Siemens OCM III User manual

Instruction Manual November 2005
OCM III
open channel

© Siemens Milltronics Process Instruments Inc. 2005
Safety Guidelines: Warning notices must be observed to ensure personal safety as well as that of
others, and to protect the product and the connected equipment. These warning notices are
accompanied by a clarification of the level of caution to be observed.
Qualified Personnel: This device/system may only be set up and operated in conjunction with this
manual. Qualified personnel are only authorized to install and operate this equipment in accordance with
established safety practices and standards.
Unit Repair and Excluded Liability:
• The user is responsible for all changes and repairs made to the device by the user or the user’s
agent.
• All new components are to be provided by Siemens Milltronics Process Instruments Inc.
• Restrict repair to faulty components only.
• Do not reuse faulty components.
Warning: This product can only function properly and safely if it is correctly transported, stored,
installed, set up, operated, and maintained.
Note: Always use product in accordance with specifications.
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Instruments Inc. 2005. All Rights Reserved Disclaimer of Liability
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Inc. will not be responsible for the contents of partial or
whole reproductions of either bound or electronic
versions.
While we have verified the contents of this
manual for agreement with the
instrumentation described, variations
remain possible. Thus we cannot
guarantee full agreement. The contents of
this manual are regularly reviewed and
corrections are included in subsequent
editions. We welcome all suggestions for
improvement.
Technical data subject to change.
MILLTRONICS®is a registered trademark of Siemens Milltronics Process Instruments Inc.
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Siemens Milltronics Process Instruments Inc.
1954 Technology Drive, P.O. Box 4225
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TABLE OF CONTENTS
TITLE PAGE
ABOUT THIS ...
About This Manual 7
About the OCM-3 7
SPECIFICATIONS 9
Programmer 10
Transducer 11
Temperature Sensor 11
Cabling 11
Communication Software 11
INSTALLATION
Installing the OCM-3 13
Outline and Mounting 13
OCM-3 Layout 14
System Diagram 15
Installing the Transducer 16
Installing the Temperature Sensor 16
mA Output 17
Relays 17
Synchronization 18
Power Connections 19
Installing the Memory Back-up Battery 20
Communicating Via Computer 20
Installing the Programmer 20
7ML19985AB01 OCM III 3

START UP
General 21
Keypad 21
Legend 22
Initial Start Up 22
Fundamental Checks 25
OPERATION
Memory 27
Security 27
Units 27
Flow Calculation 28
Display 28
Damping 29
Relays 30
mA Output 30
Fail-Safe 31
Flow rate and Totalizing 31
Logging 32
Blanking 34
Temperature 34
Time and Date 34
Emulation Mode 35
Reset 35
Flow Velocity Input 36
Auxiliary Head Input 36
DC Output 37
Diagnostic Aids 37
7ML19985AB01 OCM III 4

‘D’ PARAMETER LISTING 39
‘F’ PARAMETER LISTING 41
‘P’ PARAMETER LISTING 43
‘U’ PARAMETERS FOR P3 PRIMARY ELEMENT 51
Simple Exponential Devices, P3 = 0 53
BS-3680 Rectangular Flume, P3 = 1 58
BS-3680 Round Nose Horizontal Crest Weir, P3 = 2 60
BS-3680 Trapezoidal Flume, P3 = 3 62
BS-3680 U - Flume, P3 = 4 64
BS-3680 Finite Crest Weir, P3 = 5 66
BS-3680 Thin Plate Rectangular Weir, P3 = 6 68
BS-3680 Thin Plate V-Notch Weir, P3 = 7 70
Rectangular Weir (Contracted), P3 = 8 72
Round Pipe, P3 = 9 74
Palmer-Bowlus Flume, P3 = 10 76
H - Flume, P3 = 11 78
Universal Head vs. Flow, P3 =12 80
Rectangular Area x Velocity, P3 = 13 82
Trapezoidal Area x Velocity, P3 =14 84
Modified Trapezoidal Area x Velocity, P3 = 15 86
U Channel Area x Velocity, P3 = 16 88
Circular Area x Velocity, P3 = 17 90
Gull-Wing Area x Velocity, P3 = 18 92
Egg-Shaped Area x Velocity, P3 =19 94
Universal Area x Velocity, P3 = 20 96
APPENDICES
Maintenance 99
Error Codes 100
Communications 101
7ML19985AB01 OCM III 5

7ML19985AB01 OCM III 6

ABOUT THIS ...
ABOUT THIS MANUAL
Although the OCM-3 is very ‘approachable’ due its dialogue capabilities and intuitive
operation, the user should be familiar with this manual. This manual provides the user
with the necessary information required to install, start up and operate the OCM-3.
As the OCM-3 prompts the user with specific messages in a step-by-step fashion
during programming, the Start Up section serves essentially to compliment the
OCM-3. Start Up provides the user with instructions on the use of the programmer
and an overview of the programming requirements.
The ‘D’, ‘F’, ‘P’ and ‘U’ parameters listed in the Parameters section provide a quick
reference of the available programming and display parameters and their options. The
‘U’ parameter listing also provides mathematical and graphical details as a reference
to assist the user in programming the OCM-3 to the primary element being used. The
user is urged to rely on the manufacturer’s specification for obtaining and identifying
the primary element to which the OCM-3 is being applied.
In short,
If you want to know about Read
the product About This . . .
Specifications
getting started Installation
Start Up
how it works Operation
Parameters
Appendices
ABOUT THE OCM-3
The OCM-3 is to be used only in the manner
outlined in this instruction manual.
The Milltronics OCM-3, Open Channel Meter, is an electronic instrument designed to
measure flow in open channels. It is housed in a polycarbonate enclosure and comes
with a removable programmer. As a system, it is used in conjunction with a remote
ultrasonic transducer (or auxiliary head measurement device) and a temperature
sensor.
The OCM-3 transmits a pulse signal to the transducer which is then emitted as
ultrasonic pulses. The pulses echo off the water surface and are then sensed by the
transducer. The time for a pulse to echo back from the water surface is temperature
compensated and converted into a measurement of head.
7ML19985AB01 OCM III 7

The OCM-3 converts the head measurement into flow rate, but also provides a
velocity sensor input for applications where a flow velocity measurement is required to
perform the flow calculation. The flow rate is totalized and stored in a comprehensive
data log to provide detailed flow analysis.
Programming of the OCM-3 allows the operator to select the flow calculation specific
to the primary measuring device (flume, weir or pipe). Special emphasis has been
placed on providing the most accurate flow calculations possible. To this end, specific
routines have been written to comply with the British Standards Institute’s
Specifications BS-3680. These routines calculate correction factors taking into
account second order effects such as approach velocity and boundary layer. In the
event that flow measurement is not covered by one of the flow calculations provided,
the OCM-3 can be programmed for flow measurement using one of the universal
flow calculations.
The OCM-3 provides serial communication for remote programming, data log retrieval
and print out for devices such as computers, PLCs and printers. Milltronics provides a
standard utilities software package for OCM-3 programming, remote display and data
retrieval. However, the user is not limited to the software provided. The user can
develop his own software program to perform tasks suited to his specific needs.
The OCM-3 features:
✓multi field illuminated LCD, for ‘Flow and Total’ and ‘Relay Status’ display
✓0 or 4 to 20 mA output
✓three multipurpose relays, including remote totalization
✓1 to 24 months data log, subject to logging rate
✓extensive serial communication, including RS-232
✓removable infra-red programmer
✓AC and DC (bi-current) operation.
7ML19985AB01 OCM III 8

SPECIFICATIONS
Power: » dc supply: » 9 to 30 V DC, 8 W max and / or
» ac supply: » 100/115/200/230 V ac ±15%, 50/60 Hz,
20 VA max
Environmental: » location » indoor /outdoor
» altitude: » 2000 m max
» ambient temperature » – 20 to 50 °C (–5 to 122 °F)
» relative humidity » suitable for outdoor (Type 4X/Nema 4X
IP65 enclosure)
» installation category » II
» pollution degree » 4
Memory
back-up: » 3 V lithium battery (NEDA 5003LC or equivalent)
» operating life 1 year
» ‘SuperCap’ capacitor for back-up
during battery replacement
Range: » 0.3 m min to 1.2 m max ( 1 to 4 ft)
0.6 m min to 3 m max (2 to 10 ft)
Resolution: » 0.2 mm (0.007")
Accuracy: » ±1 mm/m, calculated error less than 0.02%
Temperature
Compensation: » external sensor to compensate over
the operating range
Programming: » via supplied programmer and
communication link
Inputs: » velocity sensor and
auxiliary head » range: » 0 to 10 V dc
» resolution: » 2.7 mV
Outputs: » transducer drive: » 44 Khz, 400 Vpp pulses of 0.1 msec typical
duration at a 100 msec typical repetition rate.
» instrumentation: » range: 0-20 or 4-20 mA
» resolution: 5 uA
» maximum loading: 1 KΩ
7ML19985AB01 OCM III 9

» isolation: 300 V ac continuous
» relays: » 3 alarm/control relays
» 1 form ’C’ SPDT contact per relay, rated at
5 A at 250 V ac non-inductive or 30 V dc
» dc output: » +24 V dc
» 20 mA average to 200 mA at 1/10 duty
cycle max
Communication: » RS-232 or ±20 mA bipolar current loop,300,
600, 1200, 2400, 4800, 9600 or 19200 baud
Data Logs: » variable rate on 1, 5, 15, 30 or 60 min or 24 hr
» 31 days minimum/2 years maximum
Display: » illuminated liquid crystal 5 x 7 dot matrix
display with 2 lines of 40 characters each
Enclosure: »Type 4X / NEMA 4X / IP65
» 209 mm W x 285 mm H x 92 mm D
(8.2" W x 11.2" H x 3.6" D)
» polycarbonate
Weight: » 2.3 Kg (5.1 lb)
Approvals: » CE *, FM, CSA NRTL/C
» MCERTS Class 1 open channel flow device with environment
operation limits at 35 °C (95 °F) at 93% relative humidity
SIRA MC 050058/01
PROGRAMMER
Enclosure: » general purpose
» 67 mm W x 100 mm H x 25 mm D
(2.6" W x 4" H x 1" D)
» ABS plastic
Operating Temperature: » –20 to 50 °C (–5 to 122 °F)
7ML19985AB01 OCM III 10

Battery: » 9 V (ANSI / NEDA 1604, PP3 or equivalent) or
3V lithium battery
TRANSDUCER
Model: » XRS-5*
Refer to associated Transducer manual.
TEMPERATURE SENSOR
Model: » TS-2, LTS-1 or LTS-1C
Refer to associated Temperature Sensor manual.
CABLING
Transducer: » RG-62U coaxial
» maximum separation 183 m (600 ft)
» must be run in grounded metal conduit
mA Output: » Belden 8760 or equivalent
Synchronisation: » Belden 8760
Temperature Sensor: » Belden 8760, 1 pair shielded/twisted,
18 AWG or equivalent
» maximum separation 183 m (600 ft)
» can be run in conduit with transducer cable
Communication: » RS-232: » Belden 8770, 3 wire shielded, 24 AWG
or equivalent
» maximum separation 15 m (50 ft)
» Bipolar Current: » Belden 9552, 2 pair shielded/twisted,
18 AWG or equivalent
» maximum separation 1,500 m (5,000 ft)
*Note: The XRS-5 must be used with the TS-2 external temperature sensor when
operating with the OCM-3.
Velocity Input: » Belden 8760 or equivalent
7ML19985AB01 OCM III 11

Auxiliary Input: » Belden 8760 or equivalent
24 V Output: » Belden 8760
COMMUNICATION SOFTWARE
Milltronics Utilities Software on standard PC floppy disk for DOS 3.1 and up.
7ML19985AB01 OCM III 12

INSTALLATION
Installation shall only be performed by qualified personnel
and in accordance with local governing regulations.
INSTALLING THE OCM-3
The OCM-3 should be mounted in a clean, dry area that is: within the ambient
temperature range and suitable for the specified enclosure. The front cover should be
accessible for programming and viewing.
It is advisable to keep the OCM-3 away from high voltage or current runs, contactors
and SCR control drives.
Do not mount the OCM-3 in direct sunlight without the use of a sun shield.
This product is susceptible to electrostatic shock.
Follow proper grounding procedures.
209 mm
(8.2")
lid screws
(6 places)
106 mm
(4.2")
91 mm
(3.6")
16 mm
(0.6")
285 mm
(11.2")
267 mm
(10.5")
programmer
lid
suitable location for
conduit entrances
mounting holes
(accessed under
lid 4.3 mm (0.17")
dia.,4 places
enclosure
customer mounting
screw
Milltronics reccomends using a punch for making
holes in enclosure. Use suitable cable glands to
maintain ingress rating.
172 mm
(6.8")
OUTLINE AND MOUNTING
Non metallic enclosure does not provide grounding between connections.
Use grounding type bushings and jumpers.
13 OCM III 7ML19985AB01

OCM-3 LAYOUT
board A
board B
display
board
Hazardous voltage present on transducer terminals during operation.
dc terminals shall be supplied from SELV source in accordance
with IEC 1010-1 Annex H.
Relay contact terminals are for use with equipment having no accessible
live parts and wiring having insulation suitable for at least 250 V.
The maximum allowable working voltage between
adjacent relay contacts shall be 250 V.
All field wiring must have insulation suitable for at least 250 V.
14 OCM III 7ML19985AB01

SYSTEM DIAGRAM
98/03/05
OCM-3 Milltronics transducer,
see Specifications
Milltronics TS-2,
temperature sensor
customer device
customer alarm,
pump or control
device
customer device
customer device
customer device
Milltronics CVCC
mA output
relay output
auxiliary input
velocity input
RS-232
Maximum system capability. Not all components or their maximum quantity
may be required.
bi-polar current
(Milltronics communication)
15 OCM III 7ML19985AB01

INSTALLING THE TRANSDUCER
INSTALLING THE TEMPERATURE SENSOR
Max cable run 183 m (600 ft) of
RG-62U or equivalent. Cable must
be run in a grounded metal conduit
with no other cabling (except
Temp. Sensor cable).
Ground shield at OCM-3 only.
Insulate shield at junctions to
prevent inadvertent grounding.
Basic Wiring – Temperature Sensor
Basic Wiring – Transducer
Maximum cable run 183 m (600 ft) of
Beldon 8760, 1 pair shielded/twisted,
18 AWG or equivalent.
Temperature sensor cable can be
run with the transducer cable in a
grounded metal conduit.
Ground shield at OCM-3 only.
In order to compensate for uniform
temperature change in the air
between the transducer and the flow
surface, the temperature sensor
must be connected to the OCM-3.
Hazardous voltage present on transducer terminals during operation.
Note: When using the XRS-5 transducer with the OCM-3, use the TS-2 external
temperature sensor. The internal temperature sensor in the XRS-5 cannot be used.
16 OCM III 7ML19985AB01

mA OUTPUT
RELAYS
All relays are certified for use in equipment where the short circuit capacity of the
circuits in which they are connected is limited by fuses having ratings not exceeding
the rating of the relays.
isolated 0 or 4 to 20 mA output (P26) into 1 KΩload maximum.
Wiring should conform to standard instrumentation practices.
Ground shield at OCM-3 only.
relays shown in de-energized state,
contacts rated at 5 A at 250 V
non-inductive.
n.c. com n.o. n.c. com n.o. n.c. com n.o.
17 OCM III 7ML19985AB01

SYNCHRONIZATION
Where two to a maximum of twelve transducers will be sharing a common conduit the
OCM-3s should be synchronized. In order to synchronize OCM-3s:
» remove jumper J1 on board A on all but one OCM-3
» interconnect the SYNC terminal (TB1-20) of all OCM-3s. Insure that
all OCM-3s share a common ground (TB1-34).
18 OCM III 7ML19985AB01

POWER CONNECTIONS
The OCM-3 power supply accepts 100, 115, 200 or 230 V ac per switch SW1
(board B) selection and 9 to 30 V dc.
The OCM-3 operates either under ac or dc power, or both ac and dc live
simultaneously. If both ac and dc power are live, the OCM-3 normally draws power
from the ac supply. In the event that the ac supply fails, the OCM-3 then draws power
from the dc supply.
The equipment must be protected by a 15 A fuse or
circuit breaker in the building installation.
A circuit breaker or switch in the building installation, marked
as the disconnect switch, shall be in close proximity to
the equipment and within easy reach of the operator.
9 to 30 Volt
dc input
negative dc input (TB1-24) is
tied to ground (TB1-34)
DC POWER
dc terminals shall be supplied from SELV source in accordance
with IEC 1010-1 Annex H.
100/115/200/230 V ac, 50/60 Hz,
select voltage via switch on board B
AC POWER
* switch shown in
‘OFF’ position,
select appropriate
voltage.
*
19 OCM III 7ML19985AB01

INSTALLING THE MEMORY BACK-UP BATTERY
The memory battery, B1 (see Specifications) should be replaced yearly to insure
memory back up during lengthy power outages. An on board capacitor provides
one hour of memory retention in order to preserve the memory while the battery
is being changed.
COMMUNICATING VIA COMPUTER
Refer to Communication.
INSTALLING THE PROGRAMMER
To program the OCM-3 via the Programmer, it must be placed into the front cover
recess of the OCM-3. The back of the Programmer has a magnetic plate which will
hold the programmer in place. It can be removed when programming is completed.
Do not install the memory back-up
battery until the OCM-3 is to be used.
The unit is supplied with one battery
package. Remove the battery from
the package and insert it into the
battery socket.
Refer to Operation \ Memory.
Disconnect power before installing or replacing the battery.
20 OCM III 7ML19985AB01