Comtest, sole authorised South African distributor of Fluke Industrial and Electrical test tools, has announced the latest addition to Fluke’s ScopeMeter 120 range with advanced features for installing and troubleshooting fieldbuses and electrical machines.
The new ScopeMeter 125 performs a bus health test on industrial buses, for example, which can be a major headache for service, maintenance and installation (SMI) engineers. The test quickly determines whether the bus is working and if not, helps to identify the cause. The rugged ScopeMeter works with many industrial networks including AS-I bus, CAN-bus, Profibus, Foundation Fieldbus and Ethernet.
In addition, the instrument can test power input, sensor timing, motor windings, drive output timing and power measurements, thus eliminating the need for expensive and specialised test equipment.
The ScopeMeter 120 Series meters integrate oscilloscope, true-RMS digital multimeter and dual-input paperless recorder in one instrument. The ScopeMeters are 600 V CAT III safety certified for machinery, instrumentation, control and power systems. The new 125 has all the features of the successful 123 and 124 ScopeMeters and, in addition to the bus health test, it also carries out effective (Vpwm) voltage measurements of motor drive output, and has 0,01 Ω resolution on the 50 Ω range for testing motor windings. User-named data setups make for easy use.
Simple good/bad readout for fieldbus parameters
The bus health tests of the ScopeMeter 125 find defects like bad or missing terminators, bad cable splits, missing links, incorrect line loading, line interrupts, short circuit conditions and reflections. The instrument continuously acquires the bus signal and compares parameters to official specifications. It displays bus speed and measures signal quality with good or bad indications for parameters like rise- and fall-time, amplitude, bias level, pulse width and distortion. The instrument checks at the hardware (not protocol) level. An eye-pattern mode allows for a visual check of signal integrity.
Harmonic analysis and power consumption
Extended harmonics analysis of mains waveforms reaches up to the 33rd harmonic. That of course includes the important 3rd and 5th harmonics, which may be the cause of overheating in neutral wire or motor, as well as flat-topping of the mains voltage from non-linear loads like switch-mode power supplies. The wide frequency range covers railway (16,66 Hz) and airplane systems (400 Hz) applications.
Power measurements cover single-phase and balanced-3-phase, 3-wire systems (Watt, VA, VAR and Power Factor). Unlike PQ analysers, the instrument is not restricted to 50/60 Hz, and can measure power at the output of motor drives and frequency converters.
The Vpwm measurement capability shows the output voltage of motor drives exactly as the motor perceives it. For electrical and combustion engines, the 125 can indicate revolutions-per-minute (rpm), and can be set up for one or two rotations per pulse, or one rotation per two or four pulses. A 50 Ω resistance range brings excellent 0,01 Ω resolution for checking motor windings and other wiring.
Series automates measurements from industrial systems
This ScopeMeter 120 Series performs automated measurements on motor, switch and similar signals. The 123 has a 20 MHz bandwidth, while the 124 is a 40 MHz bandwidth instrument that performs more advanced measurements. The 125 is also a 40 MHz instrument but includes features for testing fieldbus and motor performance. All incorporate Fluke's unique Connect-and-View to recognise signal patterns, and automatically set up correct triggering.
The Fluke 125 includes a power adapter, test leads, 40 MHz probe, BP120MH battery (up to seven hours operation) and i400s current clamp. The Fluke 125/S adds FlukeView software, carrying case and OC4USB cable.
