Rockwell Automation 61C542 Voltage Input module - Manual (Page 24)

4Ć6
4.1.5 Low Low Alarm Status Register (Register 19)
Register 19 indicates the current status of each configured channel's
Low Low alarm. See figure 4.5. A bit is set in this register whenever a
channel's input value is less than the configured Low Low alarm limit.
The bit is reset when the input value returns to a level above the
configured limit.
When two channels are configured as a differential pair, only the bit
representing the first channel (evenĆnumber) will be updated. The
second channel's status bit will remain at zero.
Register 19
Bits 0Ć15
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
Bit 5 = Channel 5
Bit 6 = Channel 6
Bit 7 = Channel 7
Bit 8 = Channel 8
Bit 9 = Channel 9
Bit 10 = Channel 10
Bit 11 = Channel 11
Bit 12 = Channel 12
Bit 13 = Channel 13
Bit 14 = Channel 14
Bit 15 = Channel 15
Bit 0 = Channel 0
Bit 1 = Channel 1
Bit 2 = Channel 2
Bit 3 = Channel 3
Bit 4 = Channel 4
R R R R R R R R R R R R R R R R
Figure 4.5 Ć Low Low Alarm Status Register
4.1.6 Out of Range Status Register (Register 20)
Register 20 indicates the current status of each configured channel's
Out of Range alarm. See figure 4.6. A bit is set in this register
whenever a channel's A/D input value is outside of the range of
-10.5 volts to 10.5 volts (bipolar inputs) or -0.5 volts to 10.5 volts
(unipolar inputs).
The bits in this register are not latched automatically. If you want a bit
to be latched the first time a value goes out of range, you must latch
it through the application program.
When two channels are configured as a differential pair, only the bit
representing the first channel (evenĆnumber) will be updated. The
second channel's status bit will remain at zero.
If an input is identified as being out of range, the most probable
cause is that a wire between the transmitter and the module has
either not been properly connected or has been broken.
Bits 0Ć15
Register 20
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
Bit 5 = Channel 5
Bit 6 = Channel 6
Bit 7 = Channel 7
Bit 8 = Channel 8
Bit 9 = Channel 9
Bit 10 = Channel 10
Bit 11 = Channel 11
Bit 12 = Channel 12
Bit 13 = Channel 13
Bit 14 = Channel 14
Bit 15 = Channel 15
Bit 0 = Channel 0
Bit 1 = Channel 1
Bit 2 = Channel 2
Bit 3 = Channel 3
Bit 4 = Channel 4
R R R R R R R R R R R R R R R R
Figure 4.6 Ć Out of Range Status Register