Metso ND9200H, Installation Maintenance And Operating Instructions, Page: 4 / 32

4
2 ND9200H INTELLIGENT VALVE
CONTROLLER WITH HART
COMMUNICATION
2.1 General
This manual incorporates Installation, Maintenance and
Operation Instructions for the Metso Automation
ND9200H intelligent valve controller. The ND9200H may
be used with either cylinder or diaphragm type pneu-
matic actuators for rotary or linear valves.
2.2 Technical description
The ND9200H is a 4–20 mA loop-powered microcontrol-
ler-based intelligent valve controller. The device operates
even at 3.6 mA input signal and communicates via HART.
The device contains a Local User Interface enabling
local configuration. A PC with FieldCare software can be
connected to the ND9200H itself or to the control loop.
The powerful 32-bit microcontroller controls the valve
position. The measurements include:
❑
Input signal
❑
Valve position with contactless sensor
❑
Actuator pressures, 2 independent measurements
❑
Supply pressure
❑
Spool valve position
❑
Device temperature
Advanced self-diagnostics guarantees that all measure-
ments operate correctly. Failure of one measurement
does not cause the valve to fail if the input signal and
position measurements are operating correctly. After
connections of electric signal and pneumatic supply the
micro controller (µC) reads the input signal, position sen-
sor (
α
), pressure sensors (Ps, P1, P2) and spool position
sensor (SPS). A difference between input signal and
position sensor (
α
) measurement is detected by the con-
trol algorithm inside the µC. The µC calculates a new
value for prestage (PR) coil current based on the infor-
mation from the input signal and from the sensors.
Changed current to the PR changes the pilot pressure to
the spool valve. Reduced pilot pressure moves the spool
and the actuator pressures change accordingly. The
spool opens the flow to the driving side of the double
diaphragm actuator and opens the flow out from the
other side of the actuator. The increasing pressure will
move the diaphragm piston. The actuator and feedback
shaft rotate clockwise. The position sensor (
α
) measures
the rotation for the µC. The µC using control algorithm
modulates the PR-current from the steady state value
until a new position of the actuator according to the input
signal is reached.
2.3 Markings
The valve controller is equipped with an identification
plate sticker (Fig. 2).
Identification plate markings from top to bottom include:
❑
Type designation of the valve controller
❑
Revision number
❑
Enclosure class
❑
Operational temperature
❑
Input signal (voltage range)
❑
Input resistance
❑
Maximum supply voltage
❑
Supply pressure range
❑
Contact details of the manufacturer
❑
CE mark
❑
Manufacturing serial number TTYYWWNNNN*)
*) Manufacturing serial number explained:
TT= device and factory sign
YY= year of manufacturing
WW = week of manufacturing
NNNN = consecutive number
Example: PH03011234 = controller, year 2003, week 1,
consecutive number 1234.
NOTE:
The selection and use of the valve controller in a specific
application requires close consideration of detailed
aspects. Due to the nature of the product, this manual
cannot cover all the likely situations that may occur when
installing, using or servicing the valve controller.
If you are uncertain about the use of the controller or its
suitability for your intended use, please contact Metso
Automation for more information.
Fig. 1 The principle of operation
Fig. 2 Identification plate
SV
S
LUI
PR
SPS
P
2
P
1
P
S
µ
C
α
Pos
50.2
4 - 20 mA + HART