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Machine Guard MG4-REF11 A
SPM Instrument AB
• Box 504 • SE-645 25 Strängnäs • Sweden
Technical data are subject to change without notice.
Tel +46 152 225 00 • Fax +46 152 15075 • [email protected] • www.spminstrument.com
ISO 9001:2000 certified © SPM 2017-09. 71947 B
TRV-18/19
TRV-20/21
Insulation foot
TRX-18/19
Max. 50 m cable
Vibration transducers
The transducers SLD121/TRV-18/19 (linear frequency range up to 1000 Hz), SLD122/TRV-20/21
(linear frequency range up to 5000 Hz) and SLD144 (linear frequency range up to 10000 Hz) are
piezoelectric accelerometers of compression type. They have built-in pre-amplifiers and are power
supplied (24 Vdc) from the MG4. This allows the detection of a short or open circuit in the trans-
ducer line. The cable length between transducer and measuring unit is max. 50 m (165 ft.).
The nominal transducer output for SLD121/TRV-18/19 is 1.2 mV per m/s
2
. SLD122/TRV-20/21
has 4.0 mV per m/s
2
and SLD144 has 10 mV/m/s
2
. The actual transducer output is printed on the
transducer’s calibration card. This value is input as part of the measuring channel configuration.
The transducer is mounted against a smooth, flat surface on the machine. Transducers of type SLD
have thread size M8 or UNF1/4”. They have SMB connector for coaxial cable or 2 pin connector
for twisted pair cable.
TRV-18 and TRV-20 have thread size M8, while TRV-19 and TRV-21 have thread size UNF 1/4”-28.
Transducers of type TRV are delivered with three washers for adjusting the connector angle. Each
washer turns the transducer 90°. The coaxial cable (SPM 90005-L or 90267-L) with TNC connector
must be secured with a clamp close to the transducer. In moist environments, use sealing TNC cable
connectors (SPM 13008, 15291 or 15837) to prevent cable corrosion. As a rule, an insulation foot,
either TRX-18 for M8 or TRX-19 for UNF 1/4”-28, should be used to provide electric insulation.
The reason is that differences in earth potential between transducer and MG4 can cause measuring
faults. Note, however, that the installation foot limits the linear range of the transducer to ≈ 2000 Hz.
Transducers of type SLD has temperature range –40° to +125° C (–40° to +260°F). TRV-18/19/20/21
has temperature range –20 to +125 °C (4 to +260 °F). The coaxial cable SPM 90005-L is specified
–25 to +70 °C (–13 to +158 °F). The measuring cable SPM 90267-L is specified –55 to +150 °C
(–67 to +302 °F).
SLD121
SLD122
SLD144
Содержание Machine Guard MG4-REF11A
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