Saelig Company, Inc. announces the availability of the Saker-MV ISOVP Probe, a voltage probe that allows high voltage isolated measurements via fiber optic cables. Optical fiber isolation provides high voltage safety and increased signal integrity due to absence of induced interference from external fields. This also allows for much higher common mode rejection (CMR) as compared to conventional differential probes. The probe head can be remotely put in standby, or even powered off, for increased user safety and battery power savings. The user therefore does not need to reach into potentially hazardous high voltage areas to turn off the equipment when measurements are not needed. Up to 15 m of fiber cable can be fitted between the probe head and receiver. The probe uses standard 1.5V AA batteries, with LEDs to indicate low battery conditions. 

The ISOVP probe has been designed with minimal input capacitance to facilitate high frequency measurements. Typical analog optical links are prone to minor power variations due to connector mismatches, temperature drifts, and offsets. The Saker-MV probe uses a proprietary algorithm to calibrate the link and eliminate those errors. This increases overall accuracy as compared to other optical equipment and saves setup time. 

The ISOVP probe can perform “hot” calibrations with no input disconnect, making it unnecessary to access the high voltage area during operation. This means saved time and increased user safety. Another useful feature puts the probe system in standby or turns off the probe head from the receiver so that the user does not need access to areas that can be at high voltage during tests. Most high-end oscilloscopes feature proprietary input connectors that force the user to choose the manufacturer’s supplied accessories of the scope, however the ISOVP probe can be used with any 50Ohm terminated oscilloscope. This gives developers freedom to use their digital scope of choice and contain overall investment costs. The probe head features a standard camera tripod mount thread. This makes it more convenient to place the probe inside tightly spaced cabinets or power modules to maintain proper clearance distances. 

Floating measurements have become an important part of modern power electronics and switching element design for IGBTs, MosFETs, thyristors, etc. Gate voltages need measuring, and modern topologies usually stack these semiconductors in order to handle higher voltages. Differential probes have been the staple in the measurement of floating voltages. However, they are not true isolated devices since their bandwidth is modest and common mode rejection is limited both by high frequency signals and sources with mismatched impedance. They are often noisy and not suited for also measuring low voltages. 

Features

  • Low input capacitance
  • “Hot” gain and zero auto-calibration
  • Low noise 
  • 3m, 7m and 15m cables available
  • Up to 175MHz BW, 200MHz@-4dB typical
  • Remote standby and power-off
  • Camera-type mount thread on probe head 
  • Runs on standard AA batteries

Applications include power electronics, multi-level power inverters (CHB, NPC, FC), EMC/ESD measurements, floating sensor outputs, differential measurements, partial discharge measurements, high voltage research, wind and EV power systems, etc.