Samson 4763 Service manual

Electropneumatic Positioner
Type 4763
Fig. 1 · Type 4763
Mounting and
Operating Instructions
EB 8359-2 EN
Edition September 2010

Contents
1 Design and principle of operation. . . . . . . . . . . . . . . . . . . . 6
2 Attachment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
2.1 Attachment to valves with cast yokes . . . . . . . . . . . . . . . . . . . 8
2.2 Attachment to valves with rod-type yokes . . . . . . . . . . . . . . . . 9
2.3 Cover of the positioner housing . . . . . . . . . . . . . . . . . . . . . 9
3 Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
3.1 Electrical connections . . . . . . . . . . . . . . . . . . . . . . . . . 10
3.2 Pneumatic connections . . . . . . . . . . . . . . . . . . . . . . . . . 11
3.2.1 Pressure gauges . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
3.2.2 Supply pressure . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
4 Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
4.1 Combining positioner and actuator. . . . . . . . . . . . . . . . . . . 12
4.1.1 Determining/reversing the operating direction . . . . . . . . . . . . . 12
4.2 Starting point and input signal (reference variable) . . . . . . . . . . . 14
4.3 Setting the positioner at the valve. . . . . . . . . . . . . . . . . . . . 15
4.3.1 Setting the air delivery (volume restriction Q) and proportional band XP . 15
4.3.2 Setting actuator version “Stem extends” . . . . . . . . . . . . . . . . 16
4.3.3 Setting actuator version “Stem retracts”. . . . . . . . . . . . . . . . . 16
4.4 Exchanging the range spring. . . . . . . . . . . . . . . . . . . . . . 17
5 Converting an electropneumatic into a pneumatic positioner . . . . . . 18
6 Servicing explosion-protected devices . . . . . . . . . . . . . . . . . 19
7 Maintenance, calibration and work on equipment . . . . . . . . . . . 19
8 Accessories and mounting parts . . . . . . . . . . . . . . . . . . . . 20
9 Dimensions in mm. . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Test certificates . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
2EB 8359-2 EN
Contents

EB 8359-2 EN 3
Safety instructions
General safety instructions
4
The positioner is to be mounted, started up or operated only by trained and
experienced personnel familiar with the product.
According to these Mounting and Operating Instructions, trained personnel
refers to individuals who are able to judge the work they are assigned to and
recognize possible dangers due to their specialized training, their knowledge
and experience as well as their knowledge of the applicable standards.
4
Explosion-protected versions of this positioner are to be operated only by
personnel who have undergone special training or instructions or who are
authorized to work on explosion-protected devices in hazardous areas. Refer
to section 6.
4
Any hazards that could be caused by the process medium, the operating
pressure, the signal pressure or by moving parts of the control valve are to be
prevented by means of the appropriate measures.
4
If inadmissible motions or forces are produced in the pneumatic actuator as a
result of the supply pressure, the supply pressure must be restricted by means
of a suitable supply pressure reducing station.
4
Proper shipping and appropriate storage are assumed.
4
Note: The device with a CE marking fulfils the requirements of the Directives
94/9/EC (ATEX) and 89/336/EEC (EMC).
The declaration of conformity is available on request.

4EB 8359-2 EN
Versions
Electropneumatic Positioner Type 4763- x1x00x x xx0x0xx0
Explosion protection
Without 0 2/7
II 2 G EEx ia IIC T6 acc. to ATEX 1
CSA/FM intrinsically safe/non incendive 3
II 3 G EEx nA II T6 for Zone 2 (ATEX) 8 2/7
Range spring
Range spring 1, travel = 15 mm 1
Range spring 2, travel = 30 mm,
split-range 15 mm 2
Range spring 3, travel = 60 mm,
split-range 30 mm 3
Pneumatic connections
ISO 228/1 G ¼ 1
¼-18 NPT 3
Electrical connection
Cable gland
M20 x 1.5 blue (plastic) 1
M20 x 1.5 black (plastic) 2
M20 x 1.5 (nickel-plated brass) 72
i/p module
Type 6109 1
Type 6112 2
Reference variable
4 … 20 mA 0
0 … 20 mA 22
1 … 5 mA 23
Temperature range
Standard 0
Low temperature down to –45 °C 22
Special version
None 000
For oxygen as the operating medium 0/1 0 1 6
II 3 D IP 54 T 80 °C (with
manufacturer’s declaration) 8 2/7 0 1 8

EB 8359-2 EN 5
Technical data
Type 4736 Positioner
Travel range 7.5 to 60 mm, with 90 mm lever extension
Reference variable
Split-range 0 to 50 %
and 50 to 100 %
Reference variable span
(up to 50 mm travel)
4 to 20 mA (Ex) Internal resistance Riat 20 °C approx. 250 W±
7 %
4 to 20 mA (not Ex) Internal resistance Riat 20 °C approx. 200 W±
7 %
0 to 20 mA Internal resistance Riat 20 °C approx. 200 W±
7 %
1 to 5 mA Internal resistance Riat 20 °C approx. 880 W±
7 %
Range spring See table on page 14
Supply air Supply air 1.4 to 6 bar (20 to 90 psi)
Air quality acc.
to ISO 8573-1
(2001)
Maximum particle size and density: Class 4 · Oil content: Class 3
Pressure dew point: Class 3 or at least 10 K below the ambient temperature to
be expected
Output signal pressure pst Max. 0 to 6 bar (0 to 90 psi)
Characteristic Linear · Deviation from terminal-based conformity: £1.5 %
Hysteresis < 0.5 %
Sensitivity < 0.1 %
Operating direction Reversible
Proportional band Xp
(at 1.4 bar supply air)
1 to 3 % with spring 1 or 2
1 to 1.5 % with spring 3
Air consumption in
steady state, Xp= 1 % With 1.4 bar supply air: 0.19 mn³/h With 6 bar supply air: 0.5 mn³/h
Air output capacity At Dp 1.4 bar: 3.0 mn³/h At Dp 6 bar: 8.5 mn³/h
Transit time for Type 3271
“Stem extends” 240 cm²: £1.8 s · 350 cm²: £2.5 s · 700 cm²: £10 s
Permissible ambient
temperature
–20 to 70 °C;
With metal cable gland: –35 to 70 °C
Special version: –45 to 80 °C
The limits specified in the EC Type Examination Certificate additionally apply
for explosion-protected devices.
Version with oxygen as operating medium up to max. 60 °C
Influences Temperature < 0.03 %/1 K
Supply air < 0.3 %/0.1 bar
Vibration: < 2 % between 10 and 150 Hz and 4 g
Effect when turned by 180°: < 3.5 %
Degree of protection IP 54 · Special version IP 65
Weight Approx. 1.2 kg
Materials Housing: Die-cast aluminum, chromated and plastic-coated
External parts: Stainless steel

1 Design and principle of
operation
The electropneumatic positioner is used for
the correlation between the valve stem posi-
tion (controlled variable x) and the input sig-
nal (reference variable w) received from the
controller. In this case, the input signal ac-
cepted from the control device is compared
to the travel (valve stem position) of the con-
trol valve, and a pneumatic signal pressure
(output variable y) is delivered.
The positioner consists of an i/p converter
unit (21) and the pneumatic section includ-
ing the lever (1), shaft (1.1) and range
spring (6), plus the control system compos-
ing nozzle, flapper and booster. The input
signal (e.g. 4 to 20 mA) is directly fed to the
i/p converter unit and converted to a pro-
portional air pressure signal pe. Any change
of the input current signal causes a propor-
tional change of the air pressure pesent to
the pneumatic control system.
The air pressure pe, in turn, produces a
force which acts on the surface of the mea-
suring diaphragm (8) and is compared to
the force of the range spring (6). The motion
of the diaphragm (8) is transferred to the
flapper (10.2) via the feeler pin (9.1), and
the nozzle (10.1) releases pressure. Any
change of either the air pressure peor the
valve stem position causes the pressure to
change in the booster (12) connected down-
stream of the nozzle. The signal pressure pst
which is released causes the plug stem to as-
sume a position based on the input signal.
The adjustable volume restriction Q (14) and
Xp (gain) restriction (13) are used to opti-
mize the control loop. The range spring (6),
which can be exchanged, is assigned to
both the rated valve travel and the nominal
voltage of the input signal.
6EB 8359-2 EN
Design and principle of operation
4
21 14 13 10.2 7
1
15
8
5 6.1 6 3
Fig. 2 · Positioner with cover removed

EB 8359-2 EN 7
Design and principle of operation
p
st
Output
36
p
e
Supply
9
21
1.1
4
5
6
8
9
9.1
10.2
10
10.1 6
8
9
9.1
10.2
10.1
10
11
ii
p
12
14
13
1 2 2.1 20
Fig. 3 · Functional diagram
Legend for Figs. 2 and 3
1 Lever for valve travel
1.1 Shaft
2 Pin
2.1 Nut
3 Sleeve
4 Zero adjustment screw
5 Mounting screw
6 Range spring
6.1 Bracket
7 Mounting screw
8 Measuring diaphragm
9 Diaphragm plate
9.1 Feeler pin
10 Nozzle block
10.1 Nozzle
10.2 Flapper
11 Cover plate
12 Booster
13 Xp restriction
14 Volume restriction Q
15 Hole for mounting screw
20 Plate
21 i/p converter unit
Arrangement of nozzle/flapper for
reverse <> operating direction
Travel

2 Attachment
To attach the positioner to valves with cast
yokes, mounting parts (order no.
1400-5745) are used. For valves with
rod-type yokes (pillars), the mounting kit (or-
der no. 1400-5745) and additionally the
mounting kit (order no. 1400-5342) are
necessary (see also accessories table on
page 20).
Since the positioner can be attached on ei-
ther side of the valve, the physical location
(left or right attachment) should be deter-
mined before actual attachment (see corre-
sponding Figs. 7 to 10 in section 4.1).
2.1 Attachment to valves with
cast yokes
1. Fasten the plate (20) to the stem connec-
tor clamps (22) of the valve using the
screws (21).
2. Unscrew the positioner cover, and secure
the device to the valve yoke using the
mounting screw (15). The O-ring in-
cluded in the mounting kit is not required
for this device. Make sure that the pin (2)
is routed inside the wire strap and there-
fore clamped against the plate (20).
8EB 8359-2 EN
Attachment
15 1 20 2 2.1 21 22 23
Fig. 4 · Attachment to valves with cast yokes (NAMUR rib)
Legend for Figs. 4 and 5
1 Lever
2 Pin
2.1 Nut
15 Mounting screw
20 Plate
21 Screw
22 Stem connector
23 Plug stem
24 Travel indicator
26 Clamping plate
27 Valve rods
28 Support

2.2 Attachment to valves with
rod-type yokes
1. Screw the plate (20), off-centered, to the
travel indicator (24) of the plug stem (23)
using the screws (21).
2. Place both the support (28) and the
clamping plate (26) on the rod (27) and
lightly fasten. Move the support until both
the center of the plate (20) and the sup-
port (28) are aligned at half the valve
travel.
3. Screw tight the support and clamping
plate.
4. Mount the positioner to the support using
the mounting screw (15). Make sure that
the pin (2) is led inside the wire strap
and therefore clamped against the plate
(20).
2.3 Cover of the positioner
housing
After attaching the positioner, make sure
that the vent plug on the cover of the
positioner housing points downwards after
the valve has been installed.
EB 8359-2 EN 9
Attachment
151282726202.12 212423
Fig. 5 · Attachment to valves with rod-type yokes

3 Connections
3.1 Electrical connections
DANGER!
Risk of electric shock and/or the
formation of an explosive atmo-
sphere!
–
For electrical installation, observe the rel-
evant electrotechnical regulations and
the accident prevention regulations that
apply in the country of use.
–
The following regulations apply to
mounting and installation in hazardous
areas: EN 60079-14: 2008 Explosive
atmospheres – Part 14: Electrical instal-
lations design, selection and erection (or
VDE 0165 Part 1).
NOTICE
–
Adhere to the terminal assignment!
Switching the assignment of the electrical
terminals may cause the explosion pro-
tection to become ineffective!
–
Do not loosen enameled screws in or on
the housing.
–
The maximum permissible values speci-
fied in the national EC type examination
certificates apply when interconnecting
intrinsically safe electrical equipment (U
i
or U
o
; I
i
or I
o
; P
i
or P
o
; C
i
or C
o
, and L
i
or
L
o
).
Selecting cables and wires:
Observe Clause 12 of EN 60079-14: 2008
when installing intrinsically safe circuits. The
Subclause 12.2.2.7 applies when running
multi-core cables containing more than one
intrinsically safe circuit.
In particular, the radial thickness of the con-
ductor insulation for common insulation ma-
terials, such as polyethylene, must have a
minimum radial thickness of 0.2 mm.
The diameter of an individual wire in a
fine-stranded conductor must not be smaller
than 0.1 mm. Protect the conductor ends
against splicing, e.g. by using wire-end fer-
rules.
When two separate cables are used for con-
nection, an additional cable gland can be
installed.
Seal cable entries left unused with plugs.
Devices used at ambient temperatures be-
low –20 °C must be fitted with metal cable
glands.
Equipment for use in zone 2/zone 22
In equipment operated with type of protec-
tion Ex nA II (non-sparking equipment) ac-
cording to EN 60097-15: 2003, circuits
may be connected, interrupted or switched
while energized only during installation,
maintenance or repair.
The wiring for the input signal is led using
cable glands to the terminals 11 (+) and 12
(–). The ground connection can be
connected inside or outside of the positioner
housing.
10 EB 8359-2 EN
Connections

The following accessories are available:
Cable gland M 20 x 1.5
Black Order no. 1400-6985
Blue Order no. 1400-6986
Adapter M 20 x 1.5 to ½ NPT:
Aluminum, powder-coated
Order no. 0310-2149
3.2 Pneumatic connections
The pneumatic connections are designed as
tapped holes with ¼ NPT or ISO 2228/1-
G ¼ thread. The conventional male connec-
tions for metal and copper pipes (or plastic
hoses) can be used.
Note:
The supply air must be dry and free of any
oil and dust. Always observe the mainte-
nance instructions applicable to the con-
nected pressure reducing stations. Blow out
air lines thoroughly before connecting them.
3.2.1 Pressure gauges
We recommend attaching pressure gauges
for the supply air and signal pressure in or-
der to monitor the positioner. The parts are
listed as accessories in the table on page
20.
3.2.2 Supply pressure
The required supply pressure is determined
by the bench range and the operating direc-
tion (fail-safe action) of the actuator. The
bench range is written on the nameplate as
spring range or signal pressure range de-
pending on the type of actuator. FA (actua-
tor stem extends) or FE (actuator stem re-
tracts) or a symbol indicates the operating
direction.
Actuator stem extends (FA)
Fail-safe position Valve CLOSED
(for globe and angle valves)
Required supply pressure =
Upper bench range value + 0.2 bar,
minimum 1.4 bar.
Actuator stem retracts (FE)
Fail-safe position Valve OPEN
(for globe and angle valves)
The required supply pressure for a
tight-closing valve is roughly estimated from
the maximum signal pressure pstmax:
pstmax = F + dp
A
2
4
××
×
pD [bar]
d = Seat diameter [cm]
Dp = Differential pressure across valve [bar]
A = Actuator diaphragm area [cm²]
F = Upper bench range of actuator [bar]
EB 8359-2 EN 11
Connections
Fig. 6 · Electrical connection
Input
control signal
(0)4 to 20 mA

In the absence of such specifications, pro-
ceed as follows:
Required supply pressure =
Upper bench range value + 1 bar
The positioner output pressure is led to the
top or bottom diaphragm case of the actua-
tor as shown in Figs. 7 to 10.
4 Operation
4.1 Combining positioner and
actuator
The arrangement of the actuator, input sig-
nal, operating direction and mounting loca-
tion is schematically represented in Figs. 7
to 10.
Each subsequent change such as reversal of
the control loop's operating direction or field
reversing the actuator version from direct
"Actuator stem extends" to reverse "Actuator
stem retracts" or vice versa also involves
changing the mounting location of the
positioner.
4.1.1 Determining/reversing the
operating direction
(Figs. 7 to 11)
When the input signal (reference variable w)
increases, the signal pressure pst can either
be increasing (direct operating direction <<)
or decreasing (reverse operating direction
<>). The same applies to a decreasing input
signal; the output pressure either decreases
(direct operating direction <<) or increases
(reverse operating direction <>). Symbols
are located on the flapper (10.2) which
identify the respective operating directions
(direct << or reverse <>).
Depending on the flapper position, the ad-
justed operating direction is marked with the
corresponding symbol. If the operating di-
rection of the required function does not
match the symbol or if the operating direc-
tion is to be changed, proceed as follows:
1. Remove both screws of the cover plate,
and lift off the nozzle block (10) along
with the cover plate.
2. Reinstall the nozzle block turned 180° to-
gether with the cover plate, and screw
tight.
Make sure that the nozzle block and flapper
are correctly located above or below the
feeler pin (9.1) as shown in Fig. 11.
If the operating direction is to be changed
after the initially determined arrangement of
positioner and actuator, note that the
positioner must be mounted in a different lo-
cation and the nozzle block must be turned.
Always consider the location of the lever (1)
and the plate (20), "lever on top of plate" or
reversed "plate on top of lever" as shown in
Figs. 7 to 10.
12 EB 8359-2 EN
Operation

EB 8359-2 EN 13
Operation
Fig. 11 · Position of nozzle block, cover plate removed
Actuator: Stem extends (FA)
Actuator: Stem retracts (FE)
1
20
pst
w
Fig. 7 · Operating direction << Left attachment
1
20
pst
w
Fig. 8 · Operating direction <> Right attachment
pst
w
Fig. 9 · Operating direction << Right attachment
pst
w
Fig. 10 · Operating direction <> Left attachment
Nozzle block
Feeler pin
Cover plate
Range spring
Marking Flapper
Operating direction increasing/increasing (direct <<)
feeler pin on top of flapper
Operating direction increasing/decreasing (reverse <>)
flapper on top of feeler pin
Lever (1) on top of plate (20) Plate (20) on top of lever (1)

4.2 Starting point and input
signal (reference variable)
The attached lever and the installed range
spring of the positioner are assigned to the
values of rated valve travel (mm) and the in-
put signal (% reference variable) as in the
table below.
In standard operation, the reference vari-
able span is 100 % = 16 mA. A smaller
span of, for example, 50 % = 8 mA is only
required for split-range operation (Fig. 13).
The span can be changed by exchanging
the range spring (section 4.4). On making
adjustments to the positioner, the travel must
be adapted to the input signal and vice
versa.
14 EB 8359-2 EN
Operation
Rated travel [mm] Min./max. travel [mm] Reference variable (input signal) Range spring
Standard travels for SAMSON valves with lever I (40 to 127 mm long)
15 7.5 to 15 100 %
50 %
1
2
30 14 to 32 100 %
50 %
2
3
60 30 to 70 100 % 3
Additional travel ranges with lever I and lever extension (40 to 200 mm long)
20 7.5 to 26 100 %
50 %
1
2
40 14 to 50 100 %
50 %
2
3
> 60 30 to 90 100 % 3
100%
0% 4 20mA
Fig. 12 · Standard operation
Reference variable
Input signal
Closed
Travel
Open
100%
0% 4 12 20mA
Fig. 13 · Split-range operation, two valves
operating in opposing directions
Open
Travel
Closed Valve 2 Valve 1
Dead band

With a 4 to 20 mA input signal, for exam-
ple, the valve must also move through the
entire range (0 to 100 % ). The starting point
then is 4 mA and the upper range value
20 mA.
In split-range operation, the controller output
signal used to control two control valves is
divided in such a way that these valves
move through their entire travel with half of
the input signal range (e.g. first valve set to
4 to 12 mA, second valve set to 12 to
20 mA). To prevent the two from overlap-
ping, a dead band of ±0.5 mA as in Fig. 13
must be taken into account.
The starting point (zero) is adjusted using
the zero adjustment screw (4), the reference
variable span and, hence, the upper range
value using the pin (2).
4.3 Setting the positioner at the
valve
4Connect an ammeter to the control signal
input at the terminals 11 (+) and 12 (–).
4Connect the supply air to the supply input
(supply 9).
4.3.1 Setting the air delivery
(volume restriction Q) and
proportional band XP
1. Close the volume restriction (14) as far
as the required speed of response al-
lows.
You can check the speed of response by
pressing the range spring (6) as far as it
will go.
2. Set the input signal to approximately 50
% of its range. Then, turn the zero adjust-
ment screw (4) until the valve is at ap-
proximately 50 % valve travel.
On setting the Xp restriction, observe the re-
lationship with the supply air pressure as in-
dicated in Fig. 14. The preset value of Xp
should read approximately 3 %.
3. Check the plug stem's tendency to oscil-
lation by pressing the range spring (6)
briefly as far as it will go.
Xp should be set to a value as small as
possible, however, without causing no-
ticeable overshoot.
Note:
Always determine the Xp setting prior to ad-
justing the starting point. Subsequent modifi-
cation displaces the zero point!
The zero can also be shifted by altering the
adjusted supply air pressure.
If necessary, check the zero adjustment un-
der operating conditions of the plant and,
re-adjust, if need be.
EB 8359-2 EN 15
Operation
Zul. Supply Alim.
Xp
[%]
5
4
3
2
1
0
6 bar 3 bar 1.4 bar
90° 0°180°270°
270°90°
180°
0°
360°
Fig. 14 · Setting the XP restriction

4.3.2 Setting actuator version
“Stem extends”
Note:
To ensure that the total closing force of the
actuator can be effective in the control valve,
the diaphragm chamber must be completely
vented at the lower range value of the refer-
ence variable (operating direction <<) and
at the upper range value (operating direc-
tion <>).
Therefore, set input signal to a slightly in-
creased starting point of 4.5 mA when the
operating direction is direct << and to a
slightly lowered starting point of 19.5 mA
when the operating direction is reverse <>.
This applies in particular to controllers and
control systems whose output signal is lim-
ited to a range of 4 to 20 mA.
Starting point (zero) e.g. 4.5 mA
1. Turn the zero adjustment screw (4) until
the plug stem just begins to move from
the resting position (observe plug stem
with travel indicator).
2. Reduce the input signal on the ammeter
and increase again slowly. Check
whether the plug stem starts moving at a
starting point of 4.5 mA and, if neces-
sary, correct.
Upper range value (span) e.g. 20 mA
3. After the starting point has been ad-
justed, increase the input signal. The plug
stem must be motionless at an upper
range value of exactly 20 mA and there-
fore already moved through 100 % of its
travel range (watch the travel indicator at
the valve!). If the upper range value is in-
correct, the pin (2) must be moved as fol-
lows in order to correct the signal:
4. Move pin to:
End of lever –> to increase travel
Pivot –> to reduce travel
Whenever you correct the input signal,
re-adjust zero afterwards. Subsequently,
check the upper range value.
Repeat until the two values match.
4.3.3 Setting actuator version
“Stem retracts”
Note:
For actuator version "Actuator stem re-
tracts", the diaphragm chamber must be
loaded with a pressure that is capable of
tightly closing the control valve, even with
prevailing upstream pressure in the plant.
This concerns an upper range value of the
input signal corresponding to 20 mA (direct
operating direction <<) or a lower range
value corresponding to 4 mA (reverse oper-
ating direction <>).
The required signal pressure is indicated on
the adhesive label on the positioner or is
roughly estimated as in section 3.2.2.
Starting point (zero) e.g. 20 mA
1. Adjust the input signal to a starting point
of 20 mA on the ammeter.
Turn the zero adjustment screw (4) until
the control valve just begins to move
from the initial position.
2. Increase the input signal and slowly re-
duce to a starting point of 20 mA again.
16 EB 8359-2 EN
Operation

Check if the valve begins to move at ex-
actly 20 mA.
Correct deviation using the zero adjust-
ment screw (4); turning it counterclock-
wise moves the control valve earlier from
its final position and clockwise later.
Upper range value (span) e.g. 4 mA
3. After adjusting the starting point, adjust
the input signal to an upper range value
of 4 mA using the ammeter. With an up-
per range value of exactly 4 mA, the
plug stem must be motionless and there-
fore already moved through 100 % of its
travel range (watch the travel indicator at
the valve!).
4. If the upper range value is incorrect, the
pin (2) must be moved to correct the sig-
nal.
Adjust 20 mA and turn the zero adjust-
ment screw (4) until the required signal
pressure is indicated on the pressure
gauge.
By way of substitution for a pressure
gauge, set 19.5 mA as the starting point.
4.4 Exchanging the range spring
If the range is to be altered or changed to
split-range operation, replace the range
spring as shown in Fig. as follows:
1. Remove screw (7) on the range spring.
Pull out hexagon socket screw (5) and
the lever together with shaft.
2. Exchange range spring. Slide lever with
shaft through sleeve (3), positioner hous-
ing and bracket (6.1).
3. Secure range spring with the screw (7).
4. Move bracket and shaft until the screw
(5) sits on the flattened part of the shaft.
Tighten screw (5). Allow for a play from
0.05 to 0.15 mm between the lever (1)
and the sleeve (3) as well as between the
range spring (6) and the positioner
housing.
EB 8359-2 EN 17
Operation

5 Converting an
electropneumatic into a
pneumatic positioner
The appropriate conversion kit allows the
electropneumatic positioner to be converted
into a Type 4765 Pneumatic Positioner.
Note: EB 8359-1 EN then applies for the
converted Type 4765 Pneumatic Positioner.
Required conversion kit for model index
.02. or lower
for G threaded connection
Order number 1400-6724
for NPT threaded connection
Order number 1400-6725
Required conversion kit for model index .03.
or higher
for G threaded connection
Order number 1400-6795
for NPT threaded connection
Order number 1400-6796
1. Undo mounting screws and lift the i/p
converter unit together with the printed
circuit board out of the positioner
housing.
2. Remove screw gland (1). Plug on hose
(5) and screw the connecting nipple (4)
of the conversion kit tightly on the
housing.
3. Insert sealing element (7) into connecting
plate (6) and screw tight in the housing.
18 EB 8359-2 EN
Converting an electropneumatic into a pneumatic positioner
1324576
38
Fig. 15 · Converting the positioner
4 Connecting nipple
5 Hose
6 Connecting plate
7 Sealing element
1 Screw gland
2 Printed circuit board
3 i/p module

4. Push the free end of the hose onto the
connecting plate (6).
6 Servicing explosion-protected
devices
If a part of the device on which the explo-
sion protection is based needs to be ser-
viced, the device must not be put back into
operation until a qualified inspector has as-
sessed it according to explosion protection
requirements, has issued an inspection cer-
tificate or given the device a mark of confor-
mity.
Inspection by a qualified inspector is not re-
quired if the manufacturer performs a rou-
tine test on the device prior to putting it back
into operation. The passing of the routine
test must be documented by attaching a
mark of conformity to the device. Replace
explosion-protected components only by
original, routine-tested components from the
manufacturer.
Devices that have already been operated
outside hazardous areas and are intended
for future use inside hazardous areas must
comply with the safety requirements placed
on serviced devices. Before being used in-
side hazardous areas, test the devices ac-
cording to the specifications for servicing
explosion-protected devices.
7 Maintenance, calibration and
work on equipment
The interconnection with intrinsically safe
circuits to check or calibrate the apparatus
must only be performed with intrinsically
safe current/voltage calibrators and mea-
suring instruments to rule out any damage to
components relevant for explosion protec-
tion.
The maximum values for intrinsically safe
circuits specified in the approvals must be
kept.
EB 8359-2 EN 19
Servicing explosion-protected devices

8 Accessories and mounting parts
20 EB 8359-2 EN
Accessories and mounting parts
Accessories – Mounting parts Order number
Range spring 1
Range spring 2
Range spring 3
Lever I
Lever extension
Pressure gauge attachment
Pressure gauge attachment, free of copper
1190-0736
1190-0737
1190-0738
1690-6469
1400-6716
1400-6950
1400-6951
Mounting kit for valves with cast yoke acc. to NAMUR
Mounting kit for valves with rod-type yokes acc. to NAMUR for 18 to 35 mm
rod diameters
1400-5745
1400-5745 and
1400-5342
Spare parts assortment with seals and diaphragms 1400-6792
Spare parts assortment with seals, diaphragms and pneumatic components
(for model index .02 or higher)
1042-0040
Conversion kit to upgrade to degree of protection IP 65
(refer to SAMSOMATIC print Z 900-7 for more details)
1790-7408