Cashco 9540L P/P Bedienungsanleitung PDF herunterladen

I. DESCRIPTION AND SCOPE

Model 9540L is a single acting, compact, force bal-

ance, pneumatic positioner used on linear travel (slid-

ing stem) control valves. This positioner is utilized to

linearize the relationship between valve stem position

and the system’s control signal. This design is only

suitable for nominal 3-15 psig input signals, or split

range variations thereof.

Each unit comes complete with a set of built-in gages

within the internals; the cover includes a clear see-thru

panel to monitor gages. Gages monitor input “SIG”

and output “LOAD”.

The Model 9540L P/P positioner may be utilized with

the following current Cashco product models:

987 964 520 TFE SCV-30

988 2266 (2” size) 521 TFE

989 2296 SCV-S

IAS - Instrument Air Supply

PC - Pressure Controller

PCV - Pressure Control Valve

ATO-FC - Air-to-Open, Fail Close

ATC-FO - Air-to-Close, Fail Open

P/P - Pneumatic Input/Pneumatic Output

DIR - Direct Acting

REV - Reverse Acting

SIG - Controller Output Signal

V - Vent

CW - Clockwise rotation

CCW - Counter-clockwise rotation

II. METHOD OF OPERATION (See Figure 2)

The positioner operates with the force balance

principle: the input signal “SIG” (3-15 psig) acts on the

input diaphragm (50).The stroke of the input dia-

phragm is transferred to the flapper lever (38). The

resulting movement of the flapper varies the dynamic

pressure at the nozzle (51). This pressure acts on the

amplifier (53) and the change in output pressure

causes a movement of the actuator/valve stem.

This movement is back fed from the actuator/valve

stem (55) by the feedback lever (13) of the positioner,

and transferred to the stroke factor lever (19). The

stroke factor lever (19) is connected to the flapper

lever (38) by means of a range spring (41).

INSTALLATION, OPERATION & MAINTENANCE MANUAL (IOM)

IOM-9540L

06-99

MODEL 9540L

P/P - PNEUMATIC POSITIONER FOR LINEAR VALVES

SECTION I

SECTION II

Figure 1: Typical Pressure Reducing Pneumatic Control

Loop - PCV with P/P Positioner

PCV

5-13 psig

3-15 psig

LOAD

DIR.

P1 = 500 psig

ATO-FC

IAS

P/P

SIG

PROCESS

P2 = 100 psig

15-3 psig

IAS

20 psig

REV.

1 2 3 4 5 6 ... 11 12

Inhaltsverzeichnis

Seite 1 - MODEL 9540L

I. DESCRIPTION AND SCOPEModel 9540L is a single acting, compact, force bal-ance, pneumatic positioner used on linear travel (slid-ing stem) control va

Seite 2 - SECTION III

IOM-9540L10C. Replacing The Amplifier: (See Figure 13)1. Unhook the range spring (41) from the flapperlever (38). (See Figure 11.)2. Unscrew and remov

Seite 3 - IOM-9540L

IOM-9540L114. Unstable behavior; non-steady state in control loop.Possible Causes RemediesA. Amplification too high A1. Reduce amplification.B. Gland

Seite 4 - “right” mounting positions.)

Cashco, Inc.P.O. Box 6Ellsworth, KS 67439-0006PH (785) 472-4461FAX (785) 472-3539E-mail: [email protected] [email protected] in U.S.A.

Seite 5 - SECTION IV

IOM-9540L2A force balance is created on the flapper lever (38)when the force generated by the input diaphragm (50)balances with the counter-force prod

Seite 6 - SECTION V

IOM-9540L3CONTROL VALVE POSITIONER PLUG ACTIONCASHCO ACTION/FAIL MOUNTING ACTION CHANGEOVER STEM TRAVEL WITH SIGNALPRODUCT POSITION LOCATION PLATE SET

Seite 7 - Figure 9

IOM-9540L44. If the control valve does not have an accessoryplate (AP) installed, the actuator stem must be de-coupled from the valve stem. (Refer to

Seite 8 - SECTION VI

IOM-9540L5the connection port of the actuator casing. NOTE-Thread Sealants: If TFE tape is used, make surethat small pieces of tape will not be “pinch

Seite 9 - Figure 12

IOM-9540L6Applicable Range Spring (41)Valve Split Range Input ProductStroke Input Signal: 3-15 psig Signals: 3-9, 9-15, 3-7, Size - Model 7-11 and 1

Seite 10 - SECTION VII

IOM-9540L7d. Introduce an air supply (“IAS”) to the positioner asrequired by Table 2.e. Press the flapper lever (38) several times to theleft and righ

Seite 11 - REPAIR PARTS KITS

IOM-9540L83. A change in GAIN is normally indicated wheninstability sluggishness shows up at steadystate operating conditions. If the positioneroutput

Seite 12

IOM-9540L93. If adjustments are made with the positionermounted on the control valve, the feedback lever(13) on the main shaft (17) of the positioner

Kommentare zu diesen Handbüchern

Keine Kommentare

Cashco 9540L P/P Bedienungsanleitung

Stöbern Sie online oder laden Sie Bedienungsanleitung nach Zubehör fürs Wasser Cashco 9540L P/P herunter. Cashco 9540L P/P User Manual Benutzerhandbuch

Inhaltsverzeichnis

Kommentare zu diesen Handbüchern

Verwandte Produkte und Handbücher für Zubehör fürs Wasser Cashco 9540L P/P