Rockwell Automation 1772-L8_LW_LWP_LX_LXP,D17726.5.8 User Manual - Manual (Page 403)

Program Troubleshooting
Chapter 26
26-4
Data table bits, excluding those in the processor work area can be accessed
by the contact histogram command. The on/off status of the bit and the
length of time the bit remained on or off (in hours, minutes and seconds) is
displayed on the Industrial Terminal. The seconds are displayed within
0.01 second (10 ms) resolution.
Two operating modes for the contact histogram shown in Table 26.B are:
Continuous: Accessed by pressing [Search] [6]. The user command
displays the histogram from that instant.
Paged: Accessed by pressing [Search] [7]. The user command displays
the histogram one page at a time and requires operator action to continue
the histogram once the screen is filled.
Table 26.B
Contact Histogram Functions
Function Key Sequence Mode Description
Continuous contact
histogram
[SEARCH][6]
(Bit Address)
[DISPLAY]
Any Provides a continuous display of the on/off history of the
addressed bit in hours, minutes and seconds.
Can obtain a hardcopy printout of contact histogram by
connecting a peripheral device to Channel C and selecting
proper baud rate before indicated key sequence.
Paged Contact histogram [SEARCH][7]
(Bit Address)
[DISPLAY]
[DISPLAY]
Any Displays 11 lines on/off history of the addressed bit in hours,
minutes and seconds.
Displays the next 11 lines of contact histogram.
Can obtain a hard copy printout of contact histogram by
connecting peripheral device to Channel C and selecting
proper baud rate.
Either [CANCEL COMMAND] To terminate.
After pressing [Search] [6] or [Search] [7], enter the bit address to be
monitored. Bit addresses larger than 5 digits do not require leading zeros
or the [Expand Addr] key. After pressing [Display] , the data of the
histogram is displayed on every other line with 5 frames of data per line.
Each frame of data contains the on/off status and the length of time in the
format shown in Figure 26.1.