PACEline CMC Adaptable Piezoelectric Measurement Chain PACEline CMC Adaptable Piezoelectric Measurement Chain | HBM

CMC Series Piezoelectric Measurement Chains for Capacities ranging from 5 kN to 120 kN

Piezoelectric measurement chains of the CMC series are used in various industrial production tasks and reliably convert the forces they measure into a 0 to 10 V signal. They are calibrated throughout, which means that the measurement amplifier doesn’t have to be adjusted and the relationship between the output signal in volts and the force measurement in newtons is clearly documented in the accompanying documents.

Typical for the piezoelectric principle, the sensors have a wide measurement range and measure large and small forces reliably – even under a high initial load. The measurement chains, based on CFT variations with a 5 kN or 20 kN capacity are calibrated at 100% and at 20% of the nominal force, while all other CMC measurement chains have calibrations at 1%, 10% and 100% of their nominal force. The measurement ranges can be switched via a digital input on the charge amplifier; zeroing is triggered just as easily.

All piezoelectric force measurement chains in the CMC series consist of a pre-stressed and calibrated sensor, a charge cable and a charge amplifier. The components can be freely combined and allow the measurement chain to ideally adapt to the respective measurement task at hand.

Reliable and suitable for industrial use

  • Low drift
  • Insensitive to EMC interference
  • Stainless steel materials, IP65 degree of protection

Long-term reliable measurement results in industrial environments.

Easy integration

  • Flange connection on both sides, pre-stressing not necessary
  • Standard dimensions and connections
  • Calibrated as a measurement chain
  • Practical accessories are available

Easily fits into new and existing structures without calibration.

Wide measuring range

  • Very good linearity due to excellent mechanical quality
  • Small forces can be measured even under large preloads
  • Calibrated in two or three measuring ranges depending on the nominal force of the sensor

Ideal for multi-step processes. Magnifying function available (by switching the measurement range), that is, amplification can be increased by a factor of 5 if required.

Configuration support: How to put together the K-CMC measurement chain for specific applications?

The measurement chain consists of four components and is supplied as a whole:

  1. Sensor
  2. Charge cable
  3. Charge amplifier
  4. Test protocol

Calibration results for the sensor, the charge amplifier as well as the combination of both, that is, the entire measurement chain, are included. Since the relationship between the force (N) and the output signal (V) is documented, the subsequent components can be easily adjusted.

Apart from the geometry, the total force acting on the sensor is critical. This includes the force intended to be measured as well as preloads irrelevant for the measurement caused, for example, by tools exerting force on the sensor. Load peaks occurring due to incorrect operation or system errors, and which should not be measured, also have to be considered for determining the nominal force of the sensor.

The maximum bending moment and possible shear force of the application should not be neglected either.

The maximum loads can be found in the data sheet.

The measurement range of the charge amplifier is determined by the force to be measured and can be calculated as follows:

Minimum measurement range of the charge amplifier = force to be measured in N * sensor sensitivity

Nominal force sensor Typical sensitivity
5 kN 7.7 pC/N
20 kN 7.7 pC/N
25 kN 7.4 pC/N
50 kN 4.1 pC/N
70 kN 4.1 pC/N
120 kN 4    pC/N



  • You need to monitor a process force of max. 30 000 N. A CFT+/50kN is chosen for this application. The sensor sensitivity is 4.1 pC/N.
  • This results in a load of 30,000 N · 4.1 pC/N = 123,000 pC. You select the next larger device, that is, the CMA158, with a measurement range of 158,000 pC. At 30,000 N an output signal of 123,000/158,000 = X/0, that is, 7.78 V occurs.
  • The following order code applies: K-CMC-50k0-3m0-158N0

Despite the changed structure of the order numbers, CMC models already in use can be replaced with perfect equivalents at the same price.

The table shows the old order numbers along with their new counterparts. In this configuration, the charge amplifier is matched to the maximum nominal force of the respective sensor.

Former order number New order number (identical measuring chain)
1-CMC/5KN K-CMC-05k0-3m0-039N5
1-CMC/20KN K-CMC-20k0-3m0-158N0
1-CMC/50KN K-CMC-50k0-3m0-210N0
1-CMC/70KN K-CMC-70k0-3m0-287N0
1-CMC/120KN K-CMC-120k-3m0-482N0


Tips & tricks

  • The cable length has no influence on the behaviour of the measurement chain and should be selected according to requirements.
  • The accuracy of a larger sensor is the same as that of smaller models. If in doubt, choose a sensor with a higher nominal force.
  • The accompanying documents contain the calibration result for the entire measurement chain (with Newton as input variable and Volt as output variable). The sensitivity is also given.

Extensive accessories available, please refer to the data sheet:

  • Cable for connection with the following electronics: 1-KAB168 
  • Coupling for cable extension

PACEline Accessories