Samson 4708-5352 Service manual

Supply Pressure Regulators
Type 4708
Mounting and
Operating Instructions
EB 8546 EN
Edition June 2012
Fig. 1 · Supply pressure regulators
Type 4708-1152 with filter receptacle
Type 4708-5352 on Type 3730 Positioner
Type 4708-6252 on Type 3372 Actuator

Contents Page
1 Design and principle of operation. . . . . . . . . . . . . . . . . . . . 4
1.1 Versions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
1.2 Technical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
2 Mounting the supply pressure regulator. . . . . . . . . . . . . . . . . 8
2.1 Compact supply pressure regulator . . . . . . . . . . . . . . . . . . . 8
2.1.1 Direction of flow . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
2.1.2 Turning the supply pressure regulator . . . . . . . . . . . . . . . . . . 9
2.2 Supply pressure regulators for attachment to positioners and actuators. . 10
3 Pneumatic connections . . . . . . . . . . . . . . . . . . . . . . . . 14
3.1 Pressure gauge . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
3.2 Additional connection for a solenoid valve . . . . . . . . . . . . . . . 15
3.3 Manual/automatic transfer. . . . . . . . . . . . . . . . . . . . . . . 18
3.3.1 Mounting on positioners . . . . . . . . . . . . . . . . . . . . . . . . 18
3.3.2 Mounting using an adapter plate. . . . . . . . . . . . . . . . . . . . 19
3.3.3 Operating the manual/automatic transfer . . . . . . . . . . . . . . . 20
3.4 Filter with filter receptacle . . . . . . . . . . . . . . . . . . . . . . . 20
3.4.1 Mounting the air filter . . . . . . . . . . . . . . . . . . . . . . . . . 20
3.5 Rotatable supplementary filter . . . . . . . . . . . . . . . . . . . . . 21
3.5.1 Mounting the rotatable supplementary filter. . . . . . . . . . . . . . . 21
4 Set point adjustment . . . . . . . . . . . . . . . . . . . . . . . . . 22
5 Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
6 Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
6.1 Spare parts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
7 Accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
8 Dimensions in mm. . . . . . . . . . . . . . . . . . . . . . . . . . . 25
2EB 8546 EN
Contents

EB 8546 EN 3
Safety instructions
General safety instructions
4
The supply pressure regulators may only be mounted, started up or serviced
by fully trained and qualified personnel, observing the accepted industry
codes and practices. Make sure employees or third persons are not exposed
to any danger. All safety instructions and warnings in these mounting and
operating instructions, particularly those concerning assembly, start-up and
maintenance, must be observed.
4
Proper shipping and appropriate storage of the regulators are assumed.

1 Design and principle of
operation
The supply pressure regulator is used to sup-
ply pneumatic measuring and control equip-
ment with a constant air supply.
The maximum 12 bar pressure of the com-
pressed air network in a plant is reduced to
an adjustable minimum pressure of 0.2 to
1.6 bar or 0.5 to 6 bar.
At the inlet side, the supply pressure regula-
tor is equipped with a filter cartridge with a
mesh size of 20 µm. In addition, the regula-
tor can also be equipped with a filter recep-
tacle and a pressure gauge on the outlet
side.
The compressed air at the inlet flows across
the filter and through the free cross-sectional
area between the seat (1.1) and plug (1.2).
It leaves the outlet with a reduced pressure
depending on the plug position.
The output pressure to be controlled is trans-
ferred through the bore (1.3) to the operat-
ing diaphragm (2) where it is converted into
a positioning force. This force is used to
move the valve plug depending on the force
of the positioning spring (4).
Turning the set point screw (7) causes the
spring force to change and, as a result, the
required set point is adjusted.
The set point ranges of the supply pressure
regulator from 0.2 to 1.6 bar and 0.5 to
6 bar are determined by various tensions of
the installed positioning spring (4).
Condensed water contained in the com-
pressed air can be collected and drained
when the filter cartridge (9) is mounted hori-
zontally or the filter receptacle (12) is sus-
pended downwards. The stopper (10) can
be unscrewed or the manual drainage can
be activated (drain plug (15) in old versions)
to drain condensed water.
Note: Tighten the drain plug by hand only.
The maximum permissible tightening torque
is 3 Nm.
4EB 8546 EN
Design and principle of operation

EB 8546 EN 5
Design and principle of operation
15
1.11 1.2 1.3 2 3 4 5 6 7 8
9
10
10.1
11
11.1
12.1
12
13
9
16
Fig. 2 · Sectional drawings
1 Body
1.1 Seat
1.2 Plug
1.3 Bore in body
2 Operating diaphragm
3 Venting bore
4 Positioning spring
5 Cap
6 Lock nut
7 Set point screw
8 Adjustment knob
(accessories in Section 7)
9 Filter cartridge
10 Stopper
11 Bushing
11.1 Gasket
12 Filter receptacle
12.1 Gasket
13 Screw
15 Drain plug (max. 3 Nm)
16 Manual drainage
Old version
Adapter plate/connecting plate
Diverting gasket

1.1 Versions
Standard version Type 4708- xxxx
Filter on aluminum basis without
filter receptacle 10
With plastic filter receptacle 11
With aluminum filter receptacle 12
Stainless steel supply pressure regulator
Filter on stainless steel basis with
stainless steel receptacle 13
With plastic filter receptacle 14
Without filter receptacle 17
Connection
G ¼ 2
¼-18 NPT 5
Set point range 0.5 to 6 bar (8 to 90 psi)
Without pressure gauge 0
With pressure gauge,
completely free of copper 1
With pressure gauge,
copper-free housing 2
Set point range 0.2 to 1.6 bar (3 to 23 psi)
Without pressure gauge 3
With pressure gauge, comple-
tely free of copper 4
With pressure gauge,
copper-free housing 5
Supply pressure regulator with adapter plate
for positioners
Type 3730, 3766, 3767, 3780,
3785, 3787 53
Type 3730, 3766, 3767, 3780,
3785, 3787 54
Type 4763/4765 55 0
Type 3760 57
Type 3761 58
Supply pressure regulator with adapter plate
for pneumatic actuators
Type 3277 (240 to 700 cm²)
with Type 3730, 3766, 3767,
3780, 3785 or 3787 Positioner
62 0
Type 3372 62
Type 3277 with connection
block 64
Manual/automatic transfer
Bypass for positioner 82
Filter without pressure gauge
Type 4708- xxx0
Aluminum housing and plastic
filter receptacle 83 0
Aluminum housing and alu-
minum filter receptacle 84 0
Stainless steel housing and
plastic filter receptacle 86 0
Stainless steel housing and
stainless steel filter receptacle 87 0
6EB 8546 EN
Design and principle of operation

1.2 Technical data
EB 8546 EN 7
Design and principle of operation
Supply pressure regulator Type 4708-xx
Supply pressure 1 bar (15 psi) above the adjusted set point,
however, at least 1.6 bar (24 psi) · Max. 12 bar (180 psi)
Output pressure Adjustable from 0 to 1.6 bar (0 to 24 psi) or 0 to 6 bar (0 to 90 psi)
Set point range 0.2 to 1.6 bar (3 to 24 psi) or 0.5 to 6 bar (8 to 90 psi)
Air consumption £0.05 mn3/h (with 7 bar supply air)
Permissible ambient
temperature
(values in brackets apply to
low-temperature version)
–25 to 70 °C (–50 to 70 °C) for Types 4708-11, -14, -45, -83, -86
–25 to 80 °C (–40 to 80 °C) for Type 4708-64
–25 to 80 °C (–50 to 80 °C) for Types 4708-10, -12, -13, -17, -53, -54, -55, -57,
-58, -62, -82, -84, -87
(–30 °C possible, but in this case, air consumption reaching up to 0.3 mn3/h with
7 bar supply pressure)
Input pressure dependance < 0.01 bar/Dp = 1 bar
Reversing error 0.1 bar to 0.4 bar (depending on the set point)
Hysteresis < 0.1 bar
Pressure gauge Ø40
indication range 0 to 1.6 bar (0 to 24 psi) or 0 to 6 bar (0 to 90 psi) Connection G 18
Type 4708- 10 11 12 13 14 17 53 54 55
Weight, approx. 0.48 0.58 0.66 1.65 1.2 1.0 0.68 0.95 0.37
Type 4708- 57 58 62 64 82 83 84 86 87
Weight, approx. 0.47 0.4 0.4 0.5 0.4 0.24 0.32 0.59 0.95
Materials
Body Polyamide, glass fiber reinforced
Adapter plate Aluminum alloy, anodized black
Stopper and gasket Polyamide, glass fiber reinforced and NBR
Cover Polyamide, glass fiber reinforced
Cap Polyamide, glass fiber reinforced
Plug Polyamide, glass fiber reinforced and polyoxymethylene
Plug sealing NBRT and VMQ
Diaphragm NBR
Diaphragm plate Polyamide, glass fiber reinforced
Filter cartridge 20 µm: Polypropylene · 5 µm: Stainless steel
Pressure gauge Housing
Connection Stainless steel St. steel (version free of copper) Brass, nickel-plated

2 Mounting the supply
pressure regulator
To prevent excessive amounts of condensed
water from collecting, the distance between
the compressor and supply pressure regula-
tor should be kept as short as possible.
Make sure the drain plug faces downwards
in versions with a filter receptacle.
2.1 Compact supply pressure
regulator
The supply pressure regulator can either be
mounted directly in the pipeline of the air
supply or on rails or brackets using the cor-
responding mounting parts (see accessories
table in section 7).
Observe the direction of flow of the supply
air. An arrow on the nameplate indicates
the direction.
2.1.1 Direction of flow
In the compact supply pressure regulators
4708-10xx/-11xx/-14xx and -17xx the
direction of flow can be changed as follows:
1. Unscrew both fixing screws and lift the
supply pressure regulator off its connect-
ing plate.
2. Remove the diverting gasket, turn it
180 degrees and reposition it as shown
in Fig. 3.
Note: The long rubber finger of the gas-
ket must always point in the direction of
the regulator outlet.
3. Fasten the supply pressure regulator
onto the connecting plate.
4. Stick the enclosed adhesive label over
the arrow of the nameplate, ensuring the
arrow indicates that the supply air flows
in the opposite direction.
8EB 8546 EN
Mounting the supply pressure regulator
G
4708-112.
06
3-....
06
3-....
4708-112.
G
Fig. 3 · Changing the direction of flow in compact supply pressure regulators
Connecting plate
Standard label Diverting gasket Connecting plate
Label with arrow
Fixing screws
Long rubber finger always pointing towards the regulator outlet
Supply
pressure
regulator

2.1.2 Turning the supply pressure
regulator
The supply pressure regulator can be turned
on its connecting plate to allow the set point
screw to face either up or down.
1. Unscrew both fixing screws and lift the
supply pressure regulator off its connect-
ing plate.
2. Pull the diverting gasket out of the regu-
lator and keep it in this position.
3. Turn the regulator 180 degrees and re-
insert the gasket. In this way, you keep
the bore assignment of the gasket for
supply air input and regulator outlet.
Note: The long rubber finger of the gas-
ket must always point in the direction of
the regulator outlet (reduced supply
pressure).
4. Fasten the regulator onto the connecting
plate.
EB 8546 EN 9
Mounting the supply pressure regulator
Fig. 4 · Turning the supply pressure regulator on its connecting plate or adapter plate
Supply air input
Connecting plate or adapter plate
Supply air input
(Supply) >
Regulator facing downward
Diverting gasket
Long rubber finger
always pointing
towards outlet
Regulator facing upward
Fixing screws
Regulator outlet
Diverting gasket
Front and back view
Regulator outlet (long rubber finger)
Supply air input
depending on the
position of the
gasket

2.2 Supply pressure regulators
for attachment to positioners
and actuators
The supply pressure regulator versions in-
tended for attachment to positioners and ac-
tuators are equipped with various adapter
plates for the attachment.
If required, the installation position of the
supply pressure regulator can be changed
by turning it 180° on its adapter plate to al-
low the set point screw/adjustment knob to
face either up or down. This applies particu-
larly for positioners which can be attached
either to the left or right side of the valve
yoke to determine the operating direction
and fail-safe action of the actuator.
To turn the supply pressure regulator, pro-
ceed as described for the compact supply
pressure regulator in section 2.1.2. The reg-
ulator is turned on its adapter plate instead
of on the connecting plate.
Regulators for Types 3730/3766/3767/
3780/3785/3787 Positioners
Type 4708-53xx for Type 3271 Actuator
and Type 3277 Actuator with 120 cm² as
well as 240 to 700 cm² with hooked-up
valve accessories.
1. Insert the gasket (2) into the recess of the
adapter plate (1).
2. Place the supply pressure regulator on
the positioner on the side where the
pneumatic connections SUPPLY and
OUTPUT are located. Screw tight using
both M5 screws (3).
Type 4708-54xx for rotary actuators.
Proceed to mount as Type 4708-53xx.
Type 4708-54xx has a second output
sealed with a stopper. This is intended for
reduced supply air. It can be used to supply
a second device, if required (e.g. a pilot-op-
erated solenoid valve).
10 EB 8546 EN
Mounting the supply pressure regulator
Fig. 5 · Attachment onto positioners
Type 4708-53xx
73
194
111
Type 4708-54xx

Type 4708-55xx for Type 4763 and
Type 4765 Positioner
1. Screw the special nuts (5) into the con-
necting holes of the positioner.
2. Insert the gasket (2) into the recess of the
adapter plate (1).
3. Push the special hollow screws (6) for
SUPPLY and (7) for OUTPUT into the
connecting holes of adapter plate (1).
4. Place the supply pressure regulator onto
the positioner and fasten it using both
special screws.
5. Seal the spare connections with stoppers
(4) to prevent dirt from entering the de-
vice.
Type 4708-57xx for Type 3760 Positioner
The attachment for a positioner mounted on
the left side of the valve yoke (seen from the
black switchover plate) is shown. For a
positioner mounted on the right side, the
adapter plate is attached in the same way,
except the supply pressure regulator must be
turned by 180° (see bottom of page 28).
1. Screw the special nuts (5) into the con-
necting holes of the positioner.
2. Insert the O-rings (9) into the recess of
the adapter plate (1).
3. Push the special hollow screws (6) for
SUPPLY and (7) for IN. SIGNAL into
connecting holes of adapter plate (1).
4. Place the supply pressure regulator onto
the positioner and fasten it using both
special screws.
5. Seal the IN. SIGNAL connection of i/p
positioner with stainless steel stopper
(10).
6. Seal the spare connections with stoppers
(4) to prevent dirt from entering the de-
vice.
EB 8546 EN 11
Mounting the supply pressure regulator
6
0
SAMSON 4763
4708-552.
6
0
G
1
7
6
5
5
2
1
4
4
10
1
7
9
6
1
5
5
Fig. 6 · Attachment to positioners
Switchover
plate

Type 4708-58xx for Type 3761 Positioner
1. Screw the special nut (5) into the SUPPLY
connecting hole of the positioner.
2. Push the special hollow screw (6) into
the connection hole of the adapter plate
(1).
3. Insert the O-ring (9). Position the supply
pressure regulator and fasten it to the
positioner using the special screw.
4. Seal the spare connections with stoppers
(4) to prevent dirt from entering the de-
vice.
Type 4708-64xx for Type 3277 Actuator
Before attaching the supply pressure regula-
tor, check whether the tongue of the gasket
(1.2) is aligned at the connection block (1)
in such a way that the actuator symbol (1.3)
indicating “Actuator stem extends” or “Actu-
ator stem retracts” matches the fail-safe ac-
tion of the actuator.
If this is not the case, proceed as follows:
1. Unscrew the three Phillips screws (3.1),
lift off the cover plate (1.1) and turn the
gasket (1.2) by 180° and reinsert it.
2. Place the connection block with inserted
O-ring on the positioner and actuator
yoke and fasten it with hexagonal socket
screw (3).
3. Place the supply pressure regulator with
O-ring on the connection block and fas-
ten it with hexagonal socket screw (2).
12 EB 8546 EN
Mounting the supply pressure regulator
3
1
1.1
1.2
1.3 3.1
3.1
2 1
G3/8
138
238
G
Output Output
SInput
6
5
432
1
0
27
1
6
9
4
1
5
Fig. 7 · Attachment of supply pressure regulator

Type 4708-62xx for Type 3372 Actuator
1. Screw the special nut (5) into the SUPPLY
connecting hole of the actuator.
2. Push the special hollow screw (6) into
the connecting hole of the adapter plate.
3. Insert the O-ring (9). Position the supply
pressure regulator and fasten it onto ac-
tuator using the special screw.
4. Seal the spare connections with stoppers
(4) to prevent dirt from entering the de-
vice.
EB 8546 EN 13
Mounting the supply pressure regulator
1
9
5
6
4
1
6
5
94
Fig. 8 · Attachment to Type 3372 Actuator

3 Pneumatic connections
The pneumatic connections are designed ei-
ther as G ¼ or ¼ NPT-18 threads. On com-
pact supply pressure regulators, an arrow
on the adhesive label indicates the direction
from the supply air input to the output.
In supply pressure regulators with two con-
necting holes in the adapter plate (Figs. 5
and 6, top), the supply air connection is
marked SUPPLY. The positioner's output sig-
nal is routed in these versions over the
OUTPUT port through the adapter plate to
the actuator.
3.1 Pressure gauge
Mount the pressure gauge in such a way
that there is a 2-3 mm gap between the lock
nut and pressure gauge's square end after
tightening the lock nut (20).
In the compact versions (Type 4708-12xx/
-13xx), make sure additionally that the
stopper (23) is only screwed in to the point
where it becomes aligned with the housing,
otherwise the gaskets (21, 22) will be dam-
aged. Each gasket is assigned either to the
pressure gauge or to the stopper and must
be changed correspondingly if you change
the location of the pressure gauge and
stopper to the other side.
14 EB 8546 EN
Pneumatic connections
20 22
2...3 mm 0 mm
21 23
Fig. 9 · Pressure gauge attachment, e.g. with Type 4708-12xx/13xx Supply Pressure Regulators

3.2 Additional connection for a
solenoid valve
An additional output for reduced air pres-
sure is required to allow the supply pressure
regulator to supply two pneumatic devices.
In some versions of Type 4708 (see sec-
tion 7 on accessories), a second output can
be made available by using an intermediate
plate.
Example: Pneumatic actuator with positioner
and pilot-operated solenoid valve ÞSupply
air must be supplied separately to the pilot
control.
The reduced supply pressure of the supply
pressure regulator is additionally routed to
the threaded connection at the side over the
corresponding holes in the intermediate
plate. All supply pressure regulators have
the same intermediate plate, except for
Type 4708-57xx, designed for attachment
to Type 3760 Positioner (Fig. 12), its inter-
mediate plate has a different hole assign-
ment for the air ducts.
All versions can be ordered made of alumi-
num or stainless steel and with either G or
NPT threads. See section 7 for more details.
EB 8546 EN 15
Pneumatic connections
1
1.1
A
A
A
A
E
SUPPLY
2
2.1
3
4
4.1
E
E
E
Fig. 10 · Mounting an intermediate plate for Types 3730/3766/3767/3780 Positioners
Intermediate plate (2) with
additional connection
Output for
reduced supply air

Mounting the intermediate plate
1. Remove the fixing screws and lift the
supply pressure regulator (4) together
with the diverting gasket (3) off the
adapter plate (1).
Make sure you do not change the posi-
tion of the diverting gasket in the supply
pressure regulator.
Note: The long rubber finger of the diverting
gasket (3) must always point in the direction
of the regulator outlet (reduced supply air).
See Figs. 10, 11 and 12.
2. Insert O-rings (2.1) in the holes of the in-
termediate plate (2).
3. Place the intermediate plate onto the
adapter plate in such a way that the
three holes located next to one another
are positioned over both 5 mm holes on
16 EB 8546 EN
Pneumatic connections
1
1.1
E
AM
A
2
2.1
3
4
4.1
A
A
E
A
E
A
E
Fig. 11 · Mounting an intermediate plate on Type 3372 Actuator
Output for
reduced supply air
Supply air input
Intermediate
plate (2)

the adapter plate and the bores (1.1) for
the fixing screws are aligned.
4. Place the supply pressure regulator (4)
with the diverting gasket (3) onto the in-
termediate plate (2). Insert the longer fix-
ing screws and fasten the parts.
EB 8546 EN 17
Pneumatic connections
SUPPLY
AM
A
2
1
2.1
1.1
E
E
3
E
4
4.1
E
A
A
A
A
Fig. 12 · Mounting an intermediate plate on Type 3760 Positioner

3.3 Manual/automatic transfer
The positioner output is routed to the actua-
tor over the manual/automatic transfer. In
automatic mode, the positioner is in
closed-loop operation. In manual mode, the
output pressure of any supply pressure regu-
lator is directly applied to the actuator. This
creates a manual bypass for the positioner.
The manual/automatic transfer unit is
mounted directly onto Types 376x, 378x
and 373x (Fig. 14) or on an adapter plate
with hook-up to the actuator (Fig. 13).
The Type 4708-53 (Fig. 15) or Type
4708-54 Supply Pressure Regulator can be
fastened onto the regulator. All other supply
pressure regulators can be connected to the
manual/automatic transfer by a piping
(hook-up).
3.3.1 Mounting on positioners
4Insert flat gasket into recess of the man-
ual/automatic transfer unit (Fig. 14).
4Fasten manual/automatic transfer unit to
the positioner using the two hexagon
socket screws.
4Connect hook-up to the Supply and Out-
put connections of the manual/automatic
transfer unit.
18 EB 8546 EN
Pneumatic connections
1
Output (38)
Supply (9)
2
3
4
Supply
Output
Fig. 13 · Mounting the manual/automatic transfer using an adapter plate
1 Pneumatic control
valve with positioner
2 Adapter plate
1400-9605 (G)
1400-9606 (NPT)
3 Manual/automatic
transfer
Type 4708-82
in AUTO mode
4 Supply pressure regu-
lator with filter
(e.g. Type 4708-10)
Fig. 14 · Mounting on a positioner

Optionally, a Type 4708-53 Supply Pres-
sure Regulator can be mounted upstream of
the manual/automatic transfer unit
(Fig. 15).
3.3.2 Mounting using an adapter
plate
4Fasten adapter plate, for example to a
NAMUR rib using a hexagon socket
screw.
4Fit the flat gasket on the manual/auto-
matic transfer unit. Fasten it to the
adapter plate using the two hexagon
socket screws.
4Connect hook-up for positioner and actu-
ator as shown in Fig. 13.
EB 8546 EN 19
Pneumatic connections
Fig. 15 · Type 4708-82 Manual/Automatic Transfer
Unit, Type 4708-53 Supply Pressure
Regulator with pressure gauges and
rotatable filter receptacle
Fig. 16 · Mounting using adapter plate

3.3.3 Operating the manual/
automatic transfer
In normal operation, the manual/automatic
transfer runs in automatic mode, during
which the positioner supplies air to the
pneumatic actuator.
To switch to manual mode, twist off the plas-
tic cap. Turn the switchover pin counter-
clockwise and pull it (approx. 1 cm) out of
the bayonet lock. The compressed air is then
routed directly from the supply pressure reg-
ulator or from the air supply network to the
pneumatic actuator.
To switch back to automatic mode, push in
the switchover pin again. To do this, insert
the lock pin completely into the bayonet and
lock it. Replace plastic cap and tighten.
3.4 Filter with filter receptacle
The Types 4708-83, 4708-84, 4708-86
and 4708-87 Air Filters are designed for
universal use. They have either G ¼ or
¼-18 NPT threaded connections.
3.4.1 Mounting the air filter
Mount the air filter directly into the pipeline,
while ensuring the direction of flow (printed
on the device) is kept.
The filter receptacle must face downwards to
function correctly.
20 EB 8546 EN
Pneumatic connections
Fig. 17 · Cap and switchover pin Fig. 18 · Types 4708-83 to -87 Air Filters