Mesa 7I44, Руководство пользователя

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7I44 6
OPERATION
5V POWER
The 7I44 requires ~100 mA of 5V power for operation. This power will increase
based on the number of terminated TX outputs used, and power used by external devices.
If only low power external devices are used the 7I44 can be run entirely from cable
power. (W1 UP) If more than about 400 mA of total external power is used. It is suggested
that the 7I44 be powered form an external 5V source (W1 DOWN)
RS-485 CAPABLE CHANNELS
All of the serial channels on the 7I44 have output enables and can be used for RS-
485 half duplex type applications. For 2 wire half duplex type RS-485 interfaces, the RX+
and TX+ lines and the RX- and TX- lines should be tied together at the 7I44.
INTERFACING WITH MESA SERIAL DEVICES
The 7I44 in intended as an interface to MESA’s serial I/O devices that use RS-422
communication and RJ45/CAT5 cable for the serial interface. These devices include the
7I64 Isolated I/O interface, the 8I20 3 phase drive, the 7I66 isolated I/O interface, the 7I69
TTL I/O interface, 7I70 isolated input, 7I71 isolated output, and the 7I73 pendant interface.
Straight through CAT5 or CAT6 cables can be used but CAT6 is recommended for
better signal fidelity and lower voltage drop. Make sure you are using straight through
cables. Random cables from routers etc are likely to be crossover cables which will not
work and may even damage the 7I44/remote device.