Rack 3: ai, Table 7 rack 2: state output descriptions, Table 8 rack 3: channel field voltage – Rockwell Automation T8402 Trusted Dual 24V dc Digital Input Module - 60 Channel User Manual
Page 18: Trusted, Module t8402

Trusted
TM
Module T8402
Issue 13 April 10
PD-T8402
18
Value
Description
7
Unknown
6
Over-range
5
Short circuit
4
Closed contact
3
Indeterminate
2
Open contact
1
Open circuit
0
Under-range
Table 7 Rack 2: STATE output descriptions
The input channel has a value 7 (Unknown) when:
1. The input channel cannot be correctly measured by two or more slices of the TMR input
module.
2. The TMR Processor detects a 1-oo-2D channel discrepancy between the appropriate slices
of the Dual input module.
3. The module is simulated (not installed or the TMR Processor cannot communicate with
1-oo-2D slices of the module).
3.2.3. Rack 3: AI
The AI board returns the field loop voltage at the input.
Channel
Description
1
Field input channel 1 voltage
2
Field input channel 2 voltage
60
Field input channel 60 voltage
Table 8 Rack 3: Channel Field Voltage
The voltage is the median value taken from the triplicated module. The voltage level is reported as an
integer, with the units being
1
/
512
V. This may be used directly, scaled arithmetically or scaled using the
IEC1131 TOOLSET conversion tables.
When used directly the value may be considered as a signed, fixed-point binary value, i.e.:
Bit
15
14 13 12 11 10 9
8
7
6
5
4
3
2
1
0
Sign
Integer
Fractional
Table 9 Rack 3: Channel Field Voltage bit definitions
To scale the value arithmetically, simply divide the input value by 512 to return the voltage as either a
REAL or INTEGER as required.