Rockwell Automation 61C350 2-In/2-Out 0-10 Volt Analog Rail Module User Manual

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2Ć4

DAC

IĆOUT

RFB

+15V

+VĆOUT

-VĆCOMMON

10K

Figure 2.2 Ć Typical Output Circuit

to A/D

converter

VĆIN

VĆOUT

90K

Figure 2.3 Ć Typical Input Circuit

The Analog Rail module is factory calibrated and requires no

offset/gain adjustment. All four analog I/Ochannels are referenced

to the same common. This common is isolated from both the

external power supply and the I/Oport connection.
The module incorporates extensive diagnostics. In Rail mode, check

bits are monitored for accuracy on every transfer of data between

the host and the module. In Local Head mode, parity bits are

monitored for accuracy on every transfer of data. A Rail fault LED on

the processor, Remote Head, or Local Head will be illuminated if the

check bits or parity bits are wrong and all transmission will stop after

n retries, where n is a value determined by the host's software

(average n = 4 for AutoMax; AutoMate n = 2).
In the event of a rail fault, all outputs will be set to 0. The COM OK"

LED on the module will go off. If any power required by the module,

i.e., the +5 Volts from the I/Oport required for communication, the

external power supply, or the power required by the Analog I/O

section, is not within specified limits, all outputs will be set to 0 and

the PWR OK" LED will go off.