Cadillac® CMAG Magnetic Flow Meter

(for Wastewater)

Favored choice for water-based flow applications

The Cadillac® CMAG magnetic flow meter 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 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.



Product Summary

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.


Cadillac®  CMAG Magnetic Flow Meter Applications

The Cadillac® CMAG magnetic flow meter is a totalizing device that is capable of measuring liquids of all types and consistency while providing an obstruction free flow path. This meter can be applied effectively for the following purposes:

  • Data Source for energy management system, DCS, district-wide systems.
  • Cooling tower Water flow.
  • Potable Water flow.
  • General industrial and domestic Water flow.
  • Industrial and domestic Wastewater flow.
  • Aquifer injection Water flow.
  • Process Water flow.
  • Water based Coolant flow.
  • Water based Slurry flow.
  • Reclamation Water flow.
  • Clarifier Water flow.

Cadillac®  CMAG Magnetic Meter Features

The Cadillac® CMAG pumped condensate flow meter is the number one choice due to accuracy, rangeability, longevity, modern electronics, and independent flow profile.


+/-0.25% of the reading for liquids with 1.5 pipe diameters of piping straight run up and downstream from the meter’s centerline.

+/- 0.50% of reading for liquids without any piping straight run at all


Typically 300 to 1 turndown or better at +/- 0.25% accuracy,  400 to1 turndown at +/ 0.50% accuracy, 500 to 1 turndown at +/- 1.00% accuracy With seasonal heating/cooling load variation, the need for a large turndown is essential. Cadillac® magnetic flow meters will accurately measure all load requirements with proper sizing.


Mean time between failure (MTBF) of 40 years. With no moving parts and through simple robust design the meter has unmeasured life expectancy.

Modern Electronics

All Meters are equipped with electronics capable of registering locally, remotely or interfacing with an energy management system. With Modbus and Profibus communications now available the electronics now provide a true digital output to any energy management system.

Flow Profile Independent

The flow meter does not require traditional flow conditioning or piping straight run. .. Piping straight run from the centerline of the meter is 1.5 pipe diameters, which is essentially the mating flange face of the piping system in CMAG meters under 6” in size.


Cadillac®  CMAG Magnetic Flow Meter – Principles of Operation

To understand the operation principles for Cadillac® CMAG Magnetic Flow Meter, it’s important to define Faraday’s law. It states that when you move a conductor perpendicular through a magnetic field, a voltage will be induced proportional to the velocity of the conductor. A magnetic field is created by a set of coils which are encapsulated and rigidly retained in the meter flow tube and, when a conductive liquid moves through that magnetic field, a pair of electrodes measures the voltage induced by the movement of the liquid. The measurement is independent of conductivity changes in the liquid as long as it remains above the minimum threshold of 3 uS/cm2.

The relationship between the liquid velocity and the induced voltage is expressed in a meter K-factor. The meter K-factor is unique to each and every meter and is documented during a NIST traceable flow test completed prior to shipment. With the K-factor established a highly accurate volumetric flow is calculated by multiplying the cross sectional area of the flow tube by the measured liquid velocity. This volumetric relationship can then be converted to various engineering units and the flow meter converter can then retransmit this information with a 4-20 mA current signal and/or conditioned pulse. An optional integral LCD Indicator/Totalizer is available to locally display and totalize in whatever engineering units preferred.


Cadillac®  CMAG Magnetic Meter – Dimensions

The Cadillac® CMAG magnetic meter’s dimensions are outlined below. Please reference the letters with the chart for each meter size.



Meter Size 0.5″ 1.0″ 1.5″ 2.0″ 3.0″ 4.0″
“L1” (face to face) 5.51″ 6.30″ 6.69″ 7.09″ 9.06″ 9.45″
“L3” (top to bottom) 9.88″ 10.71″ 11.34″ 12.20″ 13.66″ 14.45″
“L2” (centerline to top) 7.99″ 8.23″ 8.58″ 9.13″ 10.04″ 10.31″
ANSI Class 150 lb
14 lbs 18 lbs 23 lbs 29 lbs 45 lbs 58 lbs
Meter Size 6.0″ 8.0″ 10.0″ 12.0″ 14.0″ 16.0″ 18.0″
L1 10.24″ 11.81″ 13.78″ 15.75″ 17.72″ 19.69″ 21.65″
L3 16.73″ 18.70″ 21.06″ 23.15″ 24.37″ 26.65″ 28.74″
L2 11.22″ 12.20″ 13.18″ 14.37″ 14.72″ 15.63″ 16.54″
ANSI Class 150 lb
86 lbs 128 lbs 265 lbs 315 lbs 375 lbs 475 lbs 650 lbs


Cadillac®  CMAG Magnetic Flow Meter – General Specifications

Cadillac®  CMAG Magnetic Flow Meter includes the following specifications:

  • Meter will consist of a full-bore body with encapsulated and rigidly retained set of coils.
  • Meter available with remote or integral electronics with indication and totalization.
  • Meter operates at +/- 0.25% accuracy without flow profiling or piping straight run exceeding 1.5 pipe diameters from meter centerline.
  • Meter available with pulse and analog (4-20 mA) outputs.
  • Meter will provide instantaneous and totalized flow available at local indicator or remotely through outputs.
  • Meter measures flow using Faraday’s law (Induce voltage is directly proportional to the velocity of the conductive liquid)
  • Meter K-factor is stable and not influenced by external piping or mounting orientation.
  • Meter will have uniform magnetic field flux distribution eliminating piping straight run and flow profiling.
  • Meter will measure fluids with conductivity greater than or equal to 3.0 uS/cm2
  • Meter fluid temperature range:
    • (14°F to 176°F) with integral or remote electronics and EPDM liner.
    • (14°F to 248°F) with integral or remote electronics and PFA liner.
    • (14°F to 248°F) with integral electronics and Ceramic liner.
    • (14°F to 356°F) with remote electronics and Ceramic liner.
  • Meter flow tube operating pressure rating: ANSI 150 or ANSI 300
  • Meter power supply: 100-240 VAC, 50/60 Hz (Optional 24Vdc). Power consumption approximately 14 watts
  • Meter will have empty pipe detection and contact (DO) available for alarming.


Cadillac®  CMAG Magnetic Flow Meter – Installation

Traditional Installation requirements have been redefined with the Cadillac® CMAG magnetic condensate flow meter. Employing coil and plate shaping techniques the Cadillac® meter provides a uniform magnetic field within the entire flow tube, allowing the meter to measure and sample voltage uniformly from the entire flow tube area. In addition, the electronics provide high frequency DC square wave signal generation and flow signal sampling, enabling fast response to turbulent or tumbling flow conditions that may occur without a fully developed flow profile.

In practice, this means the Cadillac® magnetic flow meters do not require traditional piping straight run or flow conditioning, and may be installed next to elbows, tees, valves, etc. without any effect in meter accuracy or stability.

In comparison, the straight pipe run requirements for all other magnetic flow meters are as follows:

Downstream of the meter:

  • Expander (2-5) diameters
  • Tee – (2-5) diameters
  • Elbow – (2-5) diameters
  • Valves – (2-10) diameters

Upstream of the meter:

  • Expander – (10) diameters
  • Tees – (5) diameters
  • Elbow (5) diameters
  • Valves – (10) diameters

Unlike other technologies such as turbine, variable orifice, pitot tube, orifice plates/DP cells, and Vortex, including the Cadillac® Vortex flow meter, magnetic flow meters do not have a low flow cutoff, essentially allowing the meter to read to zero while still provide an accurate measurement. With such a wide flow range capability for the technology, most applications can be addressed with meters at full line size.


CMAG Model Code

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