Samson Type 4708 Service manual

Supply Pressure Regulator
Type 4708
Mounting and
Operating Instructions
EB 8546 EN
Edition February 2005
Fig. 1 · Supply pressure regulators
Type 4708-5352 on Type 3730 Positioner
Type 4708-6252 on Type 3372 Actuator
Type 4708-1152 with filter receptacle

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
4 Set point adjustment . . . . . . . . . . . . . . . . . . . . . . . . . 18
5 Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
6 Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
7 Accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
8 Dimensions in mm . . . . . . . . . . . . . . . . . . . . . . . . . . 20
2EB 8546 EN
Contents

EB 8546 EN 3
Safety instructions
General safety instructions
4
The supply pressure regulator 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 regulator 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 input side, the supply pressure regu-
lator is equipped with a filter cartridge with
a mesh size of 20 µm. In addition, the regu-
lator can also be equipped with a filter re-
ceptacle and a pressure gauge on the outlet
side.
The compressed air at the input flows across
the filter and through the free cross-sectional
area between the seat (1.1) and plug (1.2).
It leaves the output with a reduced pressure
depending on the plug position.
The output pressure to be controlled is trans-
ferred via the bore (1.3) to the operating di-
aphragm (2) where it is converted into a po-
sitioning 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) or
drain plug (15) can be unscrewed to drain
condensed water.
4EB 8546 EN
Design and principle of operation

EB 8546 EN 5
Design and principle of operation
Fig. 2 · Sectional drawings
1.11 1.21.3 2 3 4 5 6 7 8
9
11
11.1
12.1
12
13
9
15
10
10.1
Adapter plate/connecting plate
Diverting gasket
1 Body
1.1 Seat
1.2 Plug
1.3 Bore
2 Operating diaphragm
3 Venting bore
4 Positioning spring
5 Cap
6 Lock nut
7 Set point screw
8 Adjustment knob
9 Filter cartridge
10 Stopper
11 Bushing
11.1 Gasket
12 Filter receptacle
12.1 Gasket
13 Screw
15 Drain plug

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
63 0
Type 3372 62
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 Adustable 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 –20 to 70 °C (–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 / ∆p = 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 1/8
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 63 83 84 86 87
Weight, approx. 0.47 0.4 0.4 0.87 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 Polypropylene
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 table in
section 7 on page 19).
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 output.
3. Screw the supply pressure regulator tight
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
Fig. 3 · Changing the direction of flow in compact supply pressure regulators
G
4708-112.
06
3-....
06
3-....
4708-112.
G
Connecting plate
Standard label
Gasket Connecting plate
Label with arrow
Fixing screws
Long rubber finger always pointing towards the regulator output
Supply
pressure
reglulator

2.1.2 Turning the supply pressure
regulator
The supply pressure regulator can be turned
on its connecting plate to allow the set point
adjuster 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 output.
Note! The long rubber finger of the gas-
ket must always point in the direction of
the regulator output (reduced supply
pressure).
4. Screw the regulator tight onto the con-
necting 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 output
Regulator facing upward
Fixing screws
Regulator output
Diverting gasket
Front and back view
Regulator output (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 adjustment knob to face either up or
down. This applies particularly for
positioners which can be attached either to
the left or right side of the valve yoke to de-
termine 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 up
to 700 cm2and Type 3277 Actuator with
120 cm2as well as 240 to 700 cm2with
hooked-up 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).
3. Close the spare connections with
stoppers (4) to prevent dirt from entering
the device.
Type 4708-54xx for Type 3271 Actuator
with 1400 and 2800 cm2or single-acting
rotary actuators.
Proceed to mount as for Type 4708-53xx.
10 EB 8546 EN
Mounting the supply pressure regulator
Fig. 5 · Attachment onto positioners
Type 4708-53xx
Type 4708-54xx
73
192
109
4708-535.
6
0
06
NPT
1
2
3
4
1