User Manual V 1-4.XX User guide

12-22 Troubleshooting
Understanding the Parameter
Limit Faults
If you receive a Param Limit fault (03057) or warning (03089), the
drive has limited the value of one or more parameters. When you
enter a parameter value from a programming device (such as a
Human Interface Module (HIM)), the drive checks the value against
the minimum and maximum parameter range. However, parameter
values can also change as a result of a link to that parameter. When a
parameter value is changed indirectly by a link, the drive performs
additional limit checking on several critical parameters.
For example, if you create a link between Pos Mtr Cur Lim
(parameter 72) and An In 1 Value (parameter 96), An In 1 Value could
change the value of Pos Mtr Cur Lim. If the analog input level
exceeds the range of Pos Mtr Cur Lim, the drive limits the data value
that is stored as a current limit. When this happens, a parameter limit
condition has occurred.
You can configure the drive to report a parameter limit condition as
either a fault or a warning, or to ignore the condition.
The drive performs a parameter limit check regardless of how you
configure it to report the condition.
Using the Parameter Limit Testpoints
When a parameter limit fault or warning occurs, you need to look at
two software testpoints, Test Data 2 (parameter 94) and Test Select 2
(parameter 95) to identify which parameter(s) is being limited.
If Test Data 2 is non-zero, the value indicates which parameter limit
condition has occurred. A bit position is assigned to each limit
condition. Therefore, a value of 1 corresponds to bit 0, 2 for bit 1, 4
for bit 2, and so forth. Typically, only a single parameter limit
condition will occur at a time. If multiple conditions do occur, you
need to interpret the testpoint value as a combination of more than
one bit, for example bits 0 and 1 = decimal value 1+2 = 3.
To view the testpoints:
1. Enter a value of 10503 into Test Select 2 (parameter 95).
2. Look at the value of Test Data 2 (parameter 94). If Test Data 2 is
zero, go on to step 3. If Test Data 2 is non-zero, use the following
table to determine which parameter is being limited.
To: You need to:
Report the condition as a fault Set bit 9 in Fault Select 2 (parameter 22).
Report the condition as a warning
Clear bit 9 in Fault Select 2 and set bit 9 in
Warning Select 2 (parameter 23).
Ignore the condition
Make sure that bit 9 is clear in both Fault Select 2
and Warning Select 2.
file:
Fault Setup
group:
Testpoints
If Test
Data 2 is:
Then, this
parameter:
Has been
limited to:
1 (bit 0)
Rev Speed Limit
(parameter 40)
The minimum/maximum range
2 (bit 1)
Fwd Speed Limit
(parameter 41)
The minimum/maximum range