Eaton VICKERS DG3V-10 Series, Overhaul Manual

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3. Reducer Module (Fig 10): The reducer module is
required for Air Gap and Wet Armature piloted models when
pilot pressure exceeds 210 bar (3000 psi). These two-stage
spool valves maintain a reduced outlet pressure against
variations in inlet pressure. These valves are able to act as
relief valves (at 50% of the maximum flow) to prevent excess
pressure being developed when an actuator is subject to a
reactive load.
4. Fast Response Option: Some applications require the
main stage spool to shift at a faster than normal rate. For
such applications, the fast response option is used. This
option requires the removal of an orifice plug within the main
stage body. When the orifice plug is removed, larger volumes
of fluid will enter the pilot valve section. When the pilot valve
shifts, the main stage spool responds at a faster rate. However,
this also generates transients that increase system shock.
For this reason, the fast response option is not recommended
when pilot pressures exceed 210 bar (3000 psi). Fast
response models have the letter ‘‘X’’ stamped into the unit
nameplate (i.e. DG5V-10-062**X-51). Table 2 compares
standard shift times to the fast response option. Figures 21
through 26 show the location of the orifice plugs that must be
removed for the fast response option.
1
2
5
4
3
7
6
8
9
11
10
12
13
14
16
15
17
Part No. Part Name
1
2
3
4
5
6
7
8
9 Plug
Back-up Ring
‘‘O’’ Ring
‘‘O’’ Ring
Spool
Body
Ball (2)
Spring Rest
Spring
Part No. Part Name
10
11
12
13
14
15
16
17 Spring Rest
‘‘O’’ Ring
Spring Housing
‘‘O’’ Ring
Adjuster Housing
Adjuster
Nut
Dowel Pin
Figure 10. Reducer Module
Table 2. Shift Response Times w/CETOP 3 Pilot (Fast Response option not available)
Valve Type Condition Pilot Pressure
10 bar (150 psi)
Pilot Pressure
100 bar (1500 psi)
Pilot Pressure
210 bar (3000 psi)
Voltage Voltage Voltage
‘‘AC’’ ‘‘DC’’ ‘‘AC’’ ‘‘DC’’ ‘‘AC’’ ‘‘DC’’
3–Position Spring Centered
Pilot Pressure Applied
Shift from Center to Offset
50
mS
80
mS
45
mS
60
mS
35
mS
55
mS
2–Position Spring Offset
Pilot Pressure Applied
Shift from Offset to Offset
200
mS
210
mS
90
mS
130
mS
75
mS
100
mS
3–Position Spring Centered
Pilot Pressure Removed
Shift from Offset to Center
50
mS
75
mS
50
mS
75
mS
50
mS
75
mS
2–Position Spring Offset
Pilot Pressure Removed
Shift from Offset to Offset
50
mS
80
mS
50
mS
80
mS
50
mS
80
mS
Table 2. Shift Response Times w/CETOP 5 Pilot (Fast Response option not available for pilot pressures over 140 bar (2000 psi)
Valve Type Condition Pilot Pressure
10 bar (150 psi)
Pilot Pressure
100 bar (1500 psi)
Pilot Pressure
210 bar (3000 psi)
Voltage Voltage Voltage
‘‘AC’’ ‘‘DC’’ ‘‘AC’’ ‘‘DC’’ ‘‘AC’’ ‘‘DC’’
3–Position
Spring Centered
Pilot Pressure Applied - Shift from Center to Offset
(Standard/Fast Response)
50/50
mS
80/80
mS
45/25
mS
75/60
mS
37/NA
mS
70/NA
mS
2–Position
Spring Offset
Pilot Pressure Applied - Shift from Offset to Offset
(Standard/Fast Response)
185/175
mS
240/190
mS
85/70
mS
130/125
mS
50/NA
mS
115/NA
mS
3–Position Spring
Centered
Pilot Pressure Removed - Shift from Offset to Center
(Standard/Fast Response)
50
mS
80
mS
50
mS
80
mS
50
mS
80
mS
2–Position Spring
Offset
Pilot Pressure Removed - Shift from Offset to Offset
(Standard/Fast Response)
75
mS
110
mS
50
mS
110
mS
30/NA
mS
110/NA
mS
‘‘DC’’ pilot runs without arc suppression devices. If diodes or other devices are used, de–energize times will be longer.