7 ND90 71 en
27
5.5.4 Valve type,
VTYP
To compensate for nonlinearity of the position feedback
caused by the actuator linkage mechanism of a linear con-
trol valve, the appropriate selection must be made on the
VTYP
display.
After selecting
VTYP
on the display, press the
?
key
to enter the edit state and the
VTYP
starts to blink.
Select between four values
rot
,
LIn
,
nCG
or
FLI
using the
+
and
-
keys. The value
rot
indicates a
rotary valve and
LIn
a linear valve. Use
nCG
only for
nelesCV Globe valves to accommodate special link-
age geometry. Use
FLI
only for linear valves when
linkage geometry is needed to be corrected by valve
controller.
To conclude press the
?
key when the desired
value is shown on the display.
5.5.5 Actuator type,
ATYP
In order to optimise the control performance the device
needs to be informed about the actuator type.
After selecting
ATYP
on the display, press the
?
key
to enter the edit state and
ATYP
starts to blink.
Select between two values
2
-
A
or
1
-
A
using the
+
and
-
keys. The value
2
-
A
indicates a double acting
actuator and
1
-
A
a single acting actuator.
To conclude press the
?
key when the desired
value is shown on the display.
5.5.6 Positioner fail action,
PFA
Positioner fail action will take place in case of signal failure
or when the controller software discovers a fatal device fail-
ure. For single acting actuators set value in the spring direc-
tion. For double acting actuators see Fig. 7 and 8 for correct
settings.
Once
PFA
is displayed, press the
?
key to enter the
edit state and the
PFA
will start blinking.
You may select between two values by pressing the
+
or
-
key. The
CLO
value indicates that the valve
ought to be closed in fail action situations. The
OPE
value indicates the valve to be opened in fail action
situations.
After the desired value is displayed, press the
?
key
to conclude the operation.
5.5.7 Valve rotation direction,
ROT
The application-specific parameter
ROT
defines the rela-
tionship between position sensor rotation and valve action.
Once
ROT
is displayed press the
?
key to enter the
edit state and
ROT
starts to blink.
Now you may select between two values by pressing
the
+
or
-
key. The value
cC
indicates clockwise
rotation for closing the valve and
ccC
means coun-
terclockwise to close.
After the desired value is displayed, press the
?
key
to conclude the operation.
5.5.8 Valve dead angle,
A0
The
α
0
setting is made for Metso segment and ball valves.
This setting takes into account the "dead angle"
α
0
of the
ball valves. The entire signal range is then used for effective
valve opening 90° -
α
0
. Use 0 % as the "dead angle" for the
valves not mentioned in Table 7.
NOTE:
Perform valve calibration always when
VTYP
has been
changed.
NOTE:
Perform valve calibration always when
ATYP
has been
changed.
NOTE:
Perform valve calibration always when controller fail
action parameter has been changed.
NOTE:
Perform valve calibration always when
ROT
has been
changed.
Fig. 24
Principle of setting, ND9000H and ND7000H
Fig. 25
Principle of setting, ND9000F and ND9000P
Fig. 26
Dead angle
100
80
60
40
20
0
0
20
40
60
80
100
POSITION
INPUT SIGNAL
= Basic setting
setting
Increasing input signal closes valve
Increasing input signal opens valve
cut-off safety range 2 ± 0.5 %
100
80
60
40
20
0
0
20
40
60
80
100
α0
Position
Input signal
low cut-off safety range 2 ± 0.5 %
Basic setting
α
0
setting
