PMV P-2000, P-2020, P-2000 Ex, P-2050, P-2020 Ex User Manual

Manual

P-2000 P-2020
P-2000 Ex
P-2020 Ex
P-2050

Manual

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Contents

Page

Function 5

Air preparation 6

Installation 6

1. Calibration

1.1 Cam setting 7

1.2 To change the action 7

1.3 Gain adjustment 7

1.3.1 To reduce the gain 8

1.4 Zero adjustment 8

1.5 Range adjustment Maintenance 8

2.1 The restriction plug 8

2.2 To clean the valve body 8-9

2.3 To replace the diaphragms 9-10

Trouble shooting
11

Ex installation 12-13

Exploded drawing 14

Dimensional drawing 15

Manual

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Manufacturers declaration • Hersteller-Erklärung • Déclaration de fabricant

GB

Manufacturers declaration

in compliance with EC directive 89/392/EEC/89/336/EEC, & 92/31/EEC

We hereby conrm that the appliances described in this sheet has been manufactured in compliance

with the applicable standards and is intended for installation in a machine/application, and that com-

missioning is strictly prohibited until evidence has been provided that the machine/application

in question is also in compliance with

EC directive 89/392/EEC/89/336/EEC, and 92/3/EEC.

This manufacturers declaration is applicable to the following PMV series:

P-2000/P-2020/P-2050/P-2000Ex/P-2020Ex

D

Hersteller-Erklärung

im Sinne der EG-Richtlinie 89/392/EWG/89/336/EWG, & 92/31/EWG

Hiermit erklären wir, daß die in diesem Blatt beschriebenen Geräte entsprechend den gültigen Normen

gebaut und zum Einbau in eine Maschine oder Applikation bestimmt sind, sowie daß deren Inbetrieb-

nahme so lange untersagt ist, bis festgestellt wurde, daß diese

Maschine/Applikation ebenfalls der EG-Richtlinie

89/392/EWG/89/336/EWG, 92/3/EWG entspricht.

Diese Herstellererklärung hat für folgende PMV-Serien Gültigkeit:

P-2000/P-2020/P-2050/P-2000Ex/P-2020Ex

F

Déclaration de fabricant

au sens dela directive de la 89/392/CEE/89/336/CEE, & 92/31/CEE.

Nous déclarons par la présente que les appareils décrits sur cette page sont construits en conformité

avec les normes en vigueur et qu'ils sont destinés à être montés dans une machine ou une application,
nous déclarons également que leur mise en service est interdite tant qu'il n'a pas été constaté que cette

macine/application satisfait

également à la directive 89/392/EEC/89/336/EEC, 92/3/EEC.

Cette déclaration de fournisseur est valable pour les types d'appareils PMV suivants:

P-2000/P-2020/P-2050/P-2000Ex/P-2020Ex

Mr. Jan-Eric Andersson

President, Palmstiernas Instrument AB

Manual

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PMV Positioner storage and handling procedures

PMV Positioners are precision instruments which should be stored and hand­led accordingly to avoid problems or damage.

Appropriate precautions should be taken to protect units while in storage.

.

Warehouse storage

Stored in original PMV shipping containers, units should be stored in an en­vironmentally controlled area, i.e. clean, cool (15-26°C, 6-80°F) and dry, out

of direct sunlight or weather exposure.

Field storage

Note: Once air supply to the positioner is connected and turned on, internal
air bleed will prevent the ingress of moisture and protect the unit from cor­rosion. It is recommended that the air supply be left on at all times.

• If units are installed immediately, tum, and leave on, the air supply.

• If positioner must be stored outdoors, tighten all covers which may loosened

in shipment, make sure all open enclosure entry points are sealed.

Positioners should be wrapped and sealed air and watertight with desiccant
inside the plastic, units should be securely covered with an opaque cover and
not exposed to direct sunlight, rain or snow.

Potential damage mechanism

When units are stored in hot, humid climates, the daily heating/cooling cycle

will cause air to expand/ contract and be drawn in and out of the positioner

housing.

Dependent on the local temperature variations, humidity, dew points and
the time in storage condensation could occur and accumulate inside causing

erractic operation or failure due to water or corrosion. The potential for con­densation damage is especially high in southern climates and aggravated if

units are exposed to direct sunlight.

For further assistance, please contact your nearest PMV ofce.

Manual

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Function

The PMV E/P Positioner function is based on torque

balance. Direct current, 4-20 mA or 0-20 mA acting as

input signal creates, in the force coil (53) in the per­manent magnet (50) eld, a force proportional to the

signal and, on the beam (92), a corresponding torque

The position of the cylinder (C) piston is converted
by means of the feedback linkage (L), cam (42), lower
arm (21) and spring (40), to a force proportional to the
position of the cylinder (C) piston and, on the beam

(92) a counter torque. When in balance, the cylinder
position equals the input signal value.

The nozzle (114) without friction senses the balance of
the beam (92). When, for example, the signal is increased

the torque corresponding to the signal on the beam (92)
will increase and the beam (92) will turn clock-wise.
The nozzle (114) closes, and the nozzle pressure in­creases. The diaphragm assembly moves downwards

as does the spool (68) of the pilot valve activated by the
balancearm (57). Supply airows through connection
C2 andairfrom the ”minus” chamberofthe cylinder(L)

is exhausted through connection C1.

Differential pressure is created in the cylinder, and the
piston will travel ”plus” until the torque change on

the beam (92), created by the piston position change,
rebalances the beam (92) positionand the nozzle pres­sure. The diaphragm assembly will return to equili­brium position with the balance arm (57) guiding the

spool (68) to mid position. The piston of the cylinder

(C) will stop in the position corresponding to the new
input signal.

A change in position ofthe balance arm (57) creates,
through the spring (93), anegative feedback torque on

the beam (92). Stable operationis thus achievedin spite

of possible great static amplication or sensitivity. The

position of the spring (93) can be changed along the

beam (92) and the balance arm (57) in order to adjust

positioner gain, and thus the dynamics of the positioner.

The positioner can be adjusted to match any small or
large actuator.

The lower arm (21) has a mechanism for zero adjust­ments. The beam (92) has the mechanism for adjusting

the range. To reverse the positioner action the cam (42)

is ipped over and the pipe cormections C1 and C2

are interchanged.

Split range is available by choosing the right curve on the

cam (42). Non-linear function is achieved by reshaping
the cam (42). Such cams are available from PMV.
The PMV E/P Positioner can also be used as a single
acting positioner by simply plugging one of the

ports C1 or C2.

Manual

– 5 –

Air preparation

The PMV ELECTRO-PNEUMATIC Positioner

can work with supply pressure up to 8 bar ( 120

Psi”). In order to obtain a satisfactory operation
and high reliability a lter (25 microns) should be

placed as close to the Positioner as possible.

For larger pressure variations of the supply air

(or the supply pressure is too high) a pressure

regulator should be mounted next to the lter in
order to eliminate the uctuations. The supply
air must be dry, clean and free from oil.

Installation

The PMV E/P Positioner is available with a large
selection of feed back spindle designs to simplify

the mounting on the actuator.

Port I is to be used for the electrical connection

gland. This connection is 1/2~ NPT or PG 13.5
(M- 20) internal thread.

Input signal: 4-20 mA; 0-20 mA

Input resistance: 240 Ohm±10%

Important notice

Ports C I and C2 are to be connected to the ac­tuator.

Port S is to be connected to the air supply (max

8 bar or 120 psi3 which should be of instrument
quality (clean, dry and oil free). If your supply

pressure is too high and/or the supply pressure
changes from time to time you must use a pres­sure regulator.

P-2000 Ex/P-2020 Ex should be connected to

intrinsically safe circuits only. See installation
dwg for further details.

Manual

The PMV Positioner with the cover (33) and the side frame
(3) dismounted.

– 6 –

1. Calibration

PLEASE NOTICE: For easy

acsess to important parts

please back off the four screws.

Remove the cover.

Fig 1

Figure 1

Position the cam as shown. The
ball bearing should not ride

on the inactive portion of the

cam. Tighten the nut.

Fig 4

NOTE: The cam will turn

slightly with the nut as it is

tightened. Be sure to allow for

this slight clockwise rotation.

Figure 4

The side frame can be removed

by simply pressing out one end

of the frame from the slot in
the main frame.

Fig 2

NOTE: P-2000 series positio­ner are factory calibrated to

4-20 mA input signal. Start

by adjusting zero rst, then

stroke the unit and check
reading before further ad­justments.

1.1 Cam setting

After mounting the PMV

Positioner on your actuator

and before switching on the
supply air, if possible, ma-

nually operate the actuator
from fully open to fully clo­sed position and check that
the cam is correctly oriented.
Make adjustments if necces­sary (see instructions below).

Figure 2

1.2 To change the action

To change the action, the cam

must be ipped over and the

tubes to the connections C1
and C2 must change places.

Fig 5

1.3 Gain adjustment

PLEASE NOTE: Before adjus­ting the gain please switch of

the supply pressure.

The gain surpression spring
can be moved along the beam
and the balance arm. The

feedback stiffness can thus
be adjusted so that the PMV

Positioner dynanics matches
the actuator size.

Fig 6&7

You will nd a number of posi­tioning holes in the beam and

the balance arm for the spring.

The smaller the actuator the
lower is the acceptable level

of the gain.

Figure 5

Should manual operation of

the actuator not be possible we

recommend you to back off the

nut holding the cam.

Fig 3

Adjust the position of the cam

so that the ball bearing on the
lower arm rests on the lowest

part on the correct curve of
the cam. You have three dif­ferent curves to choose from

on the standard cam (0-100,

0-50 or 50-100 % of the control
signal for the full stroke of the

actuator).

Manual

High gain

Figure 6

Figure 3

Low gain

Figure 7

– 7 –

1.3.1 To reduce the gain

Move the spring to the left.
Please use a pair of tweezers

when moving the spring.

Fig 8

Changing the position of the
spring effects the zero adjust-

ment and new zero adjustment
is neccessary (see 1.4 below).

1.4 Zero adjustment

Set the input signal at 4 mA

(or 0 mA for 0-20 mA control

range) and switch on the air
supply.

When turning the zero setting
screw to the right the actuator

will move in the direction of

the decreasing signal. Adjust
the screw until the actuator is

in the ”starting” position.

Fig 9

1.5 Range adjustment

Set the input signal at its nal

value e.g. 20 mA.

If the turning angle of the

actuator is too large (small) a
downwards (upwards) rota-

tion of the range adjustment

screw will reduce (increase)
the actuator travel.

Fig 10

Figure 8

Figure 9

Figure 10

a very strong magnetic eld

and in order to avoid iron dust
entering into the narrow gap

for the force coil you should
never leave the PMV E/P

Positioner without the cover
mounted.

Regular maintenance of the
PMV E/P Positioner is not
required. The need for main-

tenance is depending on your
supply air quality. Should iron
dust enter into the magnet,

restricting the free movement
of the force coil , this would

cause distur-bances.

2.1 The restriction plug

Close to the connection (S)

for the supply air you will
find the restriction plug

which is easily removable
for exchange. Before repla­cing the restrictor plug please

check that the Orings are in

good condition.

Fig 12

2.2 To clean the vahe body

Unscrew the four screws and

and remove the cover.

Fig 13

Figure 12

The range and zero adjust-

ments has a small effect on
one and other. Therefore a
few zero and range adjust-

ments might be needed in
turns.

PLEASE NOTICE: Should tbe

zero adjustment reach the limit
you might be helped by using
the other spring mounting on

the spring guide. Use a pair of

tweezers to change the posi-

tion of the spring.

Fig 11

2. Maintenance

The permanent magnet has

Manual

Figure 11

Remove the side frame.

Fig 14

Figure 13

Figure 14

– 8 –

Remove the screw (30) and the
indicator.

Fig 15

Before retting the valve body and spool check that
the O-rings are mounted and in good condition. Take
care not to damage the leaf springs on the tip of the
balance arm. Both leaf springs must be in the gap of
the spool. Using a small screw driver to atten the leaf

springs will help you slide the spool in place.

Remove the nut and the cam.

Fig 16

Remove the three screws hol­ding the valve body.

Be careful not to damage the

Magnet unit.

Fig 17

Carefully remove the valve

body. Handle so that the spool
slides easily and does not bind

against the tip of the balance

arm.

Fig 18

Figure 15

Figure 16

Figure 17

Figure 18

Fit the screws and tighthen the screws a little at a
time.

Fig 19

2.3 To replace the diaphragms

Back off the four screws and
remove the cover. See g 13.
Remove the sideframe. See

Figure 19

fig 14. Remove the screw
and the indicator . See g 15.

Remove the nut and the cam.

See g 16.

Disconnect the control signal
wires.

Fig 20

Figure 20

Use a pair of plairs to unload
the tension of the spring by
lifting the end of the spring

over the screw.

Fig 21

Pull the spool out of the valve body.

Wash the components in a solvent using e.g. a pipe-

cleaner for the valve body and blow the internal of the

valve body clean and dry using compressed air.

Parts should be handled with caution. Spool and valve
body are matched together and can not be changed
separately.

The spool should move freely in the valve body and
with the spool oriented in the ”closed position” the

play between the spool and the valve body seats

should be fairly tight. Should it be possible to move
the spool in the radius direction due to wear or if the
spool cannot be moved freely along its axes the valve

body with the spool must be exchanged.

Manual

Remove the screws and

Figure 21

the valve body. See g 17

and 18.

Remove the screws.

Fig 22

Figure 22

– 9 –

Carefully lift out the E/P

converter.

Fig 23

The middle section can

now be separated from the

body.

Remove the gain supres-

sion spring by using a pair of

tweezers.

Fig 24

Loosen the screw and be care­ful to use a holding-up tool for

the retainer to avoid tension
on the diaphragms.

Fig 25

Figure 23

Figure 24

Figure 25

Figure 26

Pull the diaphragm-piston

assembly upwards apart from

the middle section.

Fig 27

Figure 27

Replace the broken diaphragm and assembly the

positioner step by step following the opposite order

in which you now have disassembled it.

Be sure to check that all O-rings are in good condition

and in the proper places.

Manual

– 10 –

Trouble Shooting

Signal change has no effect on the actuator position.

– Make sure the supply pressure is switched on.
– Signal wires are wrongly connected.
– The wiring between the terminal block and the printed circuit board on

the force coil is broken. Check resistance.
– Pipe connections between the PMV Positioner and the actuator is wrong.
– A wrong portion of the cam is being used.

With a small change in the control signal the actuator runs to the end po­sition.

– Pipe connections between the PMV Positioner and the actuator is wrong.

Inaccurate positiomng

– Dirty valve body.
– Dirty restrictor or nozzle.
– Iron dust in the magnet gap.

– Defective diaphragms.
– The sizing of the actuator is incorrect. Output torque of the actuator is too

small or the supply pressure is too low.

– Torque requirement of the valve has increased.

Overshoot or hunting during positioning.

– Internal gain is too high.

– Capacity of the supply pipe is too small or air lter is clogged. In this
event the input pressure to the PMV Positioner drops steeply when
the pilot valve feeds air into the actuator.

Manual

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Manual

– 12 –

Manual

– 13 –

Exploded drawing

Manual

– 14 –

Dimensional drawing

Manual

– 15 –

SUBSIDIARIES:
PMV GmbH

PMV Controls Ltd

Headlands Business Park
Ringwood
Hampshire BH24 3PB

ENGLAND

Tel: [phone]
Fax: [phone]
E-mail: [e-mail]

PMV-USA, Inc

1440 Lake Front Circle
Unit 160

The Woodlands, Texas 77380

USA
Tel: [phone]
Fax: [phone]
E-mail: [e-mail]
Internet: www.pmvusa.com

Palmstiernas Instrument AB
Korta Gatan 9
SE-171 54 Solna
SWEDEN
Tel: [phone]
Fax: [phone]
E-mail: [e-mail]
Internet: www.pmv.nu

Postfach 2310

D-41554 Kaarst
GERMANY

Tel: [phone]
Fax: [phone]
E-mail: [e-mail]
Internet: www.pmv-germany.de

Palmstiernas Svenska AB

Box 21
SE-663 21 Skoghall
SWEDEN

Tel: [phone]
Fax: [phone]
E-mail: [e-mail]
Internet: www.palmstiernas.se

13794/2002.7 Ekvator

Distributor

Manual

(The information in this brochure is subject to change without notice.)

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