Troubleshooting; Diagnosis; No Response To Control Signals - Danfoss VLT PROFIBUS DP MCA 101 Programming Manual

Troubleshooting

8 Troubleshooting

8.1 Diagnosis

PROFIBUS-DP provides a flexible way of performing
diagnosis of slave units, based on diagnosis messages.
During normal cyclical data exchange:
1. The slave sets a diagnosis bit, which requests the
master to send a diagnosis message during the
next scan cycle, instead of the normal data
exchange.
2. The slave answers the master with a diagnosis
message consisting of standard diagnosis
information, 6 bytes, and possibly extended,
vendor specific, diagnosis information. The
standard diagnosis messages cover a limited
range of general diagnosis possibilities, whereas
8 8
the extended diagnosis function offers detailed
messaging specific to the frequency converter.
See chapter 8.3 Warnings and Alarms for the extended
diagnosis messages for the frequency converter.
A master or a network analysing tool is able to translate
these diagnosis words into real text messages using the
GSD-file.
NOTICE
DP V1 diagnosis is supported for PROFIBUS SW version
2.X and later versions. The default setting of the
PROFIBUS option is DP V1 diagnosis.
When DP V0 diagnosis is required, change the setting
under DP slave Properties.

8.2 No Response to Control Signals

Check that:
1. The control word is valid.
When bit 10=0 in the control word, the frequency
converter does not accept the control word. The
default setting is bit 10=1. Set bit 10=1 via the
PLC.
2. Relationship between bits in the control word
and the terminal I/Os is correct.
Check the logical relationship in the frequency
converter. Set the logic to bit 3=1 and digital
input=1 to achieve a successful start.
Select the FC control mode, digital input and/or serial
communication, using 8-50 Coasting Select to 8-56 Preset
Reference Select.
48
Programming Guide
Selecting control mode for 8-50 Coasting Select,
parameter 8-51 Quick Stop Select, and 8-52 DC Brake
Select:
If [0] Digital input is selected, the terminals control the
coast and DC brake functions.
NOTICE
Coasting, Quick Stop, and DC Brake functions are active
for logic 0.
Terminal
0
0
1
1
Table 8.1 [0] Digital input
If [1] Serial communication is selected, commands are
activated only when given via serial communication.
Terminal
0
0
1
1
Table 8.2 [1] Serial communication
If [2] Logic AND is selected, activate both signals to perform
the function.
Terminal
0
0
1
1
Table 8.3 [2] Logic AND
If [3] Logic OR is selected, activation of 1 signal activates
the function.
Terminal
0
0
1
1
Table 8.4 [3] Logic OR
Danfoss A/S © Rev. 05/2014 All rights reserved.
Bit 02/03/04 Function
0 Coast/DC brake/Q-Stop
1 Coast/DC brake/Q-Stop
0 No Coast/DC brake/Q-Stop
1 No Coast/DC brake/Q-Stop
Bit 02/03/04 Function
0 Coast/DC brake/Q-Stop
1 No Coast/DC brake/Q-Stop
0 Coast/DC brake/Q-Stop
1 No Coast/DC brake/Q-Stop
Bit 02/03/04 Function
0 Coast/DC brake/Q-Stop
1 No Coast/DC brake/Q-Stop
0 No Coast/DC brake/Q-Stop
1 No Coast/DC brake/Q-Stop
Bit 02/03/04 Function
0 Coast/DC brake/Q-Stop
1 Coast/DC brake/Q-Stop
0 Coast/DC brake/Q-Stop
1 No Coast/DC brake/Q-Stop
MG37G102