22
7 VG9H 70 en
ring properly. The screws guide the prestage body
into the correct position. Tighten the screws (139)
evenly.
Push the prestage 2-pole wire connector into the
socket on the connector board (182). The wire connec-
tor can only be fitted in the correct position. Replace
the inner cover (39) and tighten the M3 screws.
5.3
Spool valve
5.3.1
Restricted and standard capacities
Restricted capacity means the spool valve option 12 and
standard capacity means the spool valve option 15 in VG
type coding. See type coding in the machine plate for
details.
5.3.1.1 Removal
For spool valve removal it is usually necessary to unmount
the ValvGuard from the actuator.
Before removing the spool valve assembly in
VG931_, the spool valve cover (454) needs to be
removed. Unscrew the M4 screws (4 pcs.).
Working from the bottom side of the ValvGuard,
unscrew the M5 screws (4 pcs.). Remove the spool
valve (420) with gasket (63). Do not remove the
spool valve adapter plate (421).
5.3.1.2 Installation
Mount the spool valve (420) to the housing, and
tighten the four M5 screws evenly.
Mount the spool valve cover (454) (only in
VG931_).Tighten the four M4 screws evenly.
5.3.2
High capacity
High capacity spool valve means the spool valve options 35
or 37 in VG type coding. See type coding in the machine
plate for details.
5.3.2.1 Removal
Unscrew the M5 screws (4 pcs.). Remove the spool
valve (420) with gasket from the mounting block
(421).
5.3.2.2 Installation
Ensure that the gasket (63) is properly located in the
grooves in the bottom of the spool valve. Mount the
spool valve (420) to the mounting block (421), and
tighten the four M5 screws evenly.
5.4
Communication circuit board
5.4.1
Removal
Loosen the M8 stop screw (110) in the position indi-
cator (109) and turn the position indicator from the
shaft (11). Remove the inner cover (39) attached with
M3 screws (42, 3 pcs.).
Remove the M3 screws (217, 4 pcs.). Hold the sides of
the circuit board and lift it directly upwards and out-
wards. Handle the board carefully, touching only the
sides.
5.4.2
Installation
Mount the new communication circuit board care-
fully.
Locate the pins with the matching connector on the
board. Tighten the M3 screws (217) evenly.
Install the inner cover (39).
Mount the position indicator (109) on the shaft and
tighten the M8 stop screw (110) temporarily. The
final orientation and locking of the position indicator
should be done after installation of the ValvGuard to
the actuator.
NOTE:
Spool valve cannot be changed in the field.
NOTE:
If the maintenance operations are needed for the spool
valve, it is advised to replace the whole spool valve assem-
bly with a spare unit.
NOTE:
If adapter plate (421) is lifted away from its place, special
attention must be paid to ensure that gasket (174) and pipe
(431) are properly attached to the housing. O-rings of the
pipe must be handled carefully in order to avoid breakage.
Fig. 25
Spool valve assembly
NOTE:
Communication circuit board cannot be changed in the
field.
NOTE:
Ground yourself on the body of the device before touch-
ing the circuit board.
Ex WARNING:
Grounding of the circuit board is essential to explo-
sion protection.
The board is grounded to the housing by the mounting
screw next to the terminal blocks.
Fig. 26
Communication board
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