Samson 4785 Service manual

PROFIBUS Positioner
Type 3785
PA device profile version 3.0
Fig. 1 ⋅Type 3785
Mounting and
operating instructions
EB 8382 2 EN
Firmware R 1.42/K 2.11
Edition Jan ary 2003

Contents Page
Safety instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Firmware modifications . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Technical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Positioner versions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
1. Design and principle of operation . . . . . . . . . . . . . . . . . . . . . . 10
1.1 Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
1.2 Communication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
2. Attaching the positioner . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
2.1 Direct attachment to Type 3277 ctuator . . . . . . . . . . . . . . . . . . . 12
2.2 ttachment according to IEC 60534-6 . . . . . . . . . . . . . . . . . . . . 16
2.2.1 Mounting sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
2.2.2 Presetting the valve travel . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
2.3 ttachment to rotary actuators . . . . . . . . . . . . . . . . . . . . . . . . 20
2.3.1 Mounting the cam follower roll lever . . . . . . . . . . . . . . . . . . . . . 20
2.3.2 Mounting the intermediate piece . . . . . . . . . . . . . . . . . . . . . . . 20
2.3.3 ligning and mounting the cam disk . . . . . . . . . . . . . . . . . . . . . 22
2.3.4 Reversing amplifier for double-acting actuators . . . . . . . . . . . . . . . . 24
2.4 Fail-safe position of the actuator . . . . . . . . . . . . . . . . . . . . . . . 24
. Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
3.1 Pneumatic connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
3.1.1 Pressure gauge . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
3.1.2 Supply air pressure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
3.2 Electrical connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
3.2.1 Forced venting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
3.2.2 Limit switches . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
3.2.3 Establishing communication (bus address) . . . . . . . . . . . . . . . . . . . 30
3.2.4 Local interface (SSP) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
4. Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
4.1 LED controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
4.2 Write protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
4.3 ctivating/deactivating the forced venting function . . . . . . . . . . . . . . 33
Contents
2EB 8382-2 EN

4.4 Default settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
4.4.1 djusting mechanical zero . . . . . . . . . . . . . . . . . . . . . . . . . 34
4.4.2 Initialization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
4.5 djusting the inductive limit switches . . . . . . . . . . . . . . . . . . . . 36
5. Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
6. Servicing explosion-proof versions . . . . . . . . . . . . . . . . . . . . . 37
7. How to implement the PROFIBUS Master Class 1 . . . . . . . . . . . . . . 38
7.1 Device Database Files (GSD) . . . . . . . . . . . . . . . . . . . . . . . . 38
7.2 Data exchange . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
7.3 Parameter description . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
7.4 Status code of the measured variable . . . . . . . . . . . . . . . . . . . . 44
7.5 Operating modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
7.5.1 Start-up (warm start) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
7.5.2 Monitoring function FS FE_TIME, FS FE_TYPE, FS FE _V LUE . . . . . . . 47
8. List of parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
9. Messages and diagnosis . . . . . . . . . . . . . . . . . . . . . . . . . . 66
9.1 Diagnosis messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66
9.2 "CHECK_B CK" messages . . . . . . . . . . . . . . . . . . . . . . . . . 68
9.3 Initialization messages . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
Dimensional diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . 72
Certificates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73
Contents
EB 8382-2 EN 3

Safety instructions
The device may only be assembled, started up or operated by trained and ex-
perienced personnel amiliar with the product.
According to these mounting and operating instructions, trained personnel is
re erred to as individuals who are able to judge the work they are assigned to
and recognize possible dangers due to their specialized training, their knowl-
edge and experience as well as their knowledge o the applicable
standards.
Explosion-proo versions o this device may only be operated by personnel
who have undergone special training or instructions, or who are authorized to
work on explosion-proo devices in hazardous areas (also see section 6).
Any hazards which could be caused in the control valve by the process me-
dium, the operating pressure, the signal pressure or by moving parts are to be
prevented by means o the appropriate measures.
I inadmissible motions or orces are produced in the pneumatic actuator as a
result o the supply air pressure level, it must be restricted by means o a suit-
able pressure reducing station.
Proper shipping and appropriate storage are assumed.
Note! The device with a CE marking ul ils the requirements o the Directives
94/9/EC (ATEX) and 89/336/EEC (EMC).
The declaration o con ormity can be viewed and downloaded on the Internet at
http://www.samson.de.
4EB 8382-2 EN

Modifications in the positioner firmware compared to earlier version
Old New
Control R 1.23 R 1.31
Firmware adaption for new hardware version
Hardware version device index .01
Control R 1.31 R 1.4
ctuator type When the actuator type is set from "linear actuator" to "rotary
actautor", the following applies:
Initialization method ............Based on maximum range
Transmission code ...............S90
Nominal angle ....................90°
Final position for w <...........1 %
Final position for w >...........99 %
Rotat. angle range begins.....0°
Rotational angle range ends.90°
When the actuator type is set from "linear actuator" to "rotary
actautor", the following applies:
Attachment .........................Integral...............................According to NAMUR
Type of initialization.............Based on nominal range ......Based on nominal range
Mounting position................ rrow towards actuator ....... rrow away from actuator
Transmission code.................D1 ......................................
Pin position...................................................................
Rated travel..........................15 mm ................................15 mm
Final position for w < ............1 %.....................................1 %
Final position for w > ............125 %.................................125 %
Lower travel range value........0 mm ..................................0 mm
Upper travel range value.......15 mm ................................15 mm
Lever length...................................................................42 mm
Type of initialization When the initialization method is set from "maximum range" to
"nominal range", the following applies:
Final position for w < 1 % Final position for w > 125 %
When the initialization method is set from "maximum range" to
"nominal range", the following applies:
Final position for w < 1 % Final position for w > 99 %
Desired transit time
Open/Closed
The adjustment range of the desired transit times was limited to
75 seconds.
Initialization During initialization, the minimum control signals from 20 % to
80 % of the range of the manipulated variable are determined
and saved in the EEPROM.
Firmware modifications
EB 8382-2 EN 5

Proportional-action
coefficients
KP_Y1 and KP_Y2
The coefficients are adapted to the selected actuator type and
the measured transit times.
Control R 1.41 R 1.4.2
Correction in case of zero adjustment triggered via
communication.
Communication K 1.34 K 1.41
Firmware adaption for new hardware version
Hardware version device index .01
Communication K 1.41 K 1.51
The current status of control loop monitoring is indicated by
bit 7 of the CHECK_B CK parameter. Contrary to bit 13, bit 7
is automatically reset when no further error is detected by
control loop monitoring. The function of bit 13 remains
unchanged. Messages are only issued by bit 7 if control
firmware version R 1.41 or higher is used.
The message "Warm start" indicated by bit 11 of the
DI GNOSIS parameter is automatically reset after 10 sec.
In operating mode "Local override", bit 2 of the CHECK_B CK
parameter is set.
Communication K 1.51 K 1.60
In operating mode "Manual", the out value is preset by the
parameter OUT.
Communication K 1.60 K 2.00
This firmware version implements the PROFIBUS PA Profile .0,
Class B for control valves according to PROFIBUS P Profile for
Process Control Devices Version 3.0- ctuator.
The positioner can be connected to the TROVIS-VIEW
Configuration and Operator Interface via the serial interface for
adjustment and operation.
Firmware modifications
6EB 8382-2 EN

Communication K 2.00 K 2.10
When a zero point error or self-resetting control loop error
(transit time exceeded) is detected, or when the limit value for
the total valve travel is exceeded, the status of the parameters
RE DB CK or POS_D is set to
GOOD_M INTEN NCE_REQUIRED.
Firmware modifications
EB 8382-2 EN 7

Tec nical data
Positioner
Rated travel
Direct attachment to Type 3277
ttachment acc. to IEC 60534-6
(N MUR)
djustable
7.5 to 30 mm
7.5 to 120 mm
Or 30° to 120° for rotary actuators
Bus connection Fieldbus interface according to IEC 61158-2
Field unit according to FISCO (Fieldbus Intrinsically Safe COncept)
Permissible operating voltage 9 to 32 V DC

, supplied by bus connection
Static destruction limit 35 V
Maximum operating voltage 10 m
Current in case of fault 0 m
Supply air Supply air 1.4 to 6 bar (20 to 90 psi) ir quality according to ISO 8573-1:
Max. par ticle size and density: Class 2, Oil concentration: Class 3.
The pressure dew point must be 10 °C below the lowest ambient temperature
value to be expected
Signal pressure (output) 0 bar to supply air pressure
Characteristic, adjustable Linear, equal percentage, reverse equal percentage, freely programmable
Deviation from characteristic
≤1 %
Dead band
(based on rated travel/nom. angle)
djustable from 0.1 to 10.0 % , default 0.5 %
Resolution <0.05 % (internal measurement)
Transit time Up to 240 sec, separately adjustable for exhaust and supply air
Operating direction Reversible, adjustable using software
ir consumption Independent of supply air <90l

/h
ir supply ctuator filled: at
∆p = 6 bar 9.3 m

/h, at ∆p = 1.4 bar 3.5 m

/h
ctuator vented: at
∆p = 6 bar 15.5 m

/h, at ∆p = 1.4 bar 5.8 m

/h
Permissible ambient temperature 40 to 80 °C; the values of the EC Type Examination Certificate apply
additionally for explosion-proof devices
Effects Temperature: ≤0.15 %/10 K, auxiliary power: none,
Vibration: none up to 250 Hz and 4 g
Explosion protection II 2 G EEx ia IIC T6 according to TEX, see type examination certificate
Degree of protection IP 65 achieved by enclosed filter check valve
Electromagnetic compatibility Complies with requirements as in EN 50081/50082
Binar y input Internal power supply 5 V DC, R

= 100 kΩ
For signaling function, e.g. connection of a pressure switch
Forced venting,
to be activated via switch inside the
positioner
Input: 6 to 24 V DC, static destruction limit 45 V, R

approx. 6 kΩat 24 V DC
(depending on voltage), switching point 1- signal at
≥ 3V, 0- signal only at 0 V,
Kv value 0.17
8EB 8382-2 EN

Communication Data transfer according to PROFIBUS P Profile, Class B, Version 3.0 according to
DIN EN 50170 and DIN 19245 Part 4 (version 2.0 also available)
Local interface S MSON SSP inter face for configuration and start-up
Bus address djustable using software or microswitch, delivered as 126
Accessories
Inductive limit switches Two proximity switches SJ 2 SN for connection to switching amplifier according to
EN 50227
Materials
Body Die-cast aluminum, chromated and plastic-coated
External parts Stainless steel 1.4571 and 1.4301
Weight pprox. 1.3 kg

For the intrinsically safe version 3785-1..., the data given in the type examination certificate apply (see ppendix)
Versions
Positioner versions
Model 785 - XXXXX X
Explosion protection Without
II 2 G EEx ia IIC T6 acc. to TEX
With Ex ia CS /FM
0
1
ccessories Limit switches Without
2 inductive
0
22
Forced venting Without
With
0
12
P device profile Version 2.0
Version 3.0
0
1
Pneumatic
connections
NPT 1/4- 18
ISO 228/1- G1/4
1
2
Electric connections Cable gland M 20 x 1.5 with
shield, nickel-plated brass
Number: 1
Number: 2
1
2
EB 8382-2 EN 9

1. Design and principle of oper-
ation
The digital PROFIBUS P positioner is at-
tached to pneumatic control valves. It as-
signs the valve position (controlled variable)
to the control signal (reference variable).
The positioner compares the digital control
signal transmitted from the control equip-
ment to the travel of the control valve and
issues a pneumatic signal pressure (output
variable). To do so, a supply air pressure of
1.4 to 6 bar is required. The electric power
is supplied by the bus connection of the
PROFIBUS P segment in accordance with
IEC 61158-2 regulations.
The positioner consists of an inductive, fric-
tionless displacement sensor system and an
electrically controlled valve block with two
on-off valves, as well as the electronics in-
cluding the two microcontrollers to edit the
control algorithm and manage PROFIBUS
communication.
When a system deviation occurs while com-
paring set point and actual value, the micro-
controller returns binary pulse-pause-modu-
lated signals which are used to control two
on-off valves with subsequent boosters. One
valve controls the exhaust air, the other the
supply air.
The supply air valve (3) connects the supply
air (7, supply air pressure 1.4 to 6 bar) and
the actuator (filling). The exhaust air
valve (4) connects the actuator and the at-
mosphere (venting). These on-off valves can
either have the switching states continuously
open or continuously closed, or they can
generate single pulses of variable width.
Controlling the two valves causes the actua-
tor of the control valve to move the plug
stem to a position corresponding to the ref-
erence variable. If there is no system devia-
tion, both the exhaust and supply air valves
are closed.
By default, the positioner is equipped with a
binary input for floating contacts, which
serves to signalize the switching state of an
additional field device via PROFIBUS.
The write protection switch in the hinged
cover (located near the bus address adjust-
ment) prevents that positioner settings are
overwritten via PROFIBUS communication
on activation.
Positioner with forced venting function:
The positioner is controlled by a 6 to 24 V
signal, causing the signal pressure to be ap-
plied to the actuator. When this voltage sig-
nal decreases, the signal pressure is shut off
and the actuator is vented. dditionally, the
control valve is moved to its fail-safe posi-
tion by the integrated springs.
ll positioners are equipped with the forced
venting function, which can be activated
and deactivated using a switch (also see sec-
tion 4.3).
1.1 Options
The standard positioner version can be sup-
plemented with limit switches. Two
proximity switches suitable for fail-safe cir-
cuits can be used to signalize the valves
final positions.
1.2 Communication
The positioner is completely controlled via
digital signal transmission according to
PROFIBUS P Profile Class B based on
DIN EN 50170 and DIN 19245 Part 4.
Data is transmitted as bit synchronous cur-
rent modulation with a transfer rate
10 EB 8382-2 EN
Design and principle of operation