5–4
How Communication Takes Place and I/O Image Table Mapping with the DeviceNet Adapter
Publication 1794-6.5.7 – April 1997
00
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
Dec. Bit
00
01
02
03
04
05
06
07
10
11
12
13
14
15
16
17
Octal Bit
Read Word 7
Channel 5 Input Data
Read Word 8
Channel 6 Input Data
Read Word 9
Channel 7 Input Data
Read Word 10
Overrange Bits
Underrange Bits
Read Word 11
0
0
0
0
0
Bad
Cal
Cal
Done
Cal
Range
0
Diagnostics
Pwr
Up
Bad
Structure
CJC
over
CJC
Under
Thermocouple/mV Input Module (1794-IT8) Write
Dec. Bit
15
14
13
12
11
10
09
08
07
06
05
04
03
02
01
00
Octal Bit
17
16
15
14
13
12
11
10
07
06
05
04
03
02
01
00
Write Word 1
8-Bit Calibration Mask
Cal
Clk
Cal hi
Cal lo
Filter Cutoff
FDF
Data Type
Write Word 2
Thermocouple 3 Type
Thermocouple 2 Type
Thermocouple 1 Type
Thermocouple 0 Type
Write Word 3
Thermocouple 7 Type
Thermocouple 6 Type
Thermocouple 5 Type
Thermocouple 4 Type
Where:
FDF = fixed digital filter bit
Word/Bit Descriptions for the 1794-IT8 Thermocouple/mV
Input Module
Word
Decimal Bit
(Octal Bit)
Description
Read Word 1
00–15 (00–17)
Reserved
Read Word 2
00–15 (00–17)
Channel 0 Input data
Read Word 3
00–15 (00–17)
Channel 1 Input data
Read Word 4
00–15 (00–17)
Channel 2 Input data
Read Word 5
00–15 (00–17)
Channel 3 Input data
Read Word 6
00–15 (00–17)
Channel 4 Input data
Read Word 7
00–15 (00–17)
Channel 5 Input data
Read Word 8
00–15 (00–17)
Channel 6 Input data
Read Word 9
00–15 (00–17)
Channel 7 Input data
Read Word 10
00–07 (00–07)
Underrange bits – these bits are set if the input signal is below the input channel’s minimum range.
08–15 (10–17)
Overrange bits – these bits are set if 1), the input signal is above the input channel’s maximum range,
or 2), an open detector is detected.
Read Word 11
00 (00)
Cold Junction sensor underrange bit. – this bit is set if the cold junction temperature is below 0
o
C.
01 (01)
Cold Junction sensor overrange bit. – this bit is set if the cold junction temperature is above 70
o
C.
02 (02)
Bad Structure – this bit is set if there is an invalid thermocouple type selected.
Содержание 1794-IT8
Страница 1: ...User Manual Thermocouple Millivolt Input Module Cat No 1794 IT8 Allen Bradley ...
Страница 4: ...soc ii Summary of Changes Publication 1794 6 5 7 April 1997 ...
Страница 8: ...Table of Contents iv Publication 1794 6 5 7 ...
Страница 14: ...Overview of FLEX I O and your Thermocouple mV Module 1 4 Publication 1794 6 5 7 ...
Страница 64: ...Specifications A 10 Publication 1794 6 5 7 March 1997 ...