux User’s Guide
1-7
TERM1 TERMINATOR BOARD
Both ends of a Pamux bus must be terminated. At the host computer end of the bus, an adapter card
such as the AC28 includes terminator resistors. At the other end, the final Pamux brain board on the bus
must be terminated with a TERM1 or TERM2 terminator board.
Terminator boards plug directly into B5 and B6 brain boards. At a B4 station, a terminator board plugs
into the I/O mounting rack such that the component side of the terminator board faces away from the
modules.
Figure 1-7: TERM1 Terminator Board
TERM2 TERMINATOR BOARD
The TERM2 is identical to the TERM1 in size and function. The only difference between the boards is
that the TERM2 offers lower line impedance than the TERM1.
If your Pamux system uses a cable with characteristics that differ from those recommended, you may
need to terminate the bus with the TERM2 rather than the TERM1.
Figure 1-8: TERM2 Terminator Board