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Shown is the 1-830 axial displacement transmitter that was recently introduced by CEC Vibration Products Inc. along with its 1-828 vibration transmitter. These transmitters fill out the company’s product offerings for machine monitoring applications.

CEC Vibration Products Inc., Covina, California, U.S.A., has recently introduced its 1-828 and 1-830 displacement transmitters for radial and axial displacement applications to the company’s
monitoring system’s product line.

“These transmitters fill out our product offerings for the machine monitoring applications where we are typically found,” said Richard Rogers, national sales manager, CEC Vibration Products Inc. “The noncontact measurements are used on the slower-moving elements of the machines where shaft vibration energy may not be transferred to the bearing case. These transmitters provide a lowcost means to condition the signals provided by the eddy current probes.”

The 1-828 series of radial displacement transmitter is designed for applications on turbine generator sets, fans or blowers, motors, gearboxes and bearings. It is a single-channel unit designed to interface with major probe systems having similar specifications to the GE Bently Nevada 3300, 3300XLand 7200 series.

The linear range of operation is zero to 16 Vd.c. corresponding to a gap of 10 to 90 mils. The unit features a 4 to 20 mA output that is proportional to the peak-to-peak dynamic displacement as sensed by the probe and extension system. The probe gap and buffered dynamic signal are easily accessed via the front panel BNC connector.

Each transmitter requires a power supply input of 18 to 32 Vd.c. at 250 mA and has a maximum load resistance of 1000 ohms. The units’ scaled output range is selected at 5 or 10 mils peakto- peak displacement. Each unit has a sensitivity scale of -200 mV/mil with an accuracy of ±5% at 25°C with a temperature coefficient of ±3.5% per 38°C temperature increase from 25°C with a linearity of ±1 mil of best-fit straight line. The preferred target material is 4140 stainless steel or Incoloy 901. The operating temperature range is -40° to 66°C and relative humidity levels of 95% noncondensing.

The unit is compact, measuring just 45 x 70 x 125 mm and weighs just 283 g. It is also 35 mm DIN rail mountable and has a case made of PVC with an interior zinc overspray shielding. The terminals are tension-loaded contacts. The 1-830 axial vibration transmitters are similar to the 1-828 in many performance specifications. However, it is engineered to provide a propor-tional output relative to the target’s axial (thrust) position as sensed by the probe and extension system.

Differences in performance include a current output that is scaled at 4 to 20 mA, where 4 mA equals 25 mils gap and 20 mA equals 80 mils gap. The unit operational range is 50 mils (±25 mils from 50 mil offset) with an accuracy of ±5% at 25°C. It should be noted that the system accuracy is dependent upon the sensor providing specific impedance variations throughout the
calibrated range. Any change in the sensor’s characteristics from the standard may result in deviations from the calibrated output.

All transmitters include a problem failure detect system with LED indication and analog output correlation. If the probe is too close to the target the output will go below 2.5 mA. If the
probe is not connected or is too far from the target the output will go to 20.5 mA. Both the 1-828 and 1-830 series are approved for use in hazardous applications and include North American and European certifications.

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