Baker Hughes Masoneilan 496 Series User manual

Masoneilan™
496 Series
Position Transmitter and Limit Switch
ATEX Instruction Manual (Rev.D)
Baker Hughes Data Classification: Public

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THESE INSTRUCTIONS PROVIDE THE CUSTOMER/OPERATOR WITH IMPORTANT
PROJECT-SPECIFIC REFERENCE INFORMATION IN ADDITION TO THE
CUSTOMER/OPERATOR’S NORMAL OPERATION AND MAINTENANCE PROCEDURES.
SINCE OPERATION AND MAINTENANCE PHILOSOPHIES VARY, BAKER HUGHES
COMPANY (AND ITS SUBSIDIARIES AND AFFILIATES) DOES NOT ATTEMPT TO
DICTATE SPECIFIC PROCEDURES, BUT TO PROVIDE BASIC LIMITATIONS AND
REQUIREMENTS CREATED BY THE TYPE OF EQUIPMENT PROVIDED.
THESE INSTRUCTIONS ASSUME THAT OPERATORS ALREADY HAVE A GENERAL
UNDERSTANDING OF THE REQUIREMENTS FOR SAFE OPERATION OF MECHANICAL
AND ELECTRICAL EQUIPMENT IN POTENTIALLY HAZARDOUS ENVIRONMENTS.
THEREFORE, THESE INSTRUCTIONS SHOULD BE INTERPRETED AND APPLIED IN
CONJUNCTION WITH THE SAFETY RULES AND REGULATIONS APPLICABLE AT THE
SITE AND THE PARTICULAR REQUIREMENTS FOR OPERATION OF OTHER
EQUIPMENT AT THE SITE.
THESE INSTRUCTIONS DO NOT PURPORT TO COVER ALL DETAILS OR VARIATIONS
IN EQUIPMENT NOR TO PROVIDE FOR EVERY POSSIBLE CONTINGENCY TO BE MET
IN CONNECTION WITH INSTALLATION, OPERATION OR MAINTENANCE. SHOULD
FURTHER INFORMATION BE DESIRED OR SHOULD PARTICULAR PROBLEMS ARISE
WHICH ARE NOT COVERED SUFFICIENTLY FOR THE CUSTOMER/OPERATOR'S
PURPOSES THE MATTER SHOULD BE REFERRED TO BAKER HUGHES.
THE RIGHTS, OBLIGATIONS AND LIABILITIES OF BAKER HUGHES AND THE
CUSTOMER/OPERATOR ARE STRICTLY LIMITED TO THOSE EXPRESSLY PROVIDED
IN THE CONTRACT RELATING TO THE SUPPLY OF THE EQUIPMENT. NO ADDITIONAL
REPRESENTATIONS OR WARRANTIES BY BAKER HUGHES REGARDING THE
EQUIPMENT OR ITS USE ARE GIVEN OR IMPLIED BY THE ISSUE OF THESE
INSTRUCTIONS.
THESE INSTRUCTIONS ARE FURNISHED TO THE CUSTOMER/OPERATOR SOLELY
TO ASSIST IN THE INSTALLATION, TESTING, OPERATION, AND/OR MAINTENANCE
OF THE EQUIPMENT DESCRIBED. THIS DOCUMENT SHALL NOT BE REPRODUCED IN
WHOLE OR IN PART WITHOUT THE WRITTEN APPROVAL OF BAKER HUGHES.

© 2020 Baker Hughes Company. All rights reserved. Masoneilan 496 Series Position Transmitter ATEX Instruction Manual | 3
Conversion Table
All the USCS values are converted to
metric values using the following conversion factors:
USCS Unit
Conversion Factor
Metric Unit
in.
25.4
mm
lb.
0.4535924
kg
in2
6.4516
cm2
ft3/min
0.02831685
m3/min
gal/min
3.785412
L/min
lb/hr
0.4535924
kg/hr
psig
0.06894757
barg
ft lb
1.3558181
Nm
°F
5/9 (°F-
32)
°C
Note: Multiply USCS value with conversion factor to get metric value.
NOTICE!
For valve configurations not listed in this
manual, please contact your local MARC™
(Masoneilan Authorised Repair Center) or
Baker Hughes sales office for assistance.

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Contents
1. Instrument Operation.................................................................................. 6
2. Numbering System..................................................................................... 6
3. Technical Specification ............................................................................................7
4. ATEX Intrinsic Safety Marking and Electrical Safety Parameters .........................8
5. ATEX Flameproof Marking and Electrical Safety Parameters .............................10
6. Position Transmitter 496-8../. Electrical data.........................................................11
7. Electrical Connection, Installation and Start-up ...................................................12
8. Calibration.................................................................................................................15
9. Maintenance .............................................................................................................21
10. Special Conditions of Work.....................................................................................21
11. Special Conditions of Use ......................................................................................22
Annex I –Intrinsic Safety Temperatures .........................................................................24
Annex II –Flameproof Temperatures...............................................................................26
Annex III –Cable Gland Accessories Mounting..............................................................28
Annex IV - Switch Configurations ....................................................................................29

© 2020 Baker Hughes Company. All rights reserved. Masoneilan 496 Series Position Transmitter ATEX Instruction Manual | 5
Warning
BEFORE installing, using or carrying out any
maintenance tasks associated with this
instrument, READ THE INSTRUCTIONS
CAREFULLY.
These instruments comply with the essential
safety requirements of the European Directive
ATEX 2014/34/EU. It is certified to be used in
Gas or Dust explosive atmospheres, groups
IIA, IIB, IIC and IIIC:
•Category II 1 GD, II 1 G or II 2 G –zones 0,
1, 2, 20, 21 and 22 for the protection mode
“ia”
•Category II 2GD –zones 1, 2, 21 an d 22 for
the protection mode “db”and “tb”
They also comply with the essential safety
requirements of the European Directive EMC
2014/30/EU as amended, for use within an
industrial environment.
Products certified as explosion proof
equipment MUST BE:
a) Installed, put into service, used and maintained
in compliance with European and/or national
and local regulations and in accordance with
the recommendations contained in the relevant
standards concerning potentially explosive
atmospheres.
b) Used only in situations those comply with the
certification conditions shown in this document
and after verification of their compatibility with
the zone of intended use and the permitted
maximum ambient temperature.
c) Installed, put into service and maintained by
qualified and competent professionals who
have undergone suitable training for
instrumentation used in areas with potentially
explosive atmosphere. Such trainings are not
supported by Baker Hughes.
It is the end user’s responsibility to:
•Verify material compatibility with the
application
•Ensure proper use of fall protection when
working at heights, per Safe Site Work
Practices
•Ensure use of proper Personal Protective
Equipment
•Take the appropriate actions to ensure that
site personnel who are performing
installation, commissioning and
maintenance have been trained in proper
site procedures for working with and
around equipment, per Safe Site Work
Practices
Baker Hughes reserves the right to disconti-
nue manufacture of any product or change
product materials, design, or specifications
without notice.
Under certain operating conditions, the use of
damaged instruments could cause a degradation
of the performances of the system which may
lead to personal injury or death.
Use only Baker Hughes Masoneilan replacement
parts to ensure that the products comply with the
essential safety requirements of the European
Directives mentioned above.

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Protection
55. Weatherproof
57. Explosionproof and dust
and water tight
58.Intrinsically safe and dust
and water tight
Additional Function
1. One mechanical switch single
pole double throw
2. Two mechanical switches
single pole double throw
4. One proximity switch
5. Two proximity switches
6. One mechanical switch double
pole double throw
7. Two mechanical switches
double pole double throw
1. Instrument Operation
1.1 The 496-.58 and 496-.57 position
limit switch
Allow switching 1 or 2 electrical circuits. This
function is provided by 1 or 2 micro- switch(es)
or 1 or 2 proximity switch(es). This device can
be mounted on both rotary and reciprocating
valves.
1.2 The 496-857 and 496-857/. and
496-858 or 496-858/. position
transmitter
The 496 Series instrument is a non-contact
opto- electronic positioner transmitter which
provides a 4-20mA analog output signal
proportional to the valve position. This device
can be both mounted on rotary and
reciprocating valves.
The opto-electronic sensor has the same
function than a standard potentiometer and its
output voltage is proportional to the rotation of its
axis.
An electronic circuit amplifies this voltage to a
4-20 mA signal proportional to the angle of
rotation. This equipment has many advantages:
•non-electrical noise typical of potentiometer
with cursor
•frictionless
•unlimited life
•non-sensitive to vibration and electrical noise
•very low operating torque: 0.02 N.m
Optionally, 496-8xx/x apparatus can be used
with additional functions as 1 or 2 micro-
switch(es) or 1 or 2 proximity switch(es). This is
also possible for type 496-1xx/x and type
496-2xx/x with the same type of switch.
2. Numbering System
496 - _ _ _ / _
Type
1. One mechanical switch single
pole double throw
2. Two mechanical switches
single pole double throw
4. One proximity switch
5. Two proximity switches
6. One mechanical switch double
pole double throw
7. Two mechanical switches
double pole double throw
8. Optoelectronic position
transmitter

© 2020 Baker Hughes Company. All rights reserved. Masoneilan 496 Series Position Transmitter ATEX Instruction Manual | 7
3. Technical Specification
Internal components for limit switch and position transmitter are mounted inside an IP66/IP67
enclosure.
Performances of position transmitter type 496-857 or 496-857/. and 496-858 or 496-858/.
• Output signal: 4-20 mA (2 wires)
• Acceptable span on the command axis: from 25° to 90° for rotary or reciprocating valves
• Rotation: clockwise or counterclockwise
• Linearity: ≤ ± 0.5% for a rotary angle of 25° to 90° (typically ± 0.3% for a rotary angle ≥ 60°)
• Hysteresis: ≤ 0.1%
• Dead band: ≤ 0.1%
• Repeatability: ≤ 0.1%
• Total drift in temperature: 0.02 %/°C or 200 ppm/°C (zero and span range)
• Operating temperature range: -40°C to +80°C
Electrical characteristics and temperature range of the position transmitter with micro-
switch(es) or proximity switch(es) are given in the following sections.

8| Baker Hughes © 2020 Baker Hughes Company. All rights reserved.
4. ATEX Intrinsic Safety Marking and Electrical
Safety Parameters
4.1 Marking
The marking is on the serial plate stamped on the
496 cover (rep 14).
•Name and address of the manufacturer:
Dresser Produits Industriels S.A.S.
14110 CONDE SUR NOIREAU - FRANCE
•Type designation:
–496-858 for position transmitter
–496-858/• for position transmitter with
additional function(s)
the “•” can take the values 1, 2, 4, 5
–496-•58 for position switches
the “•” can take the values 1, 2, 4, 5
–496-158/• and 496-258/• for position switches
with additional function(s)
the "•" can take the values 1, 2
•Basic and complementary marking:
–Position transmitter alone or Position
transmitter equipped with microswitch(es)
(additional function):
Types: 496-858 or 496-858/1 or 496-858/2
II 1 GD
Ex ia IIC T.* Ga Tamb = -..°C à +..°C*
Ex ia IIIC T..°C* Da
–Positiontransmitter equipped with proximity
detector(s) (additional function):
Types: 496-858/4 or 496-858/5
II 1G
Ex ia IIC T.* Ga Tamb = -..°C à +..°C*
or
II 2G
Ex ia IIC T.* Gb Tamb = -..°C à +..°C*
–Position contactor alone equipped with
microswitch(es):
Types: 496-158 or 496-258 or 496-158/•or
496-258/•
II 1 GD
Ex ia IIC T.* Ga Tamb = -..°C à +..°C*
Ex ia IIIC T..°C* Da
–Position contactor alone equipped with
proximity detectors:
Types: 496-458 or 496-558
II 1G
Ex ia IIC T.* Ga Tamb = -..°C à +..°C*
or
II 2G
Ex ia IIC T.* Gb Tamb = -..°C à +..°C *
*Ambient temperatures ranges and surface temperatures for
the temperature classifications T6, T5 and T4 are given in
Annex I with:
•Tables 1, 2 and 3 for the transmitter alone, the
mechanical switch(es) alone and the proximity
switch(es) alone.
•Tables 4 and 5 for the transmitter with mechanical
switch(es) and for the transmitter with proximity
switch(es).
•Serial number
•Year of manufacturing
•Number of notified body ••••
•EC-Type examination certificate number
Warning:
AVERTISSEMENT : DANGER POTENTIEL DE
CHARGES ELECTROSTATIQUES –VOIR
INSTRUCTIONS
WARNING: POTENTIAL DANGER OF
ELECTROSTATIC CHARGES. SEE
INSTRUCTIONS
4.2 Electrical safety parameters
4.2.1 Type 496-•58
4.2.1.1 Option with 1 or 2 Micro-Switch(es)
•Type identification is: 496-158 and 496-258
•Mechanical switch(es): type BZ-2R72-A2,
manufacturer: HONEYWELL
•They are supplied by a certified power source
for explosible atmospheres group IIC with the
maximal characteristics:
–Constant power supply: Ui= 30V, Ii = 0.5A,
Ci = 0F and Li = 0H
–Alternative power supply: Ui= 90V, Ii = 1.4A,
Ci = 0F and Li = 0H
•The wiring connection is done directly on
mechanical switch(es).
4.2.1.2Option with 1 or 2 Proximity Switch(es)
•Type identification is: 496-458 and 496-558
•These detectors from PEPPERL & FUCHS are
defined as:
–II 1G Ex ia IIC T6 Ga
–II 2G Ex ia IIC T6 Gb
•EC type examination certificate:
–PTB 00 ATEX 2048 X (II1G, II2G)
–PTB 00 ATEX 2049 X (II1G, II2G)

© 2020 Baker Hughes Company. All rights reserved. Masoneilan 496 Series Position Transmitter ATEX Instruction Manual | 9
4. ATEX Intrinsic Safety Marking and Electrical
Safety Parameters (Cont’d)
•They are supplied by a certified power source* for
explosible atmospheres with the maximal
characteristics:
Ui = 16V ; Ii = 0.052A ; Pi = 0.169W.
* The power source (Control circuit) must be one
manufactured by Pepperl & Fuchs below:
WE 77/EX 1 or WE 77/EX 2
•The wiring connection is done on one or two
terminal connector type:
MK 3 ; 2.5mm2 ; 380 volts ; manufacturer:
WEIDMULLER or equivalent product.
4.2.1.3 Maximum Characteristics
Variation Ui Ii Ci
(V) (A) (nF)
Li Pi
(μH) (W)
With
Micro-
switch
DC Source
30
0.5
0
0
–
AC Source
Peak Value
90
1.4
0
0
-
With Proximity Switch
16
0.052
120
200
0.169
4.2.2 Types 496-858 and 496-858/. :
4.2.2.1 Type 496-858:
The position transmitter is connected to a certified
linear power supply for explosible atmospheres Group
IIC, IIB or IIA and its output circuit is recognized for an
intrinsic safety used per EN 60079-11.
Maximum characteristics:
Ui (V) Ii (A)
Ci (nF)
Li (μH)
Pi (W)
28
0.11
30
0
0.77
4.2.2.2Type 496-858/. :
The additional functions of position transmitter are
identical to type 496-•58

10 | Baker Hughes © 2020 Baker Hughes Company. All rights reserved.
Type Min Voltage Max Voltage
496-157 or
496-257 or
496-657 or
496-757
-
220V
(direct current) or
250V
(alternative current)
496-457 or
496-557
Pepperl &
Fuchs
-
16V
(direct current)
496-457 or
496-557
Télémécanique
-
58V
(direct current)
496-857/•
9.0V
(direct current)
36V
(direct current)
5. ATEX Flameproof Marking and Electrical Safety
Parameters
5.1 Marking
The marking is on the serial plate stamped on the
496 cover (rep 14).
•Name and address of the manufacturer
Dresser Produits Industriels S.A.S.
14110 CONDE SUR NOIREAU –FRANCE
•Type designation:
–496-857 for position transmitter
–496-857/• for position transmitter with
additional function(s)
The • can be replaced by 1, 2, 4, 5, 6, 7
–496-•57 for position switches
The • can be replaced by 1, 2, 4, 5, 6, 7
–496-157/• and 496-257/• for position switches
with additional function(s)
The • can be replaced by 1, 2
•the specific marking: II 2 GD
•the complementary marking:
For position switch(es) 496-•57 and 496-•57/•
and position transmitter with or without additional
function(s) 496-857 and 496-857/•
–Ex db IIC T6 Gb Ta –55°C, +75°C (*)
Ex tb IIIC T85°C Db IP66/IP67
–Ex d IIC T5 Gb Ta –55°C, +85°C (*)
Ex tb IIIC T100°C Db IP66/IP67
(*) Ambient temperatures ranges and surface
temperatures for the temperature classifications T6, T5
and T4 are given in Annex II with the different possible
combinations allowed.
•Serial number
•Year of manufacturing
•Number of notified body ••••
•EC-Type examination certificate number
Warning
AVERTISSEMENT : NE PAS OUVRIR SOUS TENSION
WARNING : DO NOT OPEN WHEN ENERGIZED
Warning
AVERTISSEMENT : DANGER POTENTIEL DE
CHARGES ELECTROSTATIQUES –VOIR
INSTRUCTIONS
WARNING: POTENTIAL DANGER OF ELECTROSTATIC
CHARGES. SEE INSTRUCTIONS
WARNING
AVERTISSEMENT : NE PAS OUVRIR SI UNE ATMOSPHERE
EXPLOSIVE GAZEUSE EST PRESENTE
WARNING: DO NOT OPEN WHEN AN EXPLOSIVE GAS
ATMOSPHERE IS PRESENT
•T cable:
Mandatory mention when the ambient temperature is
higher than 70°C.
T ambient T cable
70°C
75°C
75°C
80°C
80°C
85°C
85°C
90°C
5.2 Electrical safety parameter
•Maximum dispersed power = 5W
•Voltage supply allowable:

© 2020 Baker Hughes Company. All rights reserved. Masoneilan 496 Series Position Transmitter ATEX Instruction Manual | 11
6. Position Transmitter 496-8../. Electrical data
• Power supply:
Voltage Supply U (V)
Mini
Maxi
Flameproof
9.0V
36V
Intrinsic Safety
9.0V
28V
• Lightning protection (in standard): 1500W 10/1000µs
• Output current 4-20mA (two wires) Zc
• Zero range adjustment: ±0.5mA Supply
Voltage
• Span range adjustment: ±2.5mA
• Protected against polarity inversion
Supply Voltage
(
V
)
–9.0
(
V
)
• Maximum load Zc
(Ω)
=
This means for 20mA:
Imaxi
(
A
)
Zc = 950 Ohm max with for an intrinsically safe loop
and
Zc = 1350 Ohm for Flameproof.

12 | Baker Hughes © 2020 Baker Hughes Company. All rights reserved.
7. Electrical Connection, Installation and Start-up
•Comply with current national and local regulations for electrical installation work.
•Must be installed and put into service in conformance with EN 60079-14 and/or national and local
regulations applicable for explosible atmospheres.
•Before carrying out any work on the device, power off the instrument or make sure that the local
conditions in the potentially explosive atmosphere permit –the safe opening of the cover.
•Connect the wires to the instrument terminals, taking care of complying with polarities and
maximum voltage allowed.
•Before power up or after doing any work on the device always check the cover (12) is fully
screwed, O-ring (10) is free of any damage and security screw (9) is well locked.
•Check the earth terminals are well connected.
Note: Before installation, check that the device is undamaged. In the event of damage, inform the
Manufacturer whose address is shown on the serial plate.
7.1 Conduit entry in flameproof application
The connections can be done with different variations taking into account approved manufacturer and
requested approvals:
•A cable entry of a certified type II 2 GD Ex d IIC / Ex tb IIIC can be mounted directly on the single
¾" NPT (ANSI/ ASME B1.20.1) housing conduit connection.
•Adaptor or reducer if ATEX apparatus certified or IECEx (type Cooper CAPRI CODEC)
•For multiple cable entries (3 maximum), the adaptor Y237 “Masoneilan” can be used for ATEX
application only.
–If one Y237 input is not used, the conduit will be closed by a plug if ATEX apparatus certified
(type Cooper CAPRI CODEC)
–If two Y237 inputs are not used, the Y237 must be suppresse d .
•The cable entry with or without its adaptor/reducer and the Y237 with its cable entry must be installed
in conformance with Annex III.

© 2020 Baker Hughes Company. All rights reserved. Masoneilan 496 Series Position Transmitter ATEX Instruction Manual | 13
7. Electrical Connection, Installation and Start-up
(Cont’d)
7.2 Electrical connection for type
496-•57 or 496-•57/•and
496-•58 or 496-•58/•
• The electrical cables are connected either
directly on to the micro switch(es) or to the
proximity switch(es) terminal block.
• Connect the device to the earth using the earth
connections provided inside and outside the
housing of the device.
• Basic rule for wiring:
–Must be used in addition to local
regulation for electrical installation
–Connector slot approval:
–Insulation must be free of any damage along
the wires inside the housing
–Tightening must be sufficient to bring
constant contact in time without being
excessive to cut or damage connection.
7.3 Electrical connection for type
496-857 or 496-857/•and
496-858 or 496-858/•
Connect the electrical cables to the position
transmitter terminal block located on the printed
circuit board. Respect the polarities + and –and the
maximum voltage allowed.
When a position transmitter is provided with an
additional function, the electrical cables are
connected either directly on to the micro switch(es)
or to the proximity switch(es) terminal block.
Connect the device to the earth using the earth
connections provided inside the housing and on
the outside of the device.
• Basic rule for wiring:
–Must be used in addition to local
regulation for electrical installation
–Connector slot approval:
–Insulation must be free of any damage along
the wires inside the housing
–Tightening must be sufficient to bring
constant contact in time without being
excessive to cut or damage connection.

14 | Baker Hughes © 2020 Baker Hughes Company. All rights reserved.
7. Electrical Connection, Installation and Start-up
(Cont’d)
7.4 Installation and start-up
7.4.1 Installation
Flameproof instrument may be installed in gas
and dust explosive atmosphere of groups IIA, IIB,
IIC and IIIC for the zones 1, 2, 21 and 22 with
“db”and “tb” protection mode.
Intrinsically safe instrument may be installed in
gas and dust explosive atmosphere of groups
IIA, IIB,
IIC and IIIC for zones 0, 1, 2, 20, 21 and 22 with “ia”
protection mode.
Note:
It is under the user responsibility to check the installation against Intrinsic safety rules taking into
account entity parameters of all devices in the loop in addition of temporary one like
measurement devices.
7.4.2 Start-up
–Before power up or after doing any work on the device always check the cover (12) is fully
screwed, O-ring (10) is free of any damage and security screw (9) is well locked.
–Check that the cable gland is certified for the intended use and that the electrical data are
suitable for the operating zone.
Before start-up, proceed, if required, with instrument calibration as per §8 and/or ensure that all the
safety instructions in the preceding paragraphs have been strictly followed.

© 2020 Baker Hughes Company. All rights reserved. Masoneilan 496 Series Position Transmitter ATEX Instruction Manual | 15
8. Calibration
Before power up the device to proceed with
calibration carefully read the following safety
warnings.
–Comply with current national and local
regulations for electrical installation
work.
–Must be installed and put into service in
conformance with EN 60079-14 and / or
national and local regulations applicable
for explosible atmospheres.
–Before carrying out any work on the
device, power off the instrument or
make sure
that the local conditions in the
potentially explosive atmosphere
permit- the safe opening of the cover.
–Connect the wires to the instrument’s
terminals, taking care of complying
with polarities and maximum voltage
allowed.
–Before power up or after doing any work
on the device always check the cover (12)
is fully screwed, O-ring (10) is free of any
damage and security screw (9) is well
locked.
8.1 Calibration of rotary limit switch
496-157, 496-257, 496-158 and
496-258
•The concave portion of the lever (5) must be
strictly concentric to the cam (13) when the
micro-switch is actuated.
•This is an important caution to make sure the lever is
properly depressed when not actuated.
•If not, loosen the screws (3 & 17) and slightly move
the lever upwards or downwards. Tighten the screws.
•Slightly loosen the cam locking screw (1) using a
3/32” socket hex head wrench.
•Move the plug stem to the position required to actuate
the switch.
•It is important to note that the cam operating the right
hand micro-switch must actuate the lever (5) at the
end of the counterclockwise rotation. (See detail figure
below).
•This makes sure the screw (2) has free the lever (5)
when the valve is throttling. The remaining concave
portion only ensures micro-switch actuation in case of
over travel. Conversely, the cam operating the left
hand micro-switch must actuate the lever (5) at the
end of the clockwise rotation. (See front view below).
•To meet the above requirement when only one micro-
switch is provided (type 496-158) it may be necessary
to change the location of the micro-switch.
•Rotate the cam (13) until the micro-switch is actuated.
Lock the cam (13) tightening the screw (1).
•Fine tune adjustment with screw (2). Use a 1/16”
socket hex head wrench. The screw (2) must come
out the cam enough to properly depress the lever (5).
•Strictly follow safety instructions under §7.4
before putting into service.

16 | Baker Hughes © 2020 Baker Hughes Company. All rights reserved.
8. Calibration (Cont’d)
1 6 9 10 11 12 8 13
A
8
2
13
3
4 3
17
7
15
5
14
18
5
16
B
Parts List
Rep.
Designation
Rep.
Designation
Rep.
Designation
1
Adjusting screw
8
Snap ring
2
Adjusting screw
9
Safety screw
16
Insulating
3
Screw (1 micro switch)
10 (1)
Oring
17
Screw (second micro switch)
4
Micro switch
11
Axis
18
Washer
5
Lever
12
Cover
19 (2)
Spacer (Not shown)
6
Housing
13
Cam
A
Contact point for the left micro switch
7 (1)
O ring
14
Serial plate
B
Contact point for the right micro switch
(1) Recommended spare parts
(2) Only for 496-2 model

© 2020 Baker Hughes Company. All rights reserved. Masoneilan 496 Series Position Transmitter ATEX Instruction Manual | 17
Rep.
Designation
Rep.
Designation
33
Arm
34
Proximity switch
8.2 Calibration of rotary limit switch
496-.57 and 496-.58 equipped
with proximity switch(es)
8.2.1. Type 496-457 and 496-458
• Actuate the valve to the desired triggering position
and check the sense of rotation when the arm
leaves the proximity sensor.
• The figure below shows the location of the
proximity sensor and of the arm when triggering
as a function of the sense of rotation.
• Slowly move the arm towards the proximity
sensor until it triggers. Triggering occurs when
the arm overlaps approximately 1/3 of the
proximity switch.
• Strictly follow safety instructions under §7.4
before putting into service.
34 34
33
8.2.2. Type 496-557 and 496-558
During adjustment make sure that the proximity
switch with the red spot is triggered by the arm
with the red spot.
• Adjustment of the first proximity switch
–The first switch is adjusted at the beginning of
the stroke.
–Check what will be the sense of rotation when
the valve is actuated. Figure (b, c) below shows
the proximity sensor and the arm assigned to
the first triggering point for a given the sense of
rotation.
–Slowly move the arm towards the proximity
switch
until it triggers.
• Adjustment of the second proximity switch
–The second switch is adjusted at the end of the
actuator stroke.
–Immobilize the first arm previously adjusted
and slowly move the second arm towards the
second proximity sensor until it triggers.
–Make sure the first proximity switch is still
correctly adjusted.
• Strictly follow safety instructions under §7.4
before putting into service.
a
A
B
b B c
Rep.
Designation
Rep.
Designation
A
Red spot
B
First triggering point

18 | Baker Hughes © 2020 Baker Hughes Company. All rights reserved.
8. Calibration (Cont’d)
8.2.3. Air-gap adjustment
Air-gap between the proximity switch and the arm is
factory adjusted. If new adjustment is required
proceed as follows:
• Loosen the proximity sensor nut (37A), located on
the front of the bracket (36).
• Unscrew a few turns the locknut (37B) located on
the back of the bracket.
• Position the arm above the proximity sensor
and push the shaft end (11) towards the
outside of the housing so as to eliminate the
longitudinal play.
• Hold in position the proximity sensor and screw the
nut (37A). Adjust air gap to 0,3 mm using a shim
• Tighten the lock nut (37B).
6 9 10 11 12 8 30 37A
8
31
32
33
3 36
7 15
25 14
3
24
34 37B 19
Parts List
Rep.
Designation
Rep.
Designation
Rep.
Designation
3
Screw
12
Cover
31
Snap ring
6
Housing
14
Serial plate
32
Washer
7 (1)
O-ring
33
Arm
8
Snap ring
19
Spacer
34
Proximity sensor
9
Safety screw
24
Terminal block
35 (2)
Spacer (Not shown)
10 (1)
O-ring
25
Terminal block
36
Sensor bracket
11
Axis
30
Spacer
37
Nut
(1) Recommended spare parts (2) Only for 496-4 model

© 2020 Baker Hughes Company. All rights reserved. Masoneilan 496 Series Position Transmitter ATEX Instruction Manual | 19
Masoneilan
8. Calibration (Cont’d)
8.3 Calibration of position
transmitter 496-858 or 496-858/•and
496-857 or 496-857/•
• Action
The action sense of the valve (open or closed
valve, compared to the 4 - 20 mA of the loop
signal), determines the position of the connector
3 points
of the optoelectronic sensor on one of the
two connectors of electronic circuit A or B.
The operation rule is: for a clockwise rotation
of the pinion of the control shaft (view cover
side),
the output current increases (4→20 mA) when the
connector of the optoelectronic sensor is
connected in A and decreases when connected in
B.
A B
C
Z S
-
PN:
+
• Linkage adjustment
When mounted on reciprocating valves, adjust the
turnbuckle to get the instrument lever
perpendicular to the plug stem at mid-travel.
• Position transmitter adjustment
–Position the connector 3 points on connector A
or B in function of the chosen action.
–Preset mid travel the zero adjustment (Z)
if necessary*.
–Preset mid travel the span adjustment (S) if
necessary**.
–Configure the switch C (see Annex IV) on the
rotation angle of the control axle.
–Position the valve to the origin of travel that
should
correspond to the minimum of the signal (4 mA).
–Install a milliamp meter in series in the loop and
power up the instrument.
–Rotate the primary pinion on the control axle to
get an output signal around 4 mA
–Fine tune-up of the 4 mA signal with the zero
potentiometer (Z).
–Full stroke the valve to the rated travel and
adjust the output signal to 20 mA with the
span potentiometer (S).
–Check the zero and span calibration
compared to the valve stroke. Repeat the
zero and span calibration operations if
necessary.
* In case of problem of Zero adjustment due
to the physical limits of the potentiometer,
turn of 5 turns in the reverse direction that
desired
and turn the primary pinion to obtain an
output current nearest to 4 mA.
**In case of problem of span adjustment due
to the physical limits of the potentiometer,
turn of
5 turns in the reverse direction that desired
and configure the switch C (see Annex IV) for
a higher or lower angle than that basis.
• Adjustment of micro-switch(es) or
proximity switch(es)
Refer to paragraph §8.1 or §8.2 to adjust
micro-switch(es) or proximity switch(es).
• Strictly follow safety instructions under §7.4
before putting into service.

20 | Baker Hughes © 2020 Baker Hughes Company. All rights reserved.
8. Calibration (Cont’d)
9 10 11 8 12 23 111 44 110
7
8 220
22144 6
114
46
222
114
14
F
View F
Vue
108
106
105
101 102 103 104 38 42
107
Parts List
Rep. Designation Rep. Designation Rep. Designation
6
housing
38
spacer
106
Grower washer
7
O-ring
42
electronic card
107
stirrup
8
circlips
44
washer
108
washer
9
CHC screw
46
card support
110
screw
10
O-ring
101
ground screw (inside)
111
spring washer
11
shaft
102
Grower washer
114
CHC screw
12
cover
103
stirrup
220
detector set
14
serial plate
104
washer
221
detector support
23
pinion
105
ground screw (outside)
222
screw