Page 95
UNIVERSAL AREA X VELOCITY, P3 = 20
Arbitrary area is typically used when the primary element and/or its flow do not fit any of the primary elements covered by P3. There is no user difference between absolute and ratiometric calculations P4.
The flow curve is characterized by entering the head (Aeven) and area (Aodd) ordinates for the number of data points (n, 4 to 16) over the flow range. The first point (A0,A1) generally being at 0 head and the last point (A2n-2,A2n-1) generally being at maximum head .
‘U’ parameters required * | ‘U’ parameters calculated ** |
U0 = number of data points (n, 4 to 16) | U1 = area (h) |
Aeven = head | |
Aodd = area | |
*obtain from manufacturer’s specifications.
**calculated by OCM-3. May be viewed by accessing ‘U’ parameter.
e.g. typical open channel | transducer * |
|
*The transducer must be above the maximum head by at least the blanking value, P47.
Contents
Open channel
Contact Smpi Technical Publications at the following address
Unit Repair and Excluded Liability
Table of Contents
Operation
Start UP
General Keypad Initial Start Up Fundamental Checks
Appendices
Maintenance Error Codes 100 Communications 101 7ML19985AB01
OCM
If you want to know about Read Product
About this
Short
OCM
IP65 enclosure
Specifications
» range 20 or 4-20 mA » resolution
» 20 to 50 C -5 to 122 F
» CE *, FM, CSA NRTL/C
Programmer
Cabling
Temperature Sensor
Transducer
Output » Belden
Communication Software
Auxiliary Input
Outline and Mounting
Installation
Installing the OCM-3
OCM-3 Layout
Customer device
System Diagram
OCM-3
Ground shield at OCM-3 only
Installing the Transducer
Installing the Temperature Sensor
Ground shield at OCM-3 only Basic Wiring Temperature Sensor
Relays
MA Output
Synchronization
DC Power
Power Connections
AC Power
Communicating VIA Computer
Installing the Memory BACK-UP Battery
Installing the Programmer
Disconnect power before installing or replacing the battery
Keypad
Start UP
General
English
Initial Start UP
OCM-3 is asking which language you prefer to communicate
Language
F13 auto zero calibration 160 Completed 7ML19985AB01
P0 language English P1 dimensional units Centimeters
F5 ddmmyyyy date October 12
1141
24-hr. time
114100 Enter new time
Fundamental Checks
OCM
Units
Operation
Memory
Security
= constant
Flow Calculation
Display
Absolute vs. ratiometric
Damping
For battery operation, set display lighting to off or auto
» P6 * flow rate
For battery operation, have relays energizing on alarm
Example For relay
» 20 mA
Flow rate
FAIL-SAFE
Flow Rate and Totalizing
Capacity
Logging
Viewing the data log
Time and Date
Temperature
Blanking
Reset
Emulation Mode
As normal 7ML19985AB01
Flow Velocity Input
Auxiliary Head Input
Voltage Input Current Input
100% head 4 m, enter 5 m
Diagnostic Aids
DC Output
Nominal target range
Security access required
‘D’ Parameter Listing
Velocity
OCM
Keypad to mA output
Enter security code Emulation mode
‘F’ Parameter Listing
OCM
= centimetres
‘P’ Parameter Listing
Linear Velocity
= imperial million gallons per day
Flowrate Volume
= absolute = ratiometric Flow rate units
Gallons
OCM
= 4-20 mA = 0-20 mA 7ML19985AB01
OCM
OCM
Units
Fixed
Variable condition
OCM
‘U’ Parameters for P3 Primary Element
OCM
= constant factor U1 = head
U0 = exponent U1 = k factor P4 = 0 only
Reference
Typical Weir Profiles
Typical SHARP-CRESTED Weirs
Khafagi Venturi
Typical Parshall Flume
Typical Leopold Lagco
‘U’ parameters required ‘U’ parameters calculated
BS-3680 Rectangular Flume
= crest width = Cv = crest height = Cd = crest length = a
BS-3680 Round Nose Horizontal Crest Weir
¤ Refer to Operation \ Flow Calculation 7ML19985AB01
Cv = velocity coefficient
BS-3680 Trapezoidal Flume
BS-3680 U-Flume, P3 =
BS-3680 U-FLUME
= head H and p applied to C
= crest width = C = crest height = Cp = crest length
BS-3680 Finite Crest Weir
= crest width He = effective head h + Kh = head Kh = 1 mm
= Ce x 2⁄3 ⎯⎯√2⎯g x be x he1.5 Where q = flow rate
= approach width = Ce = crest width = K b = crest height
= gravitational acceleration
BS-3680 Thin Plate Rectangular Weir
U0 = notch angle Alpha U1 = Ce
BS-3680 Thin Plate V-NOTCH Weir
U0 = crest width b
Rectangular Weir Contracted
= hydraulic radius = slope of hydraulic gradient
Based on the Manning Formula
Round Pipe
U0 = maximum flume width, hmax
PALMER-BOWLUS Flume
U0 = maximum listed head, hmax
Flume
U0 = number of data points n, 4 to
Universal Head vs FLOW, P3 =
Flow, point A19
Flow, point A13 Head, point A14
Flow, point A15 Head, point A16
Flow, point A17 Head, point A18
U0 = channel width B U1 = area h
Rectangular Area X Velocity
= head, cm = flow velocity, cm/sec
Trapezoidal Area X Velocity
= channel top width, cm = head, cm = channel base width, cm
= B b/d Where q = flow rate, l/s
For h ≥ d
Modified Trapezoidal Area X Velocity
U0 = base diameter D U1 = area h
Channel Area x Velocity
U0 = conduit diameter U1 = area h
Circular Area X Velocity
GULL-WING Area X VELOCITY, P3 =
Gull Wing Area X Velocity
EGG-SHAPED Area X VELOCITY, P3 =
EGG-SHAPED Area X Velocity
Typical open channel
Universal Area X VELOCITY, P3 =
A10 =
Universal Area X Velocity
Area Head
OCM
Maintenance
Error Codes
Serial printer
Customer’s
Computer
102
Protocol for the OCM-3 is as follows Baud rate
Refer to Cvcc Instruction
DB-9 connector
DB-25 connector
Bipolar Current
104
Date
P35 = 7, print interval set for 7 minutes
105
Utilities Software Programmer Remote OCM-3 programming
Remote OCM-3 display Local display
106
107
Typical OCM-3
Display value
00.000000 99.12399.123000 7ML19985AB01
Response
# = 0 through Content of P5
109
Start data log down load
Stop data log down load
Computer Telephone lines Remote modem
DB-25 connector 7ML19985AB01
Standard modem
Cable
111
Establishing Communication
Connect
112
Ending Communication
Rev