BEIFANG VALVE ACTUATOR 920 Series User manual

920 SERIES ELECTRIC ACTUATORS
FOR MULTI-TURN APPLICATION
INSTRUCTION MANUAL
TIANJIN BEIFANG VALVE ACTUATOR CO.,LTD
BF/TM-920.03-E2016A
Issue 201603


Tianjin Beifang Valve Actuator Co.,Ltd. 920 series Instruction Manual
1
Thank you for purchasing
and using our products. This
manual is valid for 920 series
electric multi-turn actuators.
Please before you operate
your product, be sure to read this
booklet carefully. These operation
instructions are only valid for
“clockwise closing”, i.e. driven
shaft turns clockwise to close the
valve
Address: Yi Xing Fu Science & Technology
Area Beichen District, Tianjin 300410, China
Tel: [phone] 26309159
Fax: [phone]
http://www.tj-beifang.com
e-mail: [e-mail]
Please tell us some information about your
product when contact us:
Model, Factory number, Manufacturing date
WHERE TO FIND INFORMATION
1. Summarize
1.1 Brief
1.2 Range of application
1.3 Warnings and notes
2. Performance parameters
3. Identifiers
4. Structure
4.1 Size 9201
4.2 Sizes 9202~9205
5. Transport and storage
5.1 Transport
5.2 Storage
6. Lubrication
7. Installation
7.1 Installing handwheel
7.2 Installation to valves or gearboxes
7.2.1 Plug sleeve connection
7.2.2 Stem nut connection
8. Electrical connection
8.1 Before wiring
8.2 Wiring
9. Manual operation
10.Setting the torque switch
11.Setting the limit control mechanism
11.1 Setting the limit switch
11.2 Setting the counter
12.Setting the position indicator
13.Installing the cover
页码
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6
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8
8
8
8
9
9
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Tianjin Beifang Valve Actuator Co.,Ltd. 920 series Instruction Manual
2
920 series electric multi-turn actuators provide a reliable position control of
gate, stop valve, as well as similar ones, and they can be combined with
gearbox. About other applications, please contact us.
For any damage caused by improper use, the manufacture is not
responsible for warranty. Such risk shall be borne by user alone. Strictly
complying with the instruction manual is part of the operational requirements.
1. Summarize
1.1 Brief
1.2 Range of application
• 920 series electric multi-turn actuators powered by electric have limit and
torque switch in both end position. In addition they can output torque or
thrust.
• According to customer’s requirements, 920 series electric actuators can be
made the standard type, integral control with open/close, integral control
with regulator module.
1.3 Warnings and notes


Non-observance of the warnings and notes may lead to serious injuries or
damages. Qualified personnel must be thoroughly familiar with all warnings
and notes in these operation instructions.
This sign means：Hint！
Explain the topic in detail.
This sign means ：Note！
Non-observance of these notes may lead to the blight to products or
the failure of operation.
This sign means ：Warning！
If not carried out the “warnings” correctly can affect the safety of
persons or material.

Tianjin Beifang Valve Actuator Co.,Ltd. 920 series Instruction Manual
3
Standard: 2-G3/4”
Options: 2-NPT1”
2-M33×2
Or according to user need.
Conduit entries
Automatic reset structure for motor mode first. Whenever the motor is
energized, the clutch automatically revert to motor mode in order to ensure
safe operation
The electric actuator can be locked by additional lock.
Hand /auto switch
Continuous display of adjustable dial with “Open” and “Close” mark.position indicator
Torque switches are provided for “Open” and “Close” separately
Standard:1NC and 1NO.
Options：Add up to two torque switches (On and off can be specified by the
user).
Torque control
Limit range of counter from ”Open” to “Close”.
Standard: 1~50 turns.
Options：1~490 turns
Travel switches are provided for “Open” and “Close” separately.
Standard: 1NC and 1NO ( Switches on and off can be changed on the
worksite ).
Options: 1NC and 2NO( Switches on and off can be changed on the
worksite ).
1NC and 3NO ( Switches on and off can be changed on the
worksite ).
Add up to four the middle position switches.
Limit control
Have. The actuator is not self-locking when the output speed is more than
48r/min.
Self-locking
Standard: F, heat resistance.
Options: H, heat resistance.
Insulation grade
A temperature protection switch embedded in the windings of the motor will
trip the actuator control circuit if the motor winding overheat.
Protection
Standard: 380V/50Hz/3ph AC, voltage vibration range:±10％, frequency
vibration range:±5％.
Options: 220V/50H/1ph AC (Apply to 9201 and 9202).
Power
Standard: S2-15 minutes short time work type. No more than 15 minutes
cyclic running time, the startup interval is 2～3 times running time.
60 starts/hour for application, do not exceed 600 starts/hour
when adjusting.
Options: S4-25% intermittent work type. Used for precise adjusting, do not
exceed 1200 starts/hour.
Work type
2. Performance parameters

Tianjin Beifang Valve Actuator Co.,Ltd. 920 series Instruction Manual
4
Options: Flashing switch for runningRunning indicator
Standard: IP65 (GB4208-2008)
Options: IP67 (GB4208-2008)
IP68 (Protection from dust and operating 10 times when
submersing in water to a depth of 3m for 48 hours.)
Ex-proof type: ExdⅡCT4 Gb（GB3836.1-2010、3836.2-2010）
Protection provided by
enclosure
Standard: Epoxy and acrylic acid coating.
Options：Other coating required by customer。
Coating
Standard: Gray (RAL7030)
Option: Other color required by customer.
Coating color
Ambient humidity below 90% (25℃).Humidity
At least 8000 times.（Cycle of operation: Open—Close—open, each cycle is
20 turns).
Lifetime
Standard: Installing the actuator below 2000 meters above seal level.
Options: When installing the actuator above 2000 meters above seal level,
please contact us.
Installation height
Standard: -25℃~ +70℃。
Low temperature type: -40℃~ +70℃。
Ultralow temperature type: -60℃~ +50℃。
Ex-proof: -20℃~ +40℃。
Temperature
Standard: Self-adjusting potentiometer.
Option: Feedback 4~20mA analog position indication signal.
Feedback signal
It is natural that the temperature of the motor surface reach
or exceed 80℃when working, do not touch the motor for
fear scald.

Tianjin Beifang Valve Actuator Co.,Ltd. 920 series Instruction Manual
5
• “BF” logo is cast in the apparent position of each electric actuator.
• Each electric actuator has a nameplate printed with company name, ”BF”
logo, “CE” mark and so on. Content of nameplate includes:
•Type code
•Main code
•Wiring diagram No.
•Maximum torque
•Output speed
•Allowable thrust: Used for stem nut connection
•Supply voltage
•Rate power of motor
•Rate current of motor
•Degree of protection provided by enclosure
•Manufacturing No.
•Manufacturing date
•Address
Content nameplate of ex-proof product also includes:
•Ex-proof degree of protection provide by enclosure
•Certification No.
Only manufacturing No. in each product is a basis of accurately tracing
product. Please keep it well.
3. Identifiers



Tianjin Beifang Valve Actuator Co.,Ltd. 920 series Instruction Manual
6
4.Structure
21
20
19
18
17
16
15
14
13
No.
Wiring-box cover
Main house
Conduit entries
Body of handwheel
Clutch
Driven shaft component
Driven sleeve
Output flange
Cover
Name
Terminal strips
Position indicator
Torque switch
Limit switch
counter
Torque transmission component
Limit transmission component
Hand /auto lever component
Handwheel component
Screwed plug for injection grease hole
Worm shaft component
Motor
Name
11
7
5
6
12
10
9
8
4
3
2
1
No.
4.1 Size 9201 1
2
3
4
5
6
7
8
9
10
11
13
14
15
17
16
18
19
20
21
12

Tianjin Beifang Valve Actuator Co.,Ltd. 920 series Instruction Manual
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1
4.2 Sizes 9202 ～9205
23
4
5
9
10
6
14
13
12
16
17
18
20
21
19
22
23
7
8
23
22
21
20
19
18
17
16
15
14
13
No.
Wiring-box cover
Housing cover component
Hand /auto lever component
Main house
Screwed plug for injection grease hole
Handwheel shaft
Handwheel component
Worm shaft component
Conduit entries
Driven shaft component
Driven sleeve
Name
Output flange
Cover
Terminal strips
Position indicator
Torque switch
Limit switch
counter
Torque transmission component
Limit transmission component
Clutch
Hand /auto component
Motor
Name
11
7
5
6
12
10
9
8
4
3
2
1
No.
11
15

Tianjin Beifang Valve Actuator Co.,Ltd. 920 series Instruction Manual
8
5. Transport and storage
5.1 Transport •It is necessary to use solid package during transportation.
•When lifting the electric actuator by hoist, please attach ropes or hook
to enclosure. Do not attach ropes or hooks to handwheel, hand/auto
lever or wiring-box.
•If the electric actuator has been mounted to the gearbox, please
attach ropes or hooks to the gearbox rather than to the electric
actuator for the purpose of lifting by hoist.
•If the electric actuator has been mounted to the valve, please attach
ropes or hooks to the valve rather than to the electric actuator for the
purpose of lifting by hoist.
•Do not stand under the dangling electric actuator.
5.2 storage • Units should be stored in the well ventilated, dry, non-corrosive room.
• Units should be placed on bracket or the dry wooden flooring.
• If necessary, units are covered with dust guard.
• Long-term storage (more than 6 months).
• To avoid corrosion, wipe handwheel shaft, driven shaft, driven sleeve and
mounting surface with anti-rust oil.
• Check the units for rust every 6 months. If there is any rust, please treat
again for rust prevention.
6. Lubrication
-25 ~ +120℃Temperature range
Lithium soap thickened mineral oilPrincipal component
• There are O-rings or lip seal between the main house and its contacting
portion. The main house is fully filled with 00# lithium grease to lubricate the
worm shaft, worm gear, gears, bearings and so on.
• No seal can remain absolutely tight at all time, therefore, it is not unusual to
find a very small amount of weeping around shaft sealing-especially during
long periods of idleness such as long-term storage. Once the equipment
has begun operating, this phenomenon will automatically disappear.
• It is not need to refresh the lubricating grease periodically. If the lubricant is
deficient in quantity or its quality has changed, please infuse the lubricating
grease with the same trademark or the same performance from the
injecting grease hole.
00# gear lubricating grease used by the standard units


Tianjin Beifang Valve Actuator Co.,Ltd. 920 series Instruction Manual
9
7. Installation
7.1 Installing handwheel For easier transport, the handwheels of sizes 9202~9205 are placed
separately, so please mount the handwheel on the manual shaft, before
doing manual operation.
• Handwheel of size 9201 is directly mounted on the product.
• Design of 920 series ensure man power can drive manual operation, no
need to use the force rod.
7.2 Installation to valves or gearboxes
• Apply for the valve stems which can rotate and not lift: Driven sleeve has
two types of structure-one with hole and keyway and one with jaw.
1.Check whether each mating surface of joint flange fits the valve’s.
2.Check whether dimensions of input shaft and key or jaw in the valve or
gearbox fit the electric actuator’s.
3.Clean up grease on the mating surface of joint flange.
4.When connecting with shaft and key, a little of greases is smeared on the
shaft
5.When installing the electric actuator, tighten the screws after ensuring
mating of the joint flange and shaft or jaw is good.
• Without removing joint flange #1, drive sleeve #2 can be directly removed.
Therefore install the drive sleeve to the shaft or jaw of the valve ,and then
connect the electric actuator with the flange of the valve.
• When the valve stem is shaft with key, the valve stem must have a step for
prevent drive sleeve from moving.
• After installation is complete, check and repair the damage coating .
Material performance level of the parts which connect the electric actuator
with the valve or gear is 8.8 class. Yield strength is 628N/mm² .
7.2.1 Plug sleeve connection
•Warning: If electric actuators are installed in the hazardous gas area,
must check whether the ex-proof degree on the nameplate is
appropriate.
• In the hazardous area, it is prohibited that conductive body and thermal
conductor contact with the electric actuator. Except special allowable work,
the units must be cut off power, remove from the hazardous area for repair
or maintenance.
Driven sleeve with
hole and keyway
Driven sleeve with
jaw
1
2
1
2


Tianjin Beifang Valve Actuator Co.,Ltd. 920 series Instruction Manual
10
• Apply for the valve stem which can lift and not rotate: 920 series apply
independent thrust plate component to bear thrust. The stem nut is supplied
with a pilot hole or blind hole. Before installing the actuator to the valve,
users need to machine the stem nut according to the dimension of the valve
stem.
Machining the stem nut:
1.Put down the electric actuator, and then loosen the screw fixed seam
allowance #4.
2.In turn take out seam allowance with O-rings and stem nut with bearings
from the thrust plate component.
3.Take out O-rings #1 and thrust bearings #2 in sequence from the stem nut.
Notice: Do not damage to O-ring.
4.Machine the stem nut to make sure the thread must match the thread of
the valve tem；
5.Clean up foreign matter on the stem nut, assemble thrust bearings with
some lithium grease, and then assemble the O-rings.
6.Re-insert the assembled stem nut and seam allowance into the actuator,
and then screw.
Connecting to the valve：
1.Check whether the flange of the actuator fit one of the valve.
2.Clean up the grease on the mounting surface of joint flange.
3.Smear some grease on the thread of the stem nut or the valve stem.
4.Install the actuator to the valve stem, engage manual operation, and turn
handwheel to make the stem nut mesh with the valve stem.
5.Continue to turn handwheel until the flange of the actuator touch the flang
of the valve, turn the hanwheel two laps again to make the flanges fit
closely, and then screw the bolts to fix the actuator and the valve.
• When disassembling and assembling, do not damage the O-rings.
• The flange of the valve can bear enough thrust.
• After installation is complete, check and repair the damage coating.
Material performance level of the parts which connect the electric actuator
with the valve or gear is 8.8 class. Yield strength is 628N/mm².
7.2.2 Stem nut connection
1
2
3
2
1
4


Tianjin Beifang Valve Actuator Co.,Ltd. 920 series Instruction Manual
11
If you do not obey the warning ,will cause serious injury or property damage.
• Electrical connection must be done by the qualified personal。
• Before wiring, please comply with the relevant provisions of the clause 。
• There are the wiring diagram and <920 series electric actuators for multi-
turn application instruction manual> in the sealed plastic bag with the unit.
You can also directly ask for them fromTianjin Beifang Valve Actuator Co.,
Ltd by offering Manufacturing No in the nameplate, or you can get them
from www.tj-beifang.com。
8. Electrical connection
8.1 Before wiring Check whether current type, voltage and frequency of the power fit the motor
parameters in the nameplate.
8.2 Wring
• If the cable joint is not used, remove it, and block the conduit entry with the
plug. The openings are 2-G3/4″for the standard products
• To ensure IP on the nameplate, the cable joints must be compatible with
the cable.
• Check whether the PE wire of the cable is connected with the . If do not
connect the PE wire, electrocution can occur.
Electrical component in the unite with high voltage, work on
the electrical system or equipment must only be carried out by
an electrician who possess operating certificate or by
specially instructed personnel under the control and
supervision of such an electrician and in accordance with the
applicable electrical engineering rules.
1.Shut off all incoming power.
2.Open the cover, keep the compartment of the main house clean and dry.
3.Check the stickup code to ensure that it coincides with the code of the
wiring diagram supplied with the unit and connect wires properly
according to the wiring diagram
4.Conduit entries in the main house provide two openings for routing the
pilot cable and the dynamic cable. Seal the opening after wiring.
5.Manual operate the unit to keep the valve in the intermediate position,
turn power on and check the rotating direction of the valve, then cut off
power supply. If the direction is wrong, interchange any two leads of the
three phase.
When finish installation, connect wires according to the wiring diagram
supplied with the unite.

Tianjin Beifang Valve Actuator Co.,Ltd. 920 series Instruction Manual
12
9.Manual operation
• When adjusting the product or trail run of the product, the manual operation
can be used.
• If the motor or power is failure, the manual operation is used.
Carry out manual operation:
1.After the motor operation, the handwheel is separated from the output
component automatically. If need the handwheel to operate, please move
the hand/auto lever to the direction of arrow on the lever and gently turn the
handle until the handwheel and the clutch are in full engagement.
2.After loosening the hand/auto lever, the manual operation is engaged.
3.Turn the handwheel according to need. If close the valve, turn the
handwheel clockwise, and the output shaft will be turn clockwise to close
the valve.
The hand/auto lever can be locked in the motor mode by a padlock to
prevent the local manual operation. Our company does not supply the
padlock.
• During the motor operation, pull and hold the hand/auto lever to make the
electric drive disengage imminently.
• No need to use the force rod for manual operation.
If the hand/auto switch failure occurs, do not move the lever forcibly.
Turn the handwheel until the hand/auto switch succeed.
The hand/auto lever
for sizes 9202~9205
The hand/auto lever
for size 9201



Stop manual operation：
When opening or closing the valve, the motor operation will be engaged
automatically, and the manual operation will stop.
During the period of the motor operation, the handwheel will not rotate.
Do not move the hand/auto lever forcibly after finishing the manual
operation. Energization of the motor will make the clutch
automatically out of jointing with handwheel, and re-engage power
operation.

Tianjin Beifang Valve Actuator Co.,Ltd. 920 series Instruction Manual
13
10.Setting the torque switch
Open
12
Close 12
1.Clear the adjustment direction of the torque: White mark is “Open”, and
black mark is “Close”.
2.Loosen lock screw #1 on the torque dial #2 to adjust torque.
3.Turn the torque dial #2 to the required output torque. When turning the
indicator to “Min”, reduce the torque value. When turning the indicator to
“Max”, increase the torque value.
4.Tighten lock screw #1 on the torque dial #2.
5.Applying power, motor operate the valve to check whether the torque is
meet the requirement when the torque switch automatically cut off the
power. If not, repeat the above process to reset.
The torque switch is respectively designed to protect the actuator and the
valve in the direction of “open” and “close”. The switch was set at the
factory. The setting torque is equal to “Rate output torque” in the
nameplate. It is not need to reset generally.
When need to adjust the torque switch, set the torque of “open” and
“close” respectively as follow after the manufacturer agree.
When adjusting the torque, must cut off the power.
11.Setting the limit control mechanism
When the actuator first installed or re-installed, must adjust the limit
control mechanism to make the responding contacts can be accurately
operated once the valve reaches the required position.
For 920 series products, the limit control mechanism includes limit
switches used for disconnecting the power and a counter used for
memorizing the turns of the driven shaft.

• According to requirement, the limit switches of 920 series product can
be provide in up to four control positions, respectively “Full open”, “Full
close” and the middle position of “Open” and “Close” . Up to four
contacts are provided in each control position. The upside contacts on
“Full open” and “Full close” are used for cutting off the power to motor
when the valve reaches to the full open position or the full close
position, and the others are auxiliary contacts.
• Each switch is independent contact, and the contact can be wilfully
change to open or close. Adjusting method as follow:
11.1 Setting the limit switch
1.Loosen the screws #1 fastening switches.
2.Take out conductive seat #3 from switch seat #2.
3.Rotate the conductive seat for 90°, and re-insert the switch seat.
4.Tighten the screw #1.
1
2
3

Tianjin Beifang Valve Actuator Co.,Ltd. 920 series Instruction Manual
14
Adjustment process of the counter as follows:
1.Disconnect all incoming power to the unit prior to opening the cover。
2.Making the actuator in the state of manual operation, manual operates
the valve to the full open position, then turn the handwheel back for
one turn to leave a short buffer for the operation of driven shaft.
3.Push the sleeve (B), clockwise turn it, lock it in the depressed position,
and then loosen it.
4.If the upside contact is off state, turn adjusting pole (A) to opposite
direction of the arrow till the contact on the opening valve position is
on state. Then turn adjusting pole to the same direction of the arrow
till once the contact on the opening valve position just disconnect. The
adjustment finishes. (When clockwise rotating to open valve, turn
adjusting pole to opposite the direction described above, the same as
below.)
5.If the upside contact is off state, turn adjusting pole to the same
direction of the arrow till once the contact on the opening valve
position just disconnect. The adjustment is finished。
6.After adjustment of full open position finishes, counter-clockwise turn
the sleeve (B), and it will come to initial position by spring action. The
counter is well engaged if the adjusting pole mildly rotated could not
be turned, so can do the following adjustment.
7.Refer to process 3~6 to adjust other positions.
•Must cut off all incoming power to the unit prior to opening
or closing the cover.
•Check to ensure the valve is in full open position before
removing the unit from the valve.
•When finishing adjusting, the sleeve (B) must come to the
initial position. If not, the adjustment will be damaged by any
manual or motor operation.
11.2 Setting counter When the actuator first installed or re-installed, must adjust the counter to
make the responding contacts can be accurately operated once the valve
reaches the position required by user.
•Limit control mechanism is not factory set. It must be set
when the unit installs on the valve.
•After replacing the valve or reinstalling the unit, reset the
limit control mechanism prior to motor operation.
•Do not motor operate the valve without first setting the limit
control mechanism.
•The adjustment force will increase when the contact changes
from on state (or off state) to off sate (or on state), which is
normal during adjusting.
•When the counter setting is finished, the user should motor
operate the unite to ensure the limit control meet the
requirement, or reset the counter.
Counter Switch
☞
Open the
valve
Close the
valve
By observing the location of white mark on the switch, judge the
top switch contacts is the state of on or off. As shown in the left
image, the switch is on when the white marks are connected
together, and the switch is off when the white marks are
disconnected.
On state
Off state

(B)(A)

Tianjin Beifang Valve Actuator Co.,Ltd. 920 series Instruction Manual
15
• Determine the turns of driven shaft, and then select and change the
potentiometer gear #3.
• The way of changing the potentiometer gear #3 is shown below.
1.Referring to the table below, select the potentiometer gear with
corresponding mark according to the turns of driven shaft.
2.If the potentiometer gear matching the turns of driven shaft is
default, the following steps can be omitted .
3.If the potentiometer gear matching the turns of driven shaft is one
marking 2 or 3, pick out the potentiometer gear marking 2 or 3
with the unit.
4.Loosen the screw #5 (no need to screw out completely), loose the
platen #4, replace the potentiometer gear required, and confirm
the gears meshing completely.
5.Adjust well the position of platen, and tighten the screw #5
1
2
• Adjusting the sleeve #1.
1.Move the sleeve #1 hard up and down to make the number of hole
#2 completely exposed correspond with the turns of driven shaft,
referring to the table below, and the bottom hole only can be
exposed half of hole (refer to the position of A in the left image).
Turn the sleeve #1 to conform it rotates freely.
2.Operating the electric actuator to the full close position, clockwise
turn the sleeve #1 until it does not rotate, and then measure the
resistance between terminal 2 and terminal in the wiring diagram.
The resistance valve should be between0~10Ω.
3.Gently move the sleeve up to make the bottom half hole exposed
fully (refer to the position of B in the left image ), and then turn the
sleeve to confirm it does not rotate. The adjustment is finished.
3
45
6 7 8
A
B
When the sleeve can not be moved up and down, operate the
actuator to close or open for a short trip, and then try to move the
sleeve up and down. If not, operate the actuator in reverse for a
smaller trip than last operation.

12.Setting the position indicator
•The position indicator must be set after finishing the setting
of counter.


920 series electric actuator provide mechanical valve position indicator,
and a potentiometer is supplied for remote indication.
The consumer may use a voltmeter according to the relevant wiring
diagram to remotely read the valve position indication signal or
accept 4~20mADC analog position indication signal output by the
transmitter VPT2 or VPT4 purchased at the time of order.
Adjustment process of mechanical valve position indicator as follows:
Poten
tiomet
er
gear
Number of the hole completely exposed on the sleeve
Turns of driven
shaft
331~49090~134.524.5~36.56.6~101.8~2.7Mark 3
217~33159~9016~24.54.3~6.61.2~1.8Mark 2
134.5~21736.5~5910~162.7~4.31~1.2Default
43210

Tianjin Beifang Valve Actuator Co.,Ltd. 920 series Instruction Manual
16
Full close position
of the valve
Full open position
of the valve
• Adjusting the dials #6 and #7:
1.Motor operates the valve to the full close position, and loosen
screw #8.
2.Adjust the dial #6 to the full close position of the valve as shown in
the figure, and tighten the screw #8.
3. Motor operates the valve to the full open position, hold on dial #6,
and then loosen screw #8.
4.Keep dial #6 fixed, rotate dial #7 to the full open position of the
valve as shown in the figure, and tighten screw #8.
13.Installing the cover
• Clean the sealing surface of cover and main house.
• Smear a thin layer of acidic grease evenly on the sealing surface.
• Check whether O-ring is intact.
• Mount the cover。
• Engage the motor operation, check whether the indicator aims at the
mark on the dials indicating position. If not, removing the cover, re-
adjust the dials indicating position.
• Symmetrically tighten the fastening screws.
After installation is completed, check the surface paint of the
electric actuator, and repair the damage coating to prevent
corrosion.

Operating the valve to close, the dials rotate clockwise. Operating
the valve to open, the dials rotate counterclockwise.
