
T-NC/30-S NO CONTACT TRANSDUCER
FUNCTION
Transducer T-NC/30/S is used for performing the following measurements:
DIFFERENTIAL EXPANSION (ex.Turbine), i.e. relative movement between the rotor and the
machine casing; the measurement is made by mounting the sensor integral with the
machinery casing in the spot corresponding to the thrust block of known characteristics
prepared on the rotor. The picked up signal should be sent to the CEMB T2 unit for
processing.
AXIAL POSITION, (ex. Turbine Shaft Position with respect to the Thrust Bearing), the
measurement is made by mounting the sensor of each transducer on the machinery casing,
axially facing a block either mounted or obtained on the rotor close to the thrust
bearing, in order to measure the wear on the bearing. The signals picked up should be
sent of the CEMB T3 units for processing.
ECCENTRICITY, (ex.Turbine Shaft), the measurement is made by mounting the sensor of the
transducer on the machinery casing, radially facing a ring mounted or obtained on the
rotor, in order to measure the eccentricity of the rotor at low speed; the signal
picked up should be sent of the CEMB T4 unit for processing.
COMPOSITION
The transducer consists of a field-mounted sensor T-NC/30 and converter box T-NC/S
outside the machinery.
CEMB S.p.a.
Costruzioni Elettro Meccaniche ing. Buzzi & C. S.p.a.
Sede legale: Via Risorgimento, 9
23826 MANDELLO DEL LARIO - (Lecco) ITALY
Cap. Società ? 1.500.000 i.v.
Reg. Impr. Lecco 00221870132
C.C.I.A.A. Lecco REA 75997
Meccanografico LC 000078
C.F. 00221870132 -P.IVA IT 00221870132
Telefono +39 – 0341.706.111
Industry Div. Fax +39 – 0341.735.678
Garage Div. Fax +39 – 0341.700.725
www.cemb.com
Vibration Analysis Div. Fax +39 – 0341.706.299
Cap. Società ? 1.500.000 i.v.
Reg. Impr. Lecco 00221870132
C.C.I.A.A. Lecco REA 75997
Meccanografico LC 000078
C.F. 00221870132 -P.IVA IT 00221870132
Telefono +39 – 0341.706.111
Industry Div. Fax +39 – 0341.735.678
Garage Div. Fax +39 – 0341.700.725
www.cemb.com
e-mail: stm@cemb.com
Vibration Analysis Div. Fax +39 – 0341.706.299

2
PRINCIPLE OF OPERATION
The T-NC system generates a radio frequency field which is radiated by the sensor
surface.
When the reference surface facing the sensor is invested by such RF field, an eddy
current is generated on it. The energy required to generate such eddy current (which is
proportional to the distance between the reference surface and the sensor surface)
reduces, in proportion, the energy present in sensor. Such difference is then detected
by the converter.
The converter amplifies and processes this signal thus supplying a d.c. output voltage
proportional to the distance under consideration.
TECHNICAL CHARACTERISTICS
Composition : sensor, converter
Type of measurement : differential
Range of measurement : ± 6,5 mm
Range of application : Temperature (Sensor) = -20°C to +175°C
Temperature (Converter) = -10°C to +70°C
Humidity (Sensor) = max 100%
Humidity (Converter) = max95% with condens
Ambient (Sensor) = IP67 EN 60529/10.91
Ambient (Converter) = IP65 EN 60529/10.91
Sensitivity : 0.77 V/mm
Power supply : + 15÷24 Vdc; GND.
Connection : Connector MIL C-5015, series 3102/16, standard kit
Convert. casing material : Die-cast aluminium
Sensor casing material : Stainless steel
Weight of the converter : ~ 0.7 Kg
Weight of the sensor : ~ 0.5 Kg
Maintenance : None
Drawings enclosed : 19457 = Overall dimensions, mounting, connections.