Oval Smart EX DELTA II Series User manual

1
Ins. No. D-582-3-E
Separately-mounted
preamp with totalizer
Vortex Flowmeter
Smart EX DELTAⅡ
Totalizer provided
Less Indicator
Separately-mounted sensor
Hottap type
Every OVAL Smart EX DELTAⅡis fabricated and shipped from our factory under stringent quality
control. In order to maintain its design performance throughout its life, this manual offers the
operator the necessary installation, operation and maintenance information. Be well familiar with
these instructions before you place the meter in service and keep this manual for ready reference.
（Insertion type, xed）
（Retractable, hottap type）

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CONTENTS
1. BEFORE YOU BEGIN ............................................................................................................ 5
1.1 Confirming the Specifications................................................................................................ 5
1.2 Transit Considerations........................................................................................................... 5
1.3 Storage Considerations......................................................................................................... 5
2. OPERATING CONDITIONS.................................................................................................. 5
3. GENERAL ................................................................................................................................ 6
4. COMPONENT NAMES AND FUNCTIONS ....................................................................... 6
5. PIPING INSTRUCTIONS ....................................................................................................... 9
5.1 Standard Piping Conditions................................................................................................... 9
5.2 Pipes to be Used .................................................................................................................. 10
5.3 Location of Pressure Gage and Thermometer Taps............................................................. 10
5.4 Pulsation............................................................................................................................... 10
5.5 Prevention of Cavitation (liquid service) ............................................................................... 10
5.6 Prevention of Excessive Flowrate ........................................................................................ 11
5.7 Prevention of Slug Flow ....................................................................................................... 11
5.8 Keep the Pipe Filled with Fluid ............................................................................................. 11
5.9 Bypass Line.......................................................................................................................... 11
6. INSTALLATION ....................................................................................................................... 12
6.1 Installation Locations............................................................................................................ 12
6.2 Physical Orientation .............................................................................................................. 12
6.3 Installation Procedure, Fixed Type ........................................................................................ 13
6.3.1 Typical Orientation.......................................................................................................... 13
6.3.2 Installation Procedure......................................................................................................13
6.4 Installation Pro, Hottap Type ................................................................................................. 14
6.4.1 Part Names .................................................................................................................... 14
6.4.2 Installation Procedure......................................................................................................15
6.4.3 Preamplifier Orientation................................................................................................... 16
6.5 Lagging Work ....................................................................................................................... 16
6.6 Ambient Temperature ............................................................................................................ 17
6.7 Partially Filled Pipe ................................................................................................................ 17
6.8 Working Stage and Hoist (hottap type)................................................................................. 17
6.9 Drive Unit Removal of Hottap Type .......................................................................................18
6.10 How to Change Preamplifier Orientation.............................................................................19
6.11 How to Change Display View Angle of Totalizer ................................................................. 20
6.12 Separately-mounted Preamplifier Installation......................................................................21
7. WIRING CONNECTIONS ...................................................................................................... 22
7.1 Wiring Specifications ............................................................................................................. 22
7.2 Preamplifier Terminal Identification........................................................................................ 22
7.3 Considerations on Wiring Connections .................................................................................22
7.4 Separately-mounted Preamp to Sensor Terminal Box Wiring Connections .......................... 23
7.5 Terminal Box Cover Removal ................................................................................................ 23
7.6 Hookup with Receiving Instruments ...................................................................................... 24
7.7 Diagrams Showing Typical Wiring Connections (example)................................................... 25

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8. OPERATION ............................................................................................................................ 26
8.1 Flushing the Piping Assemble ............................................................................................... 26
8.2 Operation Procedure ............................................................................................................. 26
9. FLOW SENSITIVITY ADJUSTMENT PROCEDURE....................................................... 27
9.1 Amplifier Gain ........................................................................................................................ 27
9.2 Trigger Level.......................................................................................................................... 27
10. PARAMETER SETUP .......................................................................................................... 28
11. BUILT-IN DISPLAY FUNCTIONS AND OPERATION
(totalizer equipped model) .............................................................................................. 30
11.1 Display Selection (Totalizer equipped model)......................................................................30
11.2 Total Flow Reset .................................................................................................................. 30
12. PRECAUTIONS ON PULSE TYPE.................................................................................... 31
13. PREAMPLIFIER RUN CHECK WITH SIMULATED PULSE INPUT........................... 32
13.1 Test Setup............................................................................................................................ 32
13.2 Full Scale Freq. Calculation ................................................................................................ 33
14. MAINTENANCE .................................................................................................................... 34
14.1 Disassembly and Inspection................................................................................................ 34
14.2 Disassembly and Inspection Procedure .............................................................................. 34
14.3 Preamplifier Inspection........................................................................................................ 36
14.3.1 Description of Test Pins ...............................................................................................36
14.3.2 Switch and Potentiometer Settings..............................................................................37
14.3.3 Preamplifier Block Diagram ......................................................................................... 38
14.4 Display Installation .............................................................................................................. 39
15. EXPLODED VIEW AND PARTS LIST, FIXED TYPE ..................................................... 40
16. ASSEMBLY DRAWING AND PARTS LIST, HOTTAP TYPE........................................ 42
17. GENERAL SPECIFICATIONS ........................................................................................... 44
17.1 Sensor Specifications.......................................................................................................... 44
17.2 Preamplifier Specifications .................................................................................................. 45
17.3 Nominal Meter Factors ........................................................................................................ 46
17.4 Pressure Losses.................................................................................................................. 47
18. OUTLINE DIMENSIONS ..................................................................................................... 48
18.1 EX DELTAⅡ........................................................................................................................ 48
18.2 Separate-Mount Preamplifier .............................................................................................. 50
18.3 Flow Straightener and Downstream Pipe ............................................................................ 50
19. FLAMEPROOF APPROVAL : DIMENSION OF NON-THREADED JOINTS............ 51
20. PRODUCT CODE EXPLANATION ................................................................................... 52
■NOTES ON EXPLOSION-PROOF TYPE FOR CHINA (NEPSI) ................................... 53

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CONVENTIONS
Shown in this manual are the signal words NOTE, CAUTION and
WARNING, as described in the examples below:
NOTE: Notes are separated from the general text to bring the
user's attention to important information.
CAUTION: Caution statements signal the user about hazards or
unsafe practices which could result in minor personal
injury or product or property damage.
WARNING: Warning statements signal the user about hazards or
unsafe practices which could result in severe personal
injury or death.

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DELTA FLOWMETER
OVAL Corporation MADE IN JAPAN
MODEL
SER. No.
MAX. TEMP.
MAX. PRESS
DATE
TAG. No.
METER FACTOR
FACTORD PULSE
ANALOG F.S.
AMB. TEMP.
m3/h
L/P
/P
( )
Hz
°
C
°
C
①
②
③
④
⑤
⑥
⑦
⑧
⑨
⑩
⑪
⑫
⑬
RATEDMAX.FLOW
No. Item Description No. Item Description
①Model ― ⑧ Factored Pulse Unit Not stated for analog output.
②Serial No. ― ⑨Analog F. S. Not stated for pulse output.
③Rated Max.
Flow
Max. flowrate stated in the
catalog in actual flowrate. ⑩Full Scale Freq.
Full scale frequency established.
Not stated for pulse output.
④Max. Temp. ― ⑪Ambient Temp. Max. allowable ambitent temp.
⑤Max. Pressure ― ⑫Tag No. Stated only where specified.
⑥Date ― ⑬Remarks Stated only where specified.
⑦Meter Factor Unfactored pulse unit in pulse out.
1. BEFORE YOU BEGIN
1.1 Confirming the Specifications
(1) When received, the meter should be thoroughly inspected for indication of rough handling during
transit.
(2) Product code number and ratings are stated on the meter nameplate. Make sure that the ratings
shown conform to your particular specifications.
1.2 Transit Considerations
(1) It is desirable that the meter be transported to the installation site in the shipping container used for
transit from the factory.
(2) During transportation, exercise care to avoid impact shock and rainwater.
1.3 Storage Considerations
(1) The meter can best be stored in the shipping container used for transit from the factory.
(2) The place of storage should meet the following requirements:
●Free from rain and water
●Free from vibration and impact shocks
●With least temperature and humidity variation (around 25℃and 65% R.H.)
(3) A meter that has once been placed in service for any length of time should be washed clean to remove
residue metered material completely from its inner walls before storage. Waterproofing the cable
entrance should also
be taken into consideration.
CAUTION: Unauthorized modification will invalidate the specifications.
2. OPERATING CONDITIONS
(1)This flowmeter is developed, designed, and manufactured to be used as a flowmeter for general industrial
application. Therefore, when it is used for the application where its operation is directly related to the
safety of the relevant system or where the product is important in the facilities (such as process control
and custody transfer), you are requested to secure sufficient safety including safety design, redundancy
and duplication of the process, and implementation of periodic inspection. Do not use this flowmeter in the
case where its operation and performance is directly related to human life.
(2) If this flowmeter is used under appropriate conditions, it can demonstrate its stable performance without
aging degradation of accuracy. However, malfunction or failure may occur due to various factors. Thus,
considering the operating conditions, operating status, and importance in the process, you should study
the cycle of periodic maintenance and its items of your flowmeter. In order to secure long-term and safe
use, OVAL recommends the customer to verify the soundness of the flowmeter through periodic inspection
every two years. For the details of inspection, contact our sales agent or person in charge.
(3) This flowmeter is manufactured, adjusted, and inspected to meet the conditions of use. The fluid
measured, flow range, pressure, temperature, or the like must be applied under the specified conditions.
The conditions for use are stated in the nameplate attached to the flowmeter transmitter and specification
sheet supplied with the product.
Items Stated on the Nameplate

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Features
(1) A broad flow range with high metering accuracy.
(2) The sensor isolated from the process fluid and simple meter design with no moving parts contributes
to long life.
(3) No loss of accuracy with age.
(4) A wide temperature and pressure range. Accepts most fluids, including liquids, gases and steam.
(5) Small pressure loss across the meter saves energy.
(6) Pipeline closure is not required in the event of an emergency.
(7) Output being pulses proportional to flow velocity makes totalization simple.
(8) Economy is evident when it comes to flow measurements in large diameter pipelines.
3. GENERAL
EX DELTAⅡis a vortex flowmeter, making use of a piezoelectric sensor. Behind the bluff body in a
flowing fluid, von Karman vortices form and shed proportional to the rate of flow on alternating side of the
bluff body placed perpendicular to the stream of flow. A piezoelectric sensor picks up the frequency of
these vortices, which is used for flowrate measurement.
By detecting the flowrate of a section representative of the total flow across the pipeline with a probe
inserted into the pipeline, this insertion type EX DELTAⅡmeasures the total flowrate. This type of meter
is ideally suited for flow measurements in large diameter lines.
The probe measures 50 millimeters in nominal diameter and consists of a bluff body containing a
piezoelectric sensor. Depending on the way the probe is installed in the main pipe, two types are
available: fixed and hottap. The latter design allows sensor inspection and replacement without
interrupting the process flow in the line.
This meter is full of intelligent features to review, set up, change compensated calculations, ranges,
parameters, with self diagnostics and loop test capabilities through communications with OVAL Smart
Communication Unit (Model EL2310) and general-purpose Windows PC.
4. COMPONENT NAMES AND FUNCTIONS
Refer to Figs. 4.1 and 4.2 on the next page.
①Meter Body (probe):
Consists of a measuring pipe and a vortex shedding body (bluff body). As the metered material flows,
von Karman vortices form and shed behind the bluff body.
②Sensor (vortex sensing element):
Has a built-in piezoelectric sensor. All wetted parts are made of stainless steel for maximum life
expectancy.
③Adapter (shaft assembly):
Connects the meter body with the preamplifier. To be installed on the pipeline with a flange. Also
serves to protect the sensor and dissipate heat.
④Preamplifier:
Transforms changes in electric charges generated from the sensor into an output signal representing
the flowrate. Consists of the interface board, amplifier board, isolation board, CPU board, and display.
Output comes in five types－current pulse (factored/unfctored), open collector pulse (factored/
unfctored) and analog output.
⑤Preamplifier PA25S (totalizer and digital indicator):
Physical orientation of the preamplifier is adjustable in steps of 90 deg. around the adapter axis (see
Sec. 6.10 on page 19). The display can also be oriented in steps of 90 deg. within the preamplifier
housing.

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Fig. 4.1 Component Names, Fixed Type
⑤Preamplifier PA25S（Totalizer, Digital Indicator）
8-digit LCD Totalizer
①Meter Body
（probe）
④Preamplifier
（PA25）
Flow Direction
③Adapeter
②Sensor
（vortex pickup）
Probe

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Fig. 4.2 Part Names, Hottap Type
①Meter Body
（Probe）
②Sensor
（Vortex Pickup）
Mounting
Nozzle
Flow Direction
Hold-Down Disc
Vent Valve
Handwheel
③Adapter
Gate Valve
④Preamp

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5. 配管要領
一般的な注意事項は、JIS Z 8766 『渦流量計による流量測定方法』をご参照ください。
5.1 標準配管条件 （注記） 下流側には、必ず５D以上の直管部を設けてください。
D＝Nom. Dia.
No. Remarks
1 Flow Straightener
12D
Flow
See page 50 for face-to-face
dimension.
Table 5.1 Straight Pipe Lengths Recommended by ISO-5167 D＝Nom. Dia.
No. Remarks
１Reducer
15D min.
Flow
A concentric reducer is upstream of meter.
２Elbow
23D min.
Flow
An elbow is upstream of meter.
25D min.
Flow
Two elbows are horizontally upstream of
meter.
40D min.
Flow
Two elbows are vertically upstream of meter.
３Gate Valve
Fully Open
15D min.
Flow
Fully open
A full-open gate valve is upstream of meter.
４Gate Valve,
Partially Open
50D min
Flow
Partially open
A partially open gate valve, a narrow orifice,
or something that considerably disturbs the
flow pattern is upstream of meter.
5. PIPING INSTRUCTIONS
For general consideration, see JIS Z 8766, "Flowrate Measurement Methods with Vortex Flowmeters".
5.1 Standard Piping Conditions
It is generally required that the flow pattern of a material moving into an inferential type meter be as
uniform as possible for accurate metering. Accordingly, proper flow straightening measures must be
taken when the application engineer considers installation of a DELTA meter. In applications where OVAL
straightening devices (flow straightener, and downstream pipe) are used, a straight pipe section is not
required unless otherwise specified. But if you plan to solve the flow pattern problem with a straight pipe
section alone, secure the length of a straight pipe conforming to the ISO standards given in Table 5.1
below:
(1) OVAL flow straightener combined with downstream pipe
(2) Straight pipe alone without flow straightener

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Meter Body
Flow
Direction
Gage Tap
Thermo-
meter Tap
2 to 7D
φ 6
D= Nominal dia.
Fig. 5.1
5.2 Pipes to be Used
Pipes having the inside diameter specified at the time you placed an order for this meter should be used
for upstream and downstream pipes. Otherwise, consult the factory for compatibility.
Taps for the pressure gauge and/or thermometer,
if desired, should be located downstream of
the flowmeter as illustrated in Fig. 5.1 at right.
Thermometer tap should be located on the
downstream side of pressure detection and, at the
same time, upstream of the control valve.
5.3 Location of Pressure Gauge and Thermometer Taps
5.4 Pulsation
Compressors, Roots blowers and other pulsation pressure generating sources could adversely affect
meter performance. Minimize pulsating pressures by referring to the following formula:
N <7.2 ρV2(Pa)
where N : Pulsation pressure (Pa)
ρ: Density (kg/m3)
V : Minimum velocity (m/s)
If pulsation pressure is excessive, the following measures should be taken into consideration:
①Locate the source of pulsation downstream of the meter or locate it as far from the meter as possible.
②Provide a pulsation attenuator, such as a chamber or pulsation snapper.
③Shut off valves upstream and downstream of the meter when fluid flow is interrupted (as a precaution
against erratic signal generation at zero flow).
5.5 Prevention of Cavitation (liquid service)
To prevent cavitation, line pressure should be maintained above the level calculated by the following
formula:
P≧2.60ΔP+1.25P0(MPa abs.)
where ΔP: Pressure loss (MPa) (See page 48.)
P0: Steam pressure of liquid (MPa abs.)
ρ: Density (kg/m3)
V : Flow velocity (m/s)

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Fig. 5.2
P1 P2
P1 P2
Valve
Valve
Meter
Meter
Gauge
Gauge
Flow
Direction
Flow
Direction
「Ｂ」
「Ａ」
5.6 Prevention of Excessive Flowrate
To ensure long meter life, transient flowrates
should be held below 1.6 times the meter's
maximum rating. Shown below are typical
examples in steam measurement where
excessive flow is often encountered:
Examples where meter's maximum rating is
exceeded on a momentarily basis
In steam measurement
When P1＞P2, quickly opening the valve will
result in a fluid flow at a rate dependent on the
line resistance (mainly valve port position in
"A" or meter resistance in "B"). The resultant
rate of incoming flow is the sum of downstream
pipeline volume and consumption, but if pressure
differential across the valve is great, the fluid
velocity will easily reach the sonic speed,
momentarily well in excess of meter's maximum
rating. (Such phenomenon is often experienced at
system startup or in batch operation.)
Fig. 5.3
MeterUpstream Valve Downstream Valve
Valve in Bypass Line
Flow
Direction
5.7 Prevention of Slug Flow
This meter can measure both gases and liquids, but slug flows (where gases exist in the process liquid)
will produce a loss of metering accuracy.
5.8 Keep the Pipe Filled with Process Fluid
When making a liquid measurement, ensure that the piping remains full of the process liquid. Installation
in locations where it is difficult to keep the piping filled with the process liquid, or where bubbles tend to
collect should be avoided.
5.9 Bypass Line
For maintenance and servicing purposes, it is a
good practice to provide a bypass line. Valves
upstream and downstream of the meter should be
of a design which will not disturb fluid flow pattern,
such as ball valves (full bore type), in this
arrangement (see Fig. 5.3).
For general considerations to be observed,
refer to JIS Z 8766, "Flowrate Measurement
Methods with Vortex Shedding Flowmeters".

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Fig. 6.1 Installed upside down Fig. 6.2 Cable entry pointed upward
Top
Bottom
Top
Bottom
6. INSTALLATION
6.1 Installation Locations
Select a location with ambient temperatures -10 to +80℃(or -10 to +60℃for meters configured to
explosionproof rating). Installation in such locations as described below should be avoided:
①Hardly accessible for maintenance and servicing
②Temperature change and/or vibration is excessive
③Possible immersion in water
④Corrosive atmosphere
⑤Unfit for the meter's explosionproof configuration
6.2 Physical Orientation
This meter may be installed either on a horizontal or vertical run. Avoid, however, such physical
orientation as:
①Inconvenient for inspection and maintenance ②Rainwater is ready to enter from cable entry
(if installed outdoors)
CAUTION: The hottap type requires installation in a horizontal pipeline.

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Fig. 6.4
Ｖ-Groove Mark
（Center Mark）
Bolt
Gasket
Pipe
Probe Body
Fig. 6.3
〈Horizontal Line〉〈Vertical Line〉
Preamp
Preamp Fitting
Screw
Adaptor
Flow Direction：Right→Left and Left→Right
Preamp
Flow Direction：Top→Bottom and Bottom→Top
6.3 Installation Procedure, Fixed Type
Install the meter body in the following manner:
The piping may run either horizontal or vertical. Install the meter in a position illustrated in the sketches
below.
6.3.1 Typical Orientation
6.3.2 Installation Procedure
Install the meter in the following manner:
①The meter probe body is provided with blind
caps. Be sure to remove them before you
install.
②Determine the location by the flow direction
arrow mark and the center mark (V-groove) on
the shaft assembly (102).
③Be sure to install the gasket.
(1) Do not forget to install the gasket in place
and tighten bolts.
(2) A leak test should be conducted before
commencing operation.
CAUTION:

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Fig. 6.5
Drive
Unit
Handwheel（Probe goes up or down as you turn it
in or out.）
Stud
Flow Direction
Gaskets
Cover
Short Pipe
（With Vent Valve）
Match Mark B（Indicates the probe is at the fully
raised position.）
Match Mark A（Indicates the probe is at the fully
inserted position.）
Guide
Packing Retainer
Gland Packing
Screw Axis
Gate Valve
Retaining Ring
Hold-Down Disc(Prevents noises caused by line
oscillation.)
Mounting Nozzle
Caution: Care should be taken
in the physical orientation.
Probe(Flowrate sensing assembly,consists of 2"
body, bluff body and sensor.)
6.4 Installation, Hottap Type
6.4.1 Part Names

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Fig. 6.6
Flow
Directin
Hold-Down Disc
Tapered Face Up
Arrow Mark
6.4.2 Installation Procedure
(See assembly drawing in Fig. 6.5 on page 13 and Fig. 16.1 on page 43.)
By turning in or out the handwheel, the probe of this flowmeter goes down or up and, without the need of
interrupting the line, it can be drawn out. When the meter is placed in service for measurement, the hold-
down disc is so positioned as to come in contact with the retaining ring (the guide is at match mark "A" on
the stud).
During maintenance or inspection, allow the probe to be housed completely in the short pipe (the guide is
at match mark "B" on the stud) and remove the meter from above the gate valve.
When removing or installing it, exercise care to minimize the possibility of unexpected trouble by
observing the following instructions:
(1) Install the hold-down disc in the right physical orientation.
(2) As the probe passes through the opening in the gate valve, make sure that the gate valve is in its fully
opened position when the probe is inserted, and that the probe is hoisted completely above the gate
valve when the gate valve is closed before attempting to remove or install.
(3) Be aware of the internal pressure when you remove the flowmeter. (Allow the pressure to escape
through the vent valve before attempting to remove the meter.)
(4) Directions of handwheel rotation
Clockwise rotation (viewed from top) →Probe descends.
Counterclockwise rotation (viewed from top) →Probe ascends.
Installation Instructions
(1) Install the h o l d - d own disc between the
mounting nozzle (mounting flange) and gate
valve.
・Use extra care to install the hold-down disc
in the right physical orientation at this time.
Ensure that the arrow mark on the side
of hold-down disc conforms to the actual
flow direction and that the arrow mark is on
the left hand side as viewed from the flow
direction (upstream side).
・Install a gasket on top and bottom of the
hold-down disc.
(2) Install the meter.
・Remove protective caps provided on the
sides.
・Ensure that the arrow mark on the cover
conforms to the flow direction.
・Ensure that the flanges of short pipe, gate valve and hold-down disc are flush and in line with the
periphery and the center mark (V-groove).
(3) With the gate valve fully open, insert the probe until the retaining ring comes into contact with the hold-
down disc by turning the handwheel. The guide should be at the match mark (V-groove) on the stud at
this time.
・Ensure that the vent valve is fully closed and that the fitting bolts are tight.
・In the event a leak persists through the gland packing, retighten the bolts holding the packing
retainer.

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Fig. 6.8
Fig. 6.7
Preamp Fitting
Screw Adaptor
Preamplifier
Flange Connecting
Bolt
Pipeline Lagging
Simple Lagging Work
（Split-design desirable
for ease of maintenance）
Lagging Work
Preamplifier
Cable Entry
To Probe
Display
Removal Procedure
(1) Disconnect wiring of the preamplifier.
(2) By turning the handwheel, retract the probe.
Retract it until the guide arrives at match mark "B" on the stud.
(3) Confirming that the probe has been retracted completely, fully shut off the gate valve.
(4) Taking precautions against internal pressure, carefully open the vent valve, allowing the internal
pressure to escape.
(5) Remove the flowmeter from above the gate valve.
6.4.3 Preamplifier Orientation
As viewed from the direction of flow (upstream
side), the preamplifier typically installs inclined to
the left. The cable entrance points downward. In
the standard installation, the display of a display
equipped preamplifier (PA25S) faces in the
direction of outflow (downstream side).
6.5 Lagging Work
If heat insulation is considered for the piping,
simplified lagging (without mortar finish) is
suggested for the area where the meter is
installed to facilitate disassembly and inspection.
Such consideration will simplify meter connecting
bolt removal without the need of breaking the coat
of lagging material at servicing.

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Fig. 6.9 Ambient Temperature Range
Ambient Temp.（℃）
Fluid Temp.（℃）
Nonexplosionproof
Explosionproof
Operating
Range
300
250200
150100500-30
125
-40
-20
0
20
40
60
80
6.6 Ambient Temperature
Given in Fig. 6.9 is the allowable process fluid
temperature relative to the ambient temperature.
Ensure that the ambient temperature is held
within the rating.
If there is a possibility that the ambient
temperature exceeds the allowable limit,
the following measures should be taken into
consideration.
●Avoid exposure to the direct rays of the sun.
●Separate from the piping and equipment of
elevated temperatures or provide a heat shield.
●Thermally insulate the preamplifier (in a low
temperature environment).
6.7 Partially Filled Pipe
When making measurement of a liquid, make sure the piping remains full of fluid and contains no trapped
air or gases. In applications where the existing piping conditions potentially cause a partially filled
pipeline, a purge valve should be provided.
6.8 Working Stage and Hoist (hottap type)
To facilitate hottap type DELTA meter inspection and maintenance, we recommend that a working stage
and a hoisting device are provided.

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Fig. 6.10
Option
Fig.A Fig.B Fig.C
Retract
Handwheel
Screw Axis
No. Part Name Q'ty Remarks
309 Cover 1
311 Adaptor A 1
340 Shaft Retaining Bolt 2 M12
341 Hex Nut A 2 M12
411 Connecting Stud 2
414 Hex Bolt 3 M16
415 Hex Nut 2 M16
6.9 Hottap Type Drive Unit Removal
The drive unit (retractable assembly including the handwheel and screw axis) can be separated. It is
beneficial in applications where line vibration is great, or where a single drive unit is shared by multiple
flowmeters.
①Installing the shaft fitting bolts [Fig. A]
Secure the adaptor A to the cover with shaft fitting bolts and hex nuts A. (This prevents the shaft from
being forced upward under line pressure.)
②Separating the shaft from its connection [Fig. B]
Taking off two hex nuts, turn the handwheel to extract the connecting studs from the adaptor A.
③Removing the drive unit [Fig. C]
Taking off three hex bolts, remove the drive unit. Exercise care not to bump against the preamplifier or
other components.
Drive unit removal procedure
Drive unit installation is the reverse of the removal instructions.

D-582-3-E
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Fig. 6.12
Fig. 6.11
Fig. 6.13
Fig. 6.14
Hex Socket Head
Screw
90°
※
Latch
Cover
Shield Strip
Hex Soc. Head Screw
Sensor Leads
Turn
The preamplifier can be oriented to the desired
direction in 90°steps as shown in Fig. 6.11.
NOTE: To change the orientation, hex key (JIS
B 4648), nominal size 4, is required.
The preamplifier can be rotated by
loosening its four hex socked head
screws, but be sure to disconnect
sensor leads before attempting to
rotate it.
CAUTION: Turning the preamplifier with
sens or l e ads in place may
damage the sensor.
Procedure
Refer to Section 15, "EXPLODED VIEW AND
PARTS LIST, FIXED TYPE" on pages 41 and 42.
①Turn off power.
②Remove the terminal box cover (Fig. 6.12).
NOTE: If the preamplifier is of explosionproof,
d i s e n g a g e t h e l a t c h (※) b e f o r e
removing the cover.
③Separate the shield strip (Fig. 6.13).
④Disconnect sensor leads from the terminal
block.
⑤Loosen a total of four hex socket head screws
securing the preamplifier's neck (Fig. 6.14).
⑥Turn the preamplifier to the desired direction,
exercising care not to force the sensor leads.
⑦When the preamplifier orientation has been
set, assemble in the reverse order of removal.
6.10 How to Change Preamplifier Orientation

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Fig. 6.16
Fig. 6.17
Fig. 6.15
Latch
Windowed Cover
Display Assembly
Rotatable In 90°
Step
Connector
Horizontal Run Vertical Run
If the preamplifier is equipped with local display
(indicator and totalizer), the display assembly can
be rotated to the desired direction in 90°steps
through 360°. By changing the angle of display
assembly (internal assembly), the indicator or
totalizer appears for maximum readability on a
vertical run or a horizontal run.
How to Change Display Angle
Refer to Sec. 14.4 "Display Installation" on page
40 and Sec. 15, "EXPLODED VIEW AND PARTS
LIST, FIXED TYPE" on pages 41 and 42.
NOTE: In explosionproof model, hex bar (JIS
B 4648), nom. size 3, is required to
take off the latch and change the
orientation.
WARNING:
①In the explosionproof model, remove the latch
securing the window cover (Fig. 6.16).
②Remove the window cover (Fig. 6.16).
③Loosen four screws holding the display
assembly and remove the display assembly
from its connector (Fig. 6.17).
NOTE:
④Orient the display assembly to the desired
angle, install it as far into the connector as it
will go and secure it with four screws (adjustable
in 90°steps).
NOTE: Make sure it is pushed in as far as it
will go.
⑤Install the window cover in place.
⑥The explosionproof model requires installing
the latch securely.
CAUTION: The cover must be screwed in
as far as it will go.
6.11 How to Change Indicator and Totalizer Orientation
In the case of externally powered
model, be sure to remove power
before you work.
The procedure above applies to the
separate-mount type preamplifier.