Flowserve AF-17 User Manual

4.7 (3)

Worcester Controls

WCAIM2031

AF-17 Electronic Positioner

Installation, Operation and Maintenance Instructions

MODELS

20 – For AF-17 Boards Mounted Inside 10-23 75 Actuator. 30 – For AF-17 Boards Mounted Inside 25-30 75 Actuator. AF-17-1K, 120A or 240A, 1000 ohm Resistance Input AF-17-13, 120A or 240A, 135 ohm Resistance Input AF-17-1, 120A or 240A, 1 to 5 Milliamp Input

AF-17-4, 120A or 240A, 4 to 20 Milliamp Input

AF-17-10, 120A or 240A, 10 to 50 Milliamp Input

AF-17-5V, 120A or 240A, 0 to 5 VDC Input

AF-17-XV, 120A or 240A, 0 to 10 VDC Input

R – Reverse Action Option

120A-120 VAC Power Circuits

240A-240 VAC Power Circuits

Flow Control Division

Worcester Controls

TABLE OF CONTENTS

1.0 GENERAL

3

1.1

Basic Design

3

1.2

Environmental Considerations

4

 

1.2.1 Temperature

4

 

1.2.2 Positioner Temperature

4

 

1.2.3 Humidity

4

 

1.2.4 Input Circuit Noise Protection

4

2.0 ELECTRONIC CIRCUIT BOARD

6

2.1

General

6

2.2

Circuit Board Configurations

6

2.3

LED Indicators

6

2.4

Controls

6

 

2.4.1 Range

6

 

2.4.2 Zero

6

 

2.4.3 A-H

6

2.5

AC Power Control

6

3.0 INSTALLATION OF AF-17 INTO

 

3.0 SERIES 75 ELECTRIC ACTUATOR

7

3.1

General

7

 

3.1.1 Check Kit for Parts

7

 

3.1.2 Tools Needed

8

 

3.1.3 Operation Check of Basic Actuator

8

3.2

Mounting Potentiometer

8

 

3.2.1 Mounting Single Potentiometer Into

 

 

Series 75 Electric Actuator

8

 

3.2.2 Mounting Dual Potentiometer Into

 

 

Series 75 Electric Actuator

8

 

3.2.3 Potentiometer Wiring

8

 

3.2.4 Adjusting Potentiometer

9

 

3.2.5 Important Note

9

3.3

Mounting Circuit Board

11

 

3.3.1 For 120/240 VAC 10-23 Size Electric Actuators

11

 

3.3.2 For 120/240 VAC 25 and 30 Size Electric Actuators

12

 

3.3.3 For Optional 4-20 mA Position Output Installation

12

3.4

Wiring AF-17 Board to Actuator

13

 

3.4.1 Terminal Strip

13

 

3.4.2 Feedback Connections

14

 

3.4.3 Output Connections

14

 

3.4.4 For 10-30 AF-17 240 VAC Positioner Wiring

14

 

3.4.5 Wiring for AF-17 with 4-20 mA Position Output

14

3.5

Actuator Power

15

 

3.5.1 Wire Size

15

 

3.5.2 Terminations and Voltage

15

 

3.5.3 Minimum Fuse Ratings

15

3.6

Input Signal Connections

16

 

3.6.1 Milliampere

15

 

3.6.2 Resistive

16

 

3.6.3 Direct

17

 

 

 

4.0 CALIBRATION AND ADJUSTMENT

17

4.1

Initial Setup and Adjustment

17

4.2

Zero Adjustment

17

4.3

Range Adjustment

17

4.4

AH Adjustment

17

4.5

Adjustment Recheck

18

4.6

Operational Check

18

 

4.6.1 Increasing Signal

18

 

4.6.2 Decreasing Signal

18

 

4.6.3 Attaching Label

18

4.7

If Problems Occur

18

 

4.7.1 Cam Adjustment

18

 

4.7.2 Feedback Pot Calibration

18

 

4.7.3 Reverse Acting

18

 

4.7.4 Adjustment to Loop Process

18

 

4.7.5 Check Fuse F1

19

 

4.7.6 Check Basic Actuator for Proper Operation

19

 

4.7.7 Check for Noise Problems

19

 

4.7.8 Replace Circuit Board

19

5.0 OPERATIONAL VARIABLES

19

5.1

Sensitivity

19

5.2

Reduced Travel Operation

19

5.3

Split Range

19

5.4

Reverse Action

19

 

5.4.1 Milliampere Input

20

 

5.4.2 Resistive Input

20

 

5.4.3 Voltage Input

20

 

5.4.4 240 VAC

20

6.0 TECHNICAL DATA

20

6.1

AC Input Voltage

20

6.2

Input Circuit Specs

20

6.3

Output Circuit Specs

21

6.4

Input Circuit Characteristics

21

 

6.4.1 Input Circuit Load Resistances

21

 

6.4.2 Nominal Useable Input Signal Deadband

21

6.5

Controls

21

7.0

APPLICATION NOTES

22

 

7.1

DC Motor Actuator

22

 

7.2

Bypass Switch for Manual Control

22

8.0

TROUBLESHOOTING

23

 

8.1

General

23

 

8.2

Symptom Table

24

 

8.3

Troubleshooting Guidelines

25

9.0

SUGGESTED SPARES

27

2

AF-17 Electronic Positioner: Installation, Operation and Maintenance

WCAIM2031

Flow Control Division

Worcester Controls

1.0GENERAL

1.1Basic Design

The Worcester AF-17 Electronic Positioner was designed for use with the Worcester Series 75 actuators. However, it may also be used with other actuators or electrically operated rotary devices, provided the specified load parameters as given in Part 6.3 are not exceeded.

CAUTION: This positioner is sensitive to electrical noise; please see part 1.2.

PLEASE READ THIS SECTION

A.The AC AF-17 board 4-20 mA signal input circuit is protected with a 62 mA fuse (F1). The fuse is used to protect the input circuit from an excessively high voltage. The fuse used in the input circuit is a Littlefuse PICO II very fast-acting fuse rated at 62 mA. There is a spare fuse located on the circuit board in the area of the large power resistors.

B.The AF-17 board is designed to receive a floating current input signal. This allows several pieces of equipment to be operated from the same current loop while at the same time remaining electrically independent of each other.

C.The AF-17 board can be set up in several ways for normal operation. The board is designed to control in 90° quadrants only. The number of quadrants over which the board will control is determined by the number of teeth on the feedback pot pinion gear. The adjustment trimpots on the board were not set up to reduce actuator travel for a 4-20 mA input span. For example, trying to adjust the board such that 4 mA is closed and 20 mA is only 60% open is not possible with the standard set up.

The standard setups are:

1.4 mA for full clockwise rotation, i.e., 0°, and 20 mA for full counter-clockwise rotation, i.e., 90° or 180°.

2.Split range where 4 mA would be full clockwise and 12 mA would be full counter-clockwise or 12 mA would be full clockwise and 20 mA would be full counter-clockwise.

3.Each of the above standard setups can also be made reverse-acting.

Quadrants of Operation

Standard 90° Actuator

180° Center-Off Actuator

Series 75W, X, and Z Shown

Series 75W, X, and Z Shown typical

D.Quite often when we receive an actuator for repair at Flowserve we find that the only thing wrong with the unit is that the feedback potentiometer is out of calibration. It is very important that the feedback pot be properly calibrated for correct operation of the positioner board. It is also very important that the actuator shaft not be rotated out of the quadrant for which the feedback pot has been calibrated. Whenever you have a problem with the positioner calibration, always check the feedback pot calibration first. This must be done with no power applied to the circuit board. If the actuator is in the full clockwise position, check the resistance between the purple and white/black potentiometer leads. The reading should be 80-90 ohms. If it is not, rotate the face gear until the proper reading is achieved. If the actuator happens to be in the full counter-clockwise position then check the resistance between the green and white/black potentiometer leads. If necessary, adjust the face gear for an 80-90 ohm reading. NOTE: It is not necessary to loosen or remove face gear snap ring(s) to rotate gear; it is a friction fit.

WCAIM2031

AF-17 Electronic Positioner: Installation, Operation and Maintenance

3

Flow Control Division

Worcester Controls

1.2 Environmental Considerations

CAUTION: The AF-17 Electronic Positioner is sensitive to electrical noise on signal or supply lines and in the environment. For maximum sensitivity, the electrical noise level should not exceed 10mV. Follow installation, calibration and adjustment guidelines carefully and use shielded wire as stated in paragraph 1.2.4.

Flowserve recommends that all products that must be stored prior to installation be stored indoors, in an environment suitable for human occupancy. Do not store product in areas where exposure to relative humidity above 85%, acid or alkali fumes, radiation above normal background, ultraviolet light, or temperatures above 120°F or below 40°F may occur. Do not store within 50 feet of any source of ozone.

Temperature and humidity are the two most important factors that determine the usefulness and life of electronic equipment.

1.2.1Temperature

Operating solid-state electronic equipment near or beyond its high temperature ratings is the primary cause for most failures. It is, therefore, very important that the user be aware of and take into consideration, factors that affect the temperature at which the electronic circuits will operate.

Operating an electronic device at or below its low temperature rating generally results in a unit operating poorly or not at all, but it will usually resume normal operation as soon as rated operating temperatures are reached. Low temperature problems can be easily cured by addition of a thermostatically controlled heater to the unit’s housing.

At high temperatures, some components will destruct completely when their maximum temperature is exceeded; others will cease operation at temperatures above ratings and will return to operation at normal ratings, but may have been permanently changed in one or another parameter, causing a device to operate poorly, and may also cause greatly reduced component life.

1.2.2Positioner Temperature Considerations

The Worcester AF-17 Electronic Positioner is rated for operation between -40°F and 160°F. When using the positioner inside the Worcester 75 Series actuators, a maximum ambient temperature of 115°F is required to ensure the circuit board maximum temperature of 160°F is not exceeded.

1.2.3Humidity

Most electronic equipment has a reasonable degree of inherent humidity protection and additional protection is supplied by the manufacturer, in the form of moisture proofing and fungicidal coatings.

Such protection, and the 3 to 4 watts of heat generated by the circuit board assembly will generally suffice for environments where the average relative humidity is in the area of 80% or less and ambient temperatures are in the order of 70°F average with only occasional short term exposure to temperatures up to 90°F. Where relative humidity is consistently 80 to 90% and the ambient temperature is high or subject to large variations, consideration should be given to installing a heater and thermostat option in the enclosure. The heater should not increase the enclosure temperature to the point where the circuit board assembly’s temperature rating of 160°F is exceeded.

In those instances where the internal heater would bring the circuit board’s operating temperature near or above its maximum rating, the user might consider purging the enclosure with a cool, dry gas. The initial costs can usually be paid off quickly in the form of greatly extended equipment life, low maintenance needs, and much less process downtime.

1.2.4Input Circuit Noise Protection

Shielded wiring should be used for all signal input circuit wiring regardless of length.

With separately housed positioners, the wiring from the feedback potentiometer to remote positioner, would be considered as signal input wiring and should also be shielded wire.

The shields should never be used in place of one of the input wires, and the shields normally should be grounded to equipment housings at one end of the wiring run only. Grounding both ends of shielding can eliminate the shielding benefits because of current ground loops. If two or more shielded cables come to the positioner from different locations, ground the shields at the positioner.

4

AF-17 Electronic Positioner: Installation, Operation and Maintenance

WCAIM2031

Flowserve AF-17 User Manual

Flow Control Division

Worcester Controls

Figure 1 – 120 VAC AND 240 VAC POSITIONER CIRCUIT BOARD

NOTES:

J1 and J2 with red and black wires are on 240 VAC board only.

Use or values of components R13, R24, R52, R53, R54, C22, J3, J4 and orange wire will vary depending on input signal.

R5 and R7 used only for 25 and 30 size actuators.

WCAIM2031

AF-17 Electronic Positioner: Installation, Operation and Maintenance

5

Flow Control Division

Worcester Controls

2.0 ELECTRONIC CIRCUIT BOARD (120/240 VAC)

2.1 General

Figure 1 defines the location of major components and wires from the positioner to terminal strip connections. The #18 gauge white wire is the AC power unit “neutral” (or common) in the case of DC input wire. The #20 gauge white/black wire is one of the connections between the feedback pot and the terminal block (TB-1) on the circuit board.

2.2 Circuit Board Configurations

The positioner board is factory supplied for one of the seven input signal options.

NOTE: Field changes to the positioner board are not advised. Consult Flowserve before attempting any modification.

2.3 LED Indicators

Light emitting diodes (LED) marked LD1, LD2 and LD3 are in the output circuits of amplifier U4. LD1 is tied to pin #13, LD2 to pin #14, and LD3 to pin #1, and they are each associated with their respective opto-coupler U1, U2 and U3 and indicate when the input side of the opto-coupler is energized.

2.4 Controls

Three adjustment potentiometers are provided, located on the top side of the board and marked “Range”, “Zero”, and “AH”. See Figure 1.

2.4.1Range

The “Range” Control adjusts the positioner’s feedback circuit to cover the same span of voltage as generated by the input signal.

2.4.2Zero

The “Zero” adjustment is basically an offset adjustment in that essentially all input signals start at other than a zero signal condition, i.e., 1, 4 or 12 milliamps.

2.4.3A-H

The “AH” Control is used primarily to balance the positioner to the dynamic characteristics of the device and media being controlled. Functionally, it varies the amount of input signal that must be applied to the positioner to cause the actuator to reverse its direction of rotation. In effect it varies the deadband of the positioner on a reversing signal condition only. The deadband — the percent change in input signal change that must be applied to initiate a movement of the actuator — on a signal that is constantly increasing or decreasing, is relatively unaffected by the “AH” control.

The “AH” control can vary the balance point deadband from approximately .3% to 4.0% of signal span. It can therefore be used to help decrease the effects of signal noise, with a tradeoff in accuracy/sensitivity.

2.5AC Power Control

The AC output circuits are controlled by solid-state switches (triacs Q1, Q2, Q3), which will provide trouble-free operation for the life of the equipment they are used with, AS LONG AS THEY ARE OPERATED WITHIN THEIR RATINGS.

The ratings for the solid-state switches used in the Worcester AF-17 Positioner are listed in Part 6.3.

6

AF-17 Electronic Positioner: Installation, Operation and Maintenance

WCAIM2031

Flow Control Division

Worcester Controls

3.0 INSTALLATION OF AF-17 INTO SERIES 75 ELECTRIC ACTUATOR

3.1 General

If the actuator was purchased with the AF-17 positioner board factory installed, proceed to section 4.0.

If a 4-20 mA Position Output option is also used with the AF-17 positioner, refer to paragraph 3.3.3 for installation (if not already installed), and paragraph 3.4.5 for wiring.

3.1.1Check Kit For Parts

A. Common Parts For Sizes 10-30 Actuators

 

 

Quantity

Name

1

Circuit Board Subassembly

1

Insulating Board

5 or 6

Washers (Nylon)

5 or 6

Grommets (Rubber)

5 or 6

Mounting Screws (Circuit Board)

1

Nameplate – Circuit Board

1

Nameplate – Base

1

Wiring Label – Cover

1

Instruction Manual

5

Cable Ties

2

Closed End Splice

1

Wire – White

 

Additional Parts For 10-23 Actuators:

 

 

Quantity

Name

1

Pot Kit Subassembly

1

Bracket – Right (Long)

1

Bracket – Left (Short)

2

Spacer (Bracket)

2

Mounting Screw (Bracket/Spacer)

1

Support Bracket – Transformer

1

Spacer – Transformer Support Bracket

 

(for 23 Size Only)

 

Additional Parts For 25 and 30 Actuators:

 

 

Quantity

Name

1

Pot Kit Subassembly

1

Mounting Bracket

2

Mounting Screw (Bracket)

 

 

WCAIM2031

AF-17 Electronic Positioner: Installation, Operation and Maintenance

7

Flow Control Division

Worcester Controls

3.1.2. Tools Needed

1/4" nut driver, 1/8" screwdriver, needle nose pliers, 1/16" Allen wrench (cams and spur gear).

Volt/ohm meter (checking feedback potentiometer resistance, voltages – incoming process signal).

Milliamp source (to check calibration of positioner on actuator).

VAC line cord (to power basic actuator).

3.1.3. Operation Check of Basic Actuator

Set cams for about 1° to 3° of over travel in each direction (full open and full closed). That is, for 0° to 90° operation set at minus 3° and plus 93°. Power terminals 1 and 3 for CCW rotation, terminals 1 and 4 for CW rotation (reference paragraph 4.7.6.).

3.2Mounting Potentiometer

3.2.1Mounting Single Potentiometer Into Series 75 Actuator See Figure 2.

A.With the potentiometer mounted to the potentiometer bracket and the spur gear loosely fitted to the potentiometer shaft, mount the potentiometer bracket (if not already mounted) as follows:

10-23 75 Actuator:

Remove the motor module mounting screws on the side of the module furthest away from the actuator shaft. Position potentiometer assembly bracket holes over screw holes and line up potentiometer shaft with center of actuator shaft, replace and tighten screws.

25/3075 Actuator:

Attach potentiometer bracket to motor support plate between the terminal strip and actuator shaft with mounting screws as shown.

3.2.2Mounting Dual Potentiometer Into Series 75 Electric Actuator

Adual potentiometer is also available and is required with the AF-17 when external resistance indication is also desired, or when the 4-20 Position Output option is also used.

Each potentiometer can serve only one function. Remote resistance monitoring and an AF-17, for instance, cannot share a potentiometer.

Note: Voltage limit of “B” potentiometer is 30 volts maximum.

Mount potentiometer per paragraph A of 3.2.1.

3.2.3Potentiometer Wiring

A.The feedback potentiometer leads are connected to the terminal block (TB-1) on the AF-17 board. Run the three leads up through the hole next to potentiometer R29. See Figure 1.

B.Connect the potentiometer leads to the terminal block as follows:

 

TB-1

Terminal

Wire Color

 

 

 

1

Purple

2

White/Black

3

Green

(DO NOT CUT POTENTIOMETER WIRES!)

NOTE 1: In the case of a dual potentiometer, “A” (front, close to the bracket) potentiometer wires are wired to the AF-17 board terminal block (TB-1) as stated above, “B” (rear, far from the bracket) potentiometer wires may be wired to terminals 7 (green), 8 (white/black), and 9 (purple) if available and the potentiometer will be used for resistive feedback, or they may be wired to TB-2 if 4-20 mA position output option is used. The wires are run up through the hole next to Q4 then connected to TB-2 as follows:

8

AF-17 Electronic Positioner: Installation, Operation and Maintenance

WCAIM2031

Flow Control Division

Worcester Controls

 

TB-2

Terminal

Wire Color

 

 

 

1

Green

2

White/Black

3

Purple

(DO NOT CUT POTENTIOMETER WIRES!)

3.2.4Adjusting Potentiometer

A.Reference paragraph 4.7.6 for moving the actuator shaft electrically.

B.10-30 75 Actuator:

Place the large face gear (12) over the actuator shaft with the gear teeth down and secure with snap ring (16).

NOTE: The face gear utilizes a friction fit to the shaft. For best results, wipe off any lubricant that may be on the shaft before sliding on the face gear.

CAUTION: Do not overstretch the snap ring — use the minimum opening to allow them to slip over the gear.

C.Adjust the potentiometer spur gear until there is approximately 1/16" engagement with the large face gear. Ensure there is minimum backlash between the gears. Tighten the spur gear set screw.

D.Rotate the face gear back and forth to ensure smooth and easy operation of the potentiometer.

E.IMPORTANT: For 90° Valves:

Depending on whether the AF-17 board is installed and wired, either measure the resistance directly at the potentiometer wires if not installed or at the AF-17 terminal block (TB-1) if installed and wired. With the actuator either in the OPEN (full CCW) or CLOSED (full CW) position, and power off, rotate the face gear, thus turning the potentiometer shaft, until the resistance between the white/black lead (AF-17 terminal 2) and the green lead (AF-17 terminal 3) or the white/black lead (AF-17 terminal 2) and the purple lead (AF-17 terminal 1) respectively, as measured by ohmmeter, is between 80 ohms and 90 ohms.

NOTE: It is not necessary to loosen or remove face gear snap ring(s) to rotate gear.

F.Power the actuator to the opposite position from where resistance was measured. Reference paragraph 4.7.6 for moving actuator shaft electrically.

G.At this position, with power off, measure the resistance at the same terminals as stated above. The resistance reading should be greater than 700 ohms. If not, then power actuator back to original position and adjust potentiometer again, if necessary, as stated in paragraph E above. If unsuccessful in getting proper resistance readings, potentiometer is defective and should be replaced.

H.The feedback potentiometer is now adjusted for use in the 75 actuator. Add the potentiometer caution label to the outside of the actuator cover.

CAUTION: If the actuator shaft is manually rotated a multiple of 360° from its original position, the feedback potentiometer will no longer be in calibration. It must be recalibrated per paragraphs E-G above, in order for the AF-17 board to operate properly.

3.2.5Important Note

The feedback potentiometer is calibrated for only one 90-degree quadrant of valve operation.

If the valve and actuator output shaft is repositioned to another 90-degree quadrant the feedback potentiometer must be recalibrated as per Section 3.2.4.

The Series 75 actuators offer a manual override feature. Whenever repositioning the valve using the manual override capability on these actuators, move the valve only within the 90 degrees for which the feedback potentiometer has been calibrated.

WCAIM2031

AF-17 Electronic Positioner: Installation, Operation and Maintenance

9

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