Shear pin fault, Configuration, Application example – Rockwell Automation 20B PowerFlex 70, PowerFlex 700 Reference Manual User Manual
Page 157
Shear Pin Fault
Rockwell Automation Publication PFLEX-RM001H-EN-P - June 2013
157
Shear Pin
Fault
This feature allows the user to select programming that will fault the drive if the
drive output current exceeds the programmed current limit. As a default,
exceeding the set current limit is not a fault condition. However, if the user wants
to stop the process in the event of excess current, the Shear Pin feature can be
activated. By programming the drive current limit value and enabling the
electronic shear pin, current to the motor is limited, and if excess current is
demanded by the motor, the drive will fault.
Configuration
The Shear Pin Fault is activated by setting Bit 4 of [Fault Config 1] to “1.”
The programmable current limit [Current Lmt Sel] should also set to identify
the source of the current limit value. If “Cur Lim Val” is selected, then [Current
Lmt Val] should be set to the required limit value.
A separate fault (Shear Pin Fault, F63) dedicated to the Shear Pin feature, will be
generated if the function is activated.
Application Example
In some applications, mechanical hardware can be damaged if the motor is
allowed to develop excess torque. If a mechanical jam should occur, shutting
down the system may be the only way to prevent damage. For example, a chain
conveyor may be able to “hook” itself, causing a jam on the conveyor. Excess
torque from the motor could cause chain or other mechanical damage.
By programming the Shear Pin feature, the user can cause the drive to fault,
stopping the excess torque before mechanical damage occurs.
238 [Fault Config 1]
Enables/disables annunciation of the listed faults.
D
YNAMIC CONT
R
O
L
147 [Current Lmt Sel]
Selects the source for the adjustment of
current limit (i.e. parameter, analog input,
etc.).
Default:
Options:
0
0
1
2
“Cur Lim Val”
“Cur Lim Val”
“Analog In 1”
“Analog In 2”
146
149
1
x
1
0
0
0
1
0
0
0
x
0
0
x
x
x
10
0
1
2
3
4
5
6
7
8
9
11
12
13
14
15
1
=Enabled
0
=Disabled
x =Reserved
Bit #
Factory Default Bit Values
Po
wer Loss
UnderV
olta
ge
Motor OverLd
Shear Pin
A
utRst T
ries
Decel Inhibt
Motor Therm
*
In PhaseLoss *
Load Loss *
ShearPNo Acc *
Out PhaseLoss *
* Vector firmware 3.001 & later