Rockwell Automation 1771-QC , D17716.5.25 SER/B SERVO POS - Manual (Page 223)

Troubleshooting
Chapter 10
10Ć11
Flowchart Notes
The following notes are referenced by numbers of the flowchart of
Figure 10.5.
1. Refer to section titled “Monitoring 1771-M3 Controller Indicators,”
in this chapter.
2.
CAUTION: To guard against damage to equipment, power down the
system before removing or installing any module.
3. Refer to Figure 6.1
4. Refer to section titled “Monitoring 1771-ES Expander Indicators,” in
this chapter.
5. On the left 1771-ES expander wiring arm, measure the voltage at
terminal 1 with respect to terminal 12. It should equal the input
supply voltage. If it doesn’t, check the power supply. If it does,
measure the voltage at terminal 11. This voltage should be zero. If
it’s not zero, check for a closed circuit between terminals 11 and 12.
(Refer to Figure 5.1 and section titled “Discrete Inputs”).
6. The module address programmed in the block transfer instruction
must be the address of the 1771-M3 controller. The rack number in
the module address must match the setting of the I/O chassis
switches.
7. Refer to the sample program of section titled “Programming
Example” in chapter 8 for examples of rungs that perform this
function.
8. The second word of the status block specifies the starting address of
the block to transfer to the 1771-M3 controller. Be sure that this
address specifies the actual starting address of a parameter, moveset,
or command block. If it does not, check the corresponding address
pointer in the parameter block and make necessary corrections. Also
check that the parameter block I.D. bits are correctly programmed
(bits 10 thru 17, word 1). If they are not, the 1771-M3 controller does
not accept the parameter block.
9. Refer to Table 7.D. Note that in some cases, ladder diagram
execution timing can cause illegal bit combinations to be on