Chapter 4 Operation
- 66 -
4.5.7 Using the Zero Clamp Function
（
1
1
1
1
）
Zero
Zero
Zero
Zero Clamp
Clamp
Clamp
Clamp Function
Function
Function
Function
The zero clamp function is used for systems where the host controller does not form a position loop for
the speed reference input. When the zero clamp signal
（
/P-CON
）
is ON, a position loop is formed
inside the servodrive as soon as the input voltage of the speed reference (V-REF) drops below the
servomotor zero clamp speed. The servomotor ignores the speed reference and then quickly stops and
locks the servomotor.
The servomotor is clamped within ±1 pulse when the zero clamp function is turned ON, and will still
return to the zero clamp position even if it is forcibly rotated by external force.
(2)Parameter
(2)Parameter
(2)Parameter
(2)Parameter Setting
Setting
Setting
Setting
Parameter
Parameter
Parameter
Parameter
Meaning
Meaning
Meaning
Meaning
Pn005
H.□□A□
Control mode: Speed control(analog voltage reference)
Zero Clamp
Zero Clamp Conditions
Zero clamp is performed with Pn005=H.□□A□ when the following two conditions are satisfied:
·/P-CON is ON (low level)
·Speed reference (V-REF) drops below the setting of Pn502.
Host Controller
Host Controller
Host Controller
Host Controller
Speed Reference
Speed Reference
Speed Reference
Speed Reference
V
V
V
V----R E F
R E F
R E F
R E F
Zero Clamp
Zero Clamp
Zero Clamp
Zero Clamp
////P
P
P
P----C O N
C O N
C O N
C O N
When the
When the
When the
When the ////P
P
P
P----CON signal is turned ON
CON signal is turned ON
CON signal is turned ON
CON signal is turned ON, , , , a
a
a
a
speed reference below the Pn
speed reference below the Pn
speed reference below the Pn
speed reference below the Pn
502
502
502
502 setting is
setting is
setting is
setting is
det ect ed
det ect ed
det ect ed
det ect ed....
Stops precisely
Stops precisely
Stops precisely
Stops precisely !!!!
C N
C N
C N
C N 1
1
1
1
1
1 5
V
V
V
V----R E F
R E F
R E F
R E F
////P
P
P
P----C O N
C O N
C O N
C O N
Speed reference
Speed reference
Speed reference
Speed reference
Zero clamp
Zero clamp
Zero clamp
Zero clamp
Servodrive
Servodrive
Servodrive
Servodrive
“
V
V
V
V----R E F
R E F
R E F
R E F
”
speed reference
speed reference
speed reference
speed reference
T im e
T im e
T im e
T im e
S p eed
S p eed
S p eed
S p eed
Preset value for zero
Preset value for zero
Preset value for zero
Preset value for zero
clamping Pn
clamping Pn
clamping Pn
clamping Pn5 0 2
5 0 2
5 0 2
5 0 2
O p e n
O p e n
O p e n
O p e n
（
O F F
O F F
O F F
O F F ))))
C losed
C losed
C losed
C losed
（
O N
O N
O N
O N ))))
“
////P
P
P
P----C O N
C O N
C O N
C O N
”
input
input
input
input
Zero clamp is performed
Zero clamp is performed
Zero clamp is performed
Zero clamp is performed ....
O N
O N
O N
O N
O F F
O F F
O F F
O F F
O F F
O F F
O F F
O F F
O N
O N
O N
O N
O N
O N
O N
O N
