No Moving Parts
The solid-state measurement design contains no mechanical measuring components that obstruct the flow path or wear during normal operation.
CMAG Magnetic Flow Meter for Wastewater
The CMAG employs a revolutionary tube design. The CMAG is most effective where flow profiling is unavailable. The CMAG opens up new and retrofit installations to huge savings in design, layout or reconstruction/modification.
Or talk to someone right away. Dial (888) 556-3913
The Cadillac® CMAG magnetic flow meter for wastewater is capable of measuring liquids of all types and consistency while providing an obstruction free flow path. Due to its unique flow tube/coil design, it is particularly suitable for new or retrofit into hot and chilled water systems where high accuracy is required and/or limited flow profiling or piping straight run is available. Employing a unique coil winding pattern and containment/focusing plates the Cadillac® magnetic flow meter for wastewater does not require any flow profiling or piping straight run while still meeting the stated meter accuracy (+/-0.25% of rate). In any liquid measuring system the Cadillac® magnetic flow meter is the number one technology choice due to Cadillac’s® accuracy, linearity, reliability and rangeability.
Like many other flow meters, the Cadillac® magnetic flow meter is a velocity measuring device which computes flow by multiplying the effective cross sectional area of the flow meter with the detected fluid velocity. The meter has no moving parts and consists of a meter body with encapsulated coils, electrodes and an amplifier assembly. It detects velocity by measuring an induced voltage that is developed by moving the conductive fluid through a magnetic field.
The Hot/Chilled Energy Water Flow Meter of Choice
With its limited flow profiling or piping straight run requirement the CMAG makes an excellent choice for both Hot and Chilled water energy applications. The CMAG design will allow easy retrofit into tight mechanical rooms and basements, without affecting the measurement accuracy. In addition, the CMAG has the industry best turn-down at 300:1, which is ideal for the modulating flow rates common today with energy saving variable speed pumping systems.
The Water and Wastewater Industry Standard
With its limited flow profiling or piping straight run requirement the CMAG makes an excellent choice for both water and wastewater applications. With line sizes common above 16 inches the CMAG allows new designs to eliminate long piping straight runs in order to get an accurate and reliable flow measurement. This significantly reduces the footprint of a building or other areas where the flow meters would be mounted. With increased wetted material selections most Water, including potable, applications have also looked to magnetic flow meters as the preferred choice, especially in applications requiring analog (rate) or pulse (totalized) outputs.
Technical Product Guide
CMAG Magnetic Flow Meter for Wastewater
Explore the CMAG’s operating principle, wastewater applications, performance, flow ranges, construction, electronics, installation requirements, dimensions and configuration options.
±0.25%
Stated accuracy with the specified 1.5D piping arrangement
300:1
Typical turndown at the stated ±0.25% accuracy
Full-Bore Design
Obstruction-free measurement with no moving parts
≥3 µS/cm
Published minimum fluid conductivity
Product Overview
Full-Bore Magnetic Flow Measurement for Wastewater
The Cadillac CMAG is a rate and totalizing magnetic flow meter for electrically conductive liquids. Its full-bore flow tube provides an obstruction-free flow path suitable for wastewater, clean water, reclamation water, water-based slurries and other conductive industrial liquids.
The meter uses a shaped coil-winding pattern with containment and focusing plates to create a controlled magnetic field across the flow tube. This reduces dependence on a fully developed flow profile and makes the CMAG particularly useful in compact installations and retrofit projects where conventional straight-pipe requirements would consume substantial space.
Rate and Total Flow
Instantaneous flow rate and totalized volume can be displayed locally or transmitted to a control, monitoring or energy-management system.
Compact Installation
Reduced flow-profile requirements can simplify layouts where elbows, tees, valves or other piping constraints are close to the meter.
Wide Flow Range
Published turndown reaches 300:1 at the stated ±0.25% accuracy and up to 500:1 at ±1.00% under the specified installation conditions.
Applications
Water, Wastewater and Conductive Process Liquids
The CMAG can measure conductive liquids of varied consistency while maintaining a clear, full-bore flow path. This makes it suitable for municipal, commercial and industrial systems that require reliable flow rate, totalized volume or control-system data.
Wastewater Flow
Rate monitoring, process control and totalized-volume measurement for industrial and domestic wastewater systems.
Reclamation Water
Measurement for reclaimed-water distribution, reuse systems and plant-wide water accounting.
Clarifier Water
Flow data for clarifier operation, process balancing and control feedback within water-treatment facilities.
Water-Based Slurries
Obstruction-free measurement of conductive mixtures containing suspended material, subject to application and material review.
Aquifer Injection Water
Flow-rate monitoring and totalized-volume measurement for conductive water entering aquifer-injection systems.
Process and Cooling Water
Operational measurement and data input for process control, cooling-tower systems, energy management and distributed controls.
Measurement Technology
How the CMAG Measures Conductive Liquid Flow
The CMAG operates according to Faraday’s law of electromagnetic induction. When an electrical conductor moves perpendicularly through a magnetic field, it produces a voltage proportional to the conductor’s velocity.
Inside the meter, encapsulated coils generate a magnetic field across the full-bore flow tube. As the conductive liquid moves through that field, a pair of electrodes measures the induced voltage. The converter uses this signal to determine liquid velocity.
Volumetric flow is calculated by combining the measured velocity with the known cross-sectional area of the flow tube. The resulting value can be displayed, totalized or retransmitted in the required engineering units.
Magnetic Field
Encapsulated coils generate a controlled magnetic field across the meter’s flow tube.
Induced Voltage
Conductive liquid moving through the field produces a voltage detected by the electrodes.
Velocity Calculation
The measured voltage is converted into liquid velocity using the calibrated meter relationship.
Flow Output
The converter calculates volumetric flow and provides rate, totalization and system outputs.
Meter Performance
Accuracy, Turndown and Low-Flow Capability
The CMAG combines high stated accuracy with a wide operating range. The applicable accuracy depends on the available straight piping, meter sizing, turndown and installation conditions.
| Operating Condition | Published Piping or Turndown Condition | Stated Accuracy |
|---|---|---|
| Standard high-accuracy range | 1.5 pipe diameters from the meter centerline upstream and downstream, through 300:1 turndown | ±0.25% of rate |
| Zero straight run | No upstream or downstream straight piping | ±0.50% of reading |
| Extended turndown | From 300:1 through 400:1 with the stated 1.5D piping arrangement | ±0.50% of rate |
| Maximum published turndown | From 400:1 through 500:1 with the stated 1.5D piping arrangement | ±1.00% of rate |
High-Accuracy Turndown
The published standard operating range reaches 300:1 while retaining the stated ±0.25% accuracy under the specified piping arrangement.
Maximum Published Range
The CMAG can extend through 500:1 turndown at the published ±1.00% accuracy under the stated installation conditions.
Low-Flow Measurement
Unlike several mechanical and differential-pressure technologies, magnetic flow measurement does not require a mechanical low-flow cutoff.
General Specifications
Construction, Electronics and Output Options
The CMAG combines a full-bore magnetic flow tube with integral or remote electronics. Available indication, totalization, communication and alarm functions allow the meter to operate as a local instrument or as part of a larger process-control or monitoring system.
| Specification | Published Configuration or Capability |
|---|---|
| Meter body | Full-bore body with an encapsulated and rigidly retained set of electromagnetic coils |
| Electronics | Integral or remote converter with indication and totalization options |
| Analog output | 4–20 mA current signal for instantaneous flow rate |
| Pulse output | Conditioned pulse output for totalized-flow transmission |
| Digital communications | Modbus and Profibus communication options |
| Power supply | 100–240 VAC, 50/60 Hz; optional 24 VDC supply |
| Power consumption | Approximately 14 watts |
| Diagnostics | Empty-pipe detection with a digital or contact output available for alarming |
| Pressure classes | ANSI Class 150 or ANSI Class 300 |
| Fluid conductivity | 3.0 µS/cm or greater |
| Calibration | Meter-specific NIST-traceable flow test and documented K-factor |
Published Liner Temperature Limits
| Liner | Electronics Arrangement | Fluid Temperature Range |
|---|---|---|
| EPDM | Integral or remote | 14°F to 176°F |
| PFA | Integral or remote | 14°F to 248°F |
| Ceramic | Integral | 14°F to 248°F |
| Ceramic | Remote | 14°F to 356°F |
Preliminary Sizing
Published CMAG Liquid Flow Ranges
The published brochure lists the following minimum and maximum configurable 4–20 mA output spans for liquid service. These values provide an initial sizing reference rather than a final meter selection.
Final sizing should account for the expected minimum, normal and maximum flow rates, fluid velocity, conductivity, suspended solids, pressure, temperature and the required measurement accuracy.
| Nominal Meter Size | Minimum Volumetric Span | Maximum Volumetric Span |
|---|---|---|
| ½ inch | 0.00–0.250 GPM | 0.00–25 GPM |
| 1 inch | 0.00–0.750 GPM | 0.00–75 GPM |
| 1½ inch | 0.00–1.750 GPM | 0.00–175 GPM |
| 2 inch | 0.00–3.000 GPM | 0.00–300 GPM |
| 3 inch | 0.00–8.000 GPM | 0.00–800 GPM |
| 4 inch | 0.00–12.50 GPM | 0.00–1,250 GPM |
| 6 inch | 0.00–25.00 GPM | 0.00–2,500 GPM |
| 8 inch | 0.00–50.00 GPM | 0.00–5,000 GPM |
| 10 inch | 0.00–75.00 GPM | 0.00–7,500 GPM |
Published ranges reproduced from the supplied CMAG general-information brochure. Consult Cadillac Meter for sizes or ranges not shown.
Information Required for Final Sizing
Flow Conditions
Minimum, normal and maximum flow rates, including seasonal or process variations.
Fluid Properties
Conductivity, chemistry, suspended solids, abrasiveness and expected temperature.
Piping Conditions
Line size, pressure class, orientation, available space and nearby disturbances.
Instrumentation
Required accuracy, display arrangement, power, outputs, communications and alarm functions.
Installation
Reduced Straight-Pipe Requirements
Conventional magnetic flow meters frequently require substantial lengths of straight piping to establish an acceptable flow profile. This can increase the footprint and cost of a wastewater installation, particularly on larger lines or in retrofit projects.
The CMAG uses coil and containment-plate shaping to produce a controlled magnetic field across the flow tube. High-frequency signal generation and sampling help the meter respond to turbulent or tumbling flow conditions, reducing its dependence on conventional flow profiling.
±0.25% Accuracy
Use 1.5 pipe diameters from the meter centerline upstream and downstream under the published high-accuracy arrangement.
±0.50% Accuracy
The published performance guidance permits operation with no upstream or downstream straight piping at the stated ±0.50% accuracy.
Compact Retrofit Layouts
Reduced straight-run requirements can limit pipework modification and preserve space near existing elbows, tees and valves.
Piping Requirements
Meter Orientation and Full-Pipe Operation
The CMAG flow tube must remain completely full during measurement. Partially filled piping, trapped air or an unsuitable electrode orientation can produce unstable or inaccurate readings even when the available straight-pipe length is acceptable.
Gravity-flow applications require a piping arrangement that maintains a wet leg or equivalent positive full-pipe condition. Vertical installations should normally carry liquid upward through the meter so that entrained air can move through the line rather than collect in the measuring tube.
Installation Checklist
Maintain a Full Flow Tube
Position the meter where the flow tube remains full during startup, normal operation and low-flow conditions.
Prevent Air Accumulation
Avoid high points and piping arrangements where air can collect inside the flow tube or pass intermittently across the electrodes.
Control Solids Deposition
Choose an orientation that reduces the likelihood of settled solids coating or blanketing the measuring electrodes.
Provide a Wet Leg
Use a wet-leg arrangement in gravity systems so the meter cannot drain or operate with a partially filled flow tube.
Ground the Meter Correctly
Install the specified grounding rings and follow the converter’s grounding and electrical-installation instructions.
Preserve Service Access
Allow sufficient clearance for viewing, wiring, inspection and future removal of the converter or complete meter.
Physical Data
CMAG Meter Dimensions
The following dimensions provide preliminary planning information. Obtain a certified dimensional drawing for the exact meter size, body style, flange class, liner and converter arrangement before finalizing pipework, supports or equipment clearances.
ANSI Class 150 Flanged Meter Dimensions
| Meter Size | L1: Face to Face | L2: Centerline to Top | L3: Top to Bottom |
|---|---|---|---|
| ½ inch | 5.51 inches | 7.99 inches | 9.88 inches |
| 1 inch | 6.30 inches | 8.23 inches | 10.71 inches |
| 1½ inch | 6.69 inches | 8.58 inches | 11.34 inches |
| 2 inch | 7.09 inches | 9.13 inches | 12.20 inches |
| 3 inch | 9.06 inches | 10.04 inches | 13.66 inches |
| 4 inch | 9.45 inches | 10.31 inches | 14.45 inches |
| 6 inch | 10.24 inches | 11.22 inches | 16.73 inches |
| 8 inch | 11.81 inches | 12.20 inches | 18.70 inches |
| 10 inch | 13.78 inches | 13.18 inches | 21.06 inches |
| 12 inch | 15.75 inches | 14.37 inches | 23.15 inches |
| 14 inch | 17.72 inches | 14.72 inches | 24.37 inches |
| 16 inch | 19.69 inches | 15.63 inches | 26.65 inches |
| 18 inch | 21.65 inches | 16.54 inches | 28.74 inches |
Wafer-Body Dimensions
| Meter Size | L1 | L2 | D1 | Published Weight |
|---|---|---|---|---|
| ½ inch | 2.76 inches | 9.33 inches | 1.93 inches | 17 lb |
| 1 inch | 3.15 inches | 8.90 inches | 2.60 inches | 21 lb |
| 1½ inch | 3.94 inches | 9.80 inches | 3.35 inches | 25 lb |
| 2 inch | 4.33 inches | 10.43 inches | 4.02 inches | 29 lb |
| 3 inch | 4.33 inches | 11.46 inches | 5.00 inches | 35 lb |
| 4 inch | 4.72 inches | 12.72 inches | 6.26 inches | 40 lb |
Meter Configuration
CMAG Model-Code Selection Guidance
A CMAG model is configured from the nominal meter size, converter arrangement, body style, flange rating, electrode material, liner material, grounding-ring material and any required electrical or approval options.
The following information explains the published selection structure but should not be used to construct an orderable part number without the current factory model-code sheet and application review.
| Selection Field | Published Options |
|---|---|
| Nominal size | ½, 1, 1½, 2, 3, 4, 6, 8, 10, 12 and 14 inches. Consult Cadillac Meter for larger sizes. |
| Converter | Integral converter with indicator and totalizer, or a remotely mounted converter |
| Body style | Wafer body with ceramic liner through 4 inches, or flanged body |
| Flange rating | ANSI Class 150 or ANSI Class 300 |
| Electrode material | 316L stainless steel, Hastelloy C or another application-specific material |
| Liner material | PTFE/PFA, polyurethane, EPDM or ceramic |
| Grounding-ring material | 316 stainless steel, Hastelloy C or another specified material |
| Power option | Optional 24 VDC power supply |
| Approval option | FM approval option appears in the legacy model-code structure; confirm current availability and applicability |
Information to Include with a Quote Request
Process Information
Fluid description, conductivity, suspended solids, chemical composition and coating or abrasion potential.
Hydraulic Conditions
Minimum, normal and maximum flow, line size, operating pressure and confirmation that the pipe remains full.
Mechanical Requirements
Temperature, flange class, orientation, installation space and nearby piping disturbances.
Electrical Requirements
Power supply, local display, output signals, communications, alarm functions and remote-converter cable length.
Frequently Asked Questions
CMAG Wastewater Flow Meter FAQ
What liquids can the CMAG measure?
The CMAG measures electrically conductive liquids, including clean water, wastewater, reclamation water, water-based slurries and many conductive industrial process liquids. The published minimum conductivity is 3.0 µS/cm.
Can it measure nonconductive liquids?
No. Electromagnetic measurement requires a conductive liquid. Petroleum oils, many solvents and other nonconductive fluids are not suitable for a magnetic flow meter.
Does the CMAG require straight pipe?
The published guidance states ±0.25% accuracy with 1.5 pipe diameters from the meter centerline upstream and downstream. It states ±0.50% accuracy with no straight run. Confirm the arrangement for the actual disturbances and required accuracy.
Must the pipe remain full?
Yes. The complete flow tube must remain filled with liquid. Gravity systems may require a wet leg or another piping arrangement that prevents the meter from draining or operating partially full.
Can it handle suspended solids?
The full-bore design can be suitable for conductive liquids containing suspended material. Solids loading, abrasiveness, coating potential, velocity and material compatibility must still be reviewed for the application.
What outputs are available?
Published options include 4–20 mA analog output, conditioned pulse, Modbus and Profibus. Local rate indication and totalization are also available with the appropriate converter configuration.
Is a remote converter available?
Yes. The CMAG can be configured with integral or remote electronics. Remote mounting may be appropriate for accessibility, environmental conditions or higher-temperature ceramic-lined applications.
What information is needed for selection?
Provide the fluid composition, conductivity, solids, minimum and maximum flow, line size, pressure, temperature, flange requirement, installation orientation, nearby disturbances and required electrical outputs.
Selection and Specification Support
Discuss Your CMAG Wastewater Application
Cadillac Meter can review the fluid, flow range, materials, installation constraints, required accuracy, electronics and output requirements before confirming the appropriate CMAG configuration.
Process
Fluid, conductivity, solids and chemical compatibility
Hydraulics
Minimum, normal and maximum flow, pressure and full-pipe condition
Installation
Line size, orientation, available space and nearby disturbances
Instrumentation
Display, power, outputs, communications and alarm requirements
Certified drawings, current model codes and Cadillac Meter’s application review govern the meter supplied for the project.