121
SCADA-Modbus
®
System Guidelines
950 SCADA-Modbus “No-Response” Troubleshooting Flow Chart (3 of 5)
Continued from sheet 2
Swap the RX and TX
lines on the serial cable
connected to the
950.
Does the
950 meter communicate
correctly with the
Software ?
Call our
tech support
at 800 635 1230
or
Outside the U.S.& Canada,
call +1 970 669 3050
Yes
Are
the correct
number of registers being
requested for the data
type being
returned ?
Yes
To ensure the integrity of the data being returned, the 950 checks to
make sure the number of registers being requested coincides with the
data type being returned. If there are inconsistencies the meter will
ignore the polling message. For example, Floating point data requires
2 registers per value. Enumerated and Integer data requires 1 register
per value. Long integers require two registers per value. The meter
would ignore a request for just one floating point value if the number of
registers requested was only one instead of two.
Continued on sheet 4
Does the
Master device use
hardware or software
handshaking ?
Disable the handshaking in
the Master device and / or
jumper out the
handshaking terminals in
the RS232 cable
Yes
Does the
address of the Modbus
message correspond to
the address assigned to
the 950 ?
Change the Modbus
device address of the
950 in the
"Communications
Setup" menu of the
950.
No
Yes
No
Is the
meter responding
now ?
No
Congratulations !
You’ve fixed it
Yes
No
Calculate the correct
number of registers
needed for the data types
being returned and then
change the polling
request accordingly.
No
Содержание Sigma 950
Страница 2: ......
Страница 6: ...4...
Страница 20: ...18 Introduction...
Страница 34: ...32 Basic Programming Setup...
Страница 50: ...48 Sensor Installation...
Страница 82: ...80 Maintenance...
Страница 83: ...81 Appendix A Program Flow Charts Figure 22 Overview of Basic Program Menus...
Страница 84: ...82 Program Flow Charts Figure 23 Setup Flow Chart...
Страница 85: ...83 Program Flow Charts Figure 24 Options Flow Chart...
Страница 86: ...84 Program Flow Charts Figure 25 Alarms Menus Flow Chart...
Страница 87: ...85 Program Flow Charts Figure 26 Calibration Menus Flow Chart Page 1...
Страница 88: ...86 Program Flow Charts...
Страница 102: ...100 Programming Features...
Страница 106: ...104 Primary Devices Head Measurement Locations...
Страница 126: ...124 SCADA Modbus System Guidelines...