23 Verification and Troubleshooting Verification & Troubleshooting

23 Verification and Troubleshooting Verification & Troubleshooting
23
23
Verification & Troubleshooting
Verification and Troubleshooting
If you have used the guidelines shown previously in Step 3, Starting the Network,
you are now ready to verify that the unit is operating properly. Check the D2–DCM
indicators to verify the D2–DCM is operating correctly. The following diagram shows
the proper indicator conditions.
Note: Online/Offline switch has been removed from the drawing for clarity.
Module Power:
ON
NK: ON if a NAK
is either sent or
received
TO: ON if a
timeout has
occurred in the
D2–DCM
MA:
ON if master
OFF if slave
OK: ON if self test is OK
EQ: Send/Receive Enquiry
FLASHING*
HD: Send/Receive Header
FLASHING*
DA: Send/Receive
Data Packet:
FLASHING*
* During Communication only
Data Communications Module, 2nd Edition, 2/03
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Verification & Troubleshooting
Troubleshooting
Quick Steps
If the D2–DCM does not seem to be working correctly, check the following items.
These items represent the problems found most often.
1. Cable and connections. Incorrectly wired cables and loose connectors
cause the majority of problems. Verify you’ve selected the proper cable
configuration and check the cable making sure it is wired correctly.
2. Dipswitch settings. Make sure you’ve set the D2–DCM to match the
communication parameters required by the master station (D2–DCM,
operator interface or host computer).
3. Incorrect protocol. Make sure your operator interface or personal computer
software can use the DirectNET, Hostlink, CCM2, or MODBUS RTU
protocol.
4. Communications program. Check the communications program for errors.
Consult the DirectNET Manual or the manuals that came with your host
computer software or operator interface for details.
NOTE: If you need more in depth troubleshooting, see the chart on the next page. It
provides several different indicator patterns that may help identify your exact
problem.
Data Communications Module, 2nd Edition, 2/03
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Verification & Troubleshooting
Troubleshooting Chart The following chart identifies the indicator status, possible cause, and corrective
off
on
flash
action for a wide variety of commonly found problems.
Master Station Indicators
Slave Station Indicators
Power or OK is off.
Possible Cause
1.Master PLC power is disconnected
2.D2–DCM is defective
Power and OK are on.
Master indicator is off.
1.Switch setting on master station is
incorrect
Power, OK, and MA are on.
1.The master station CPU not in RUN.
EQ does not come on when
the communications program is
executed.
2.Online/Offline switch is set to OFF.
Power, OK, and MA are on.
1.COM Timeout is disabled.
1.
2.
3.
3.Communications program is not
correct.
EQ stays on, but NK, TO, or
HD indicators do not come on
at all.
4.
2.RTS and CTS signals are not
looped back on the D2–DCM end
of the cable.
Power, OK, and MA are on.
1.RLL Communications program is
incorrect.
EQ stays on, and TO flashes.
5.
2.Settings are different.
Only PW and OK
OR
EQ flashes.
3.Cable problem.
Power, OK, and MA are on.
1.Settings are different.
EQ stays on, and NK flashes.
6.
2.Cable problem or Slave is offline.
EQ & NK come on
OR
EQ and HD
flash.
Power, OK, and MA are on.
1.Settings are different.
EQ and HD come on. TO
flashes.
7.
EQ & HD come on
Power, OK, and MA are on.
1.RLL Communications program is
incorrect.
EQ and HD come on. EQ goes
off. HD stays on, and NK
flashes or stays on.
8.
2.Settings are different.
EQ & HD come on
Power, OK, and MA are on.
DT is on, but NK flashes on
occasion.
THEN
EQ goes off, HD
and NK are on
1.Electrical noise.
9.
Data Communications Module, 2nd Edition, 2/03
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Verification & Troubleshooting
Corrective Action
Switch Settings & Port Pinouts
Switch Settings
1.Check the master PLC source power.
1.
2.Replace the D2–DCM.
Switch Positions
Protocol
1
DirectNET Slave
OFF
DirectNET Master
OFF
DirectNET Peer
ON
MODBUS RTU
ON
SW3
2.
1.Disconnect the master station PLC power,
remove the D2–DCM and check positions
1 & 2 on SW3.
COM Timeout Enable
Hexadecimal Mode
1.Place the CPU in RUN mode.
3.
1.Disconnect the PLC power, remove the
D2–DCM and check position 3 on SW3.
2.Remove master station connector,
ensure that RTS & CTS are connected
according to the cable diagram.
5.
Network
Protocol
COM Timeout Disable
ASCII Mode
OFF ON
2.Set the switch to the ON position.
3.Make sure the RX or WX instruction is
being executed. Check the address,
slot number, and amount and type of
data used in the RX/WX instructions.
4.
1
2
3
4
SW5
1
2
3
4
5
6
7
8
NO Parity
Set to OFF
1.Check the address, slot number, and
amount and type of data used in the
RX/WX instructions.
Baud Rate
ODD Parity
Self Test
Switch Positions
Baud
1
2
3
300 ON OFF OFF
600 OFF ON OFF
1200 ON ON OFF
2400 OFF OFF ON
4800 ON OFF ON
9600 OFF ON ON
19200 ON ON ON
38400 OFF OFF OFF
Delay Time
OFF ON
2.Make sure baud rate, parity, and mode
(HEX/ASCII) match between the
master and slave.
3.Verify that the cable is wired properly.
6.
1.Make sure baud rate, parity, and mode
(HEX/ASCII) match between the
master and slave.
2.Verify that the cable is wired properly.
Also, make sure slave is online.
7.
1.Make sure baud rate, parity, and mode
(HEX/ASCII) match between the
master and slave.
Port Pinouts
RS232C
RS232 TXD
RS232 RXD
RS232 RTS
RS232 CTS
+5V
0V
1
14
2
15
1.Make sure the system has good earth
grounds. Only one end of the cable
shield must be grounded.
2.If you’re using RS232C, try RS422.
Data Communications Module, 2nd Edition, 2/03
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3
3
16
16
4
4
17
17
5
5
18
6
19
7
20
22
9.
14
2
21
2.Make sure baud rate, parity, and mode
(HEX/ASCII) match between the
master and slave.
RS422*
1
9
1.Check the amount and type of data
being transferred. (Byte count may be
set to 1 or an odd number for a data
type that requires 2 bytes.)
Switch Positions
Time*
6
7
8
0 OFF OFF OFF
2 ON OFF OFF
5 OFF ON OFF
10 ON ON OFF
20 OFF OFF ON
50 ON OFF ON
100 OFF ON ON
500 ON ON ON
*Delay time in milliseconds
8
8.
2
OFF
ON
OFF
ON
10
23
11
24
12
25
13
+5V
0V
RS422 RTS+
RS422 RTS–
RS422 RTS+
RS422 RTS–
RS422 CTS+
RS422 CTS–
RS422 TXD+
RS422 TXD–
RS422 RXD–
RS422 RXD+
18
6
19
7
20
8
21
9
22
10
23
11
24
12
25
13
RS422 TXD+
RS422 TXD–
RS422 RXD–
RS422 RXD+
* RS422 pins are internally connected
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