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Elektronik GmbH
Page 29 of 45
POS-124-*-PDP-1121
13.02.2013
5.2.21
CTRL1 / CTRL2 (Deceleration function characteristic)
Command
Parameters
Unit
Group
CTRL1
X
CTRL2
X
x= lin|sqrt1
|sqrt2
-
STD
The deceleration characteristic is set with this parameter. In the case of positively overlapped proportional
valves the SQRT function should be used. The non-linear flow function of these valves is linearised by the
SQRT
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function.
In the case of zero lapped valves (control valves and servo valves) the LIN or SQRT1 function should be
used regardless of the application. The progressive characteristic of the SQRT1 function has better posi-
tioning accuracy but can also lead to longer positioning times in individual cases.
LIN:
Linear deceleration characteristic (gain is increased by a factor of 1).
SQRT1:
Root function for braking curve calculation. The gain is increased by a factor of 3 (in the target
position). This is the default setting.
SQRT2:
Root function for braking curve calculation. The gain is increased by a factor of 5 (in the target
position). This setting should only be used with a significantly progressive flow through the
valve.
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The SQRT function generates constant deceleration and thus reaches the target position faster. This is achieved by
increasing the gain during the deceleration process.
1 Braking function with respect to stroke and time
Stroke
V
e
lo
ci
ty
Braking stroke
D:A or D:B
CTRL = LIN
CTRL = SQRT
Time
V
e
lo
ci
ty
Deceleration time
D:A or D:B
CTRL = LIN
CTRL = SQRT
