June 19, 2014 (Nagano, Japan). Hioki E.E. Corp. has announced the launch of the CT6841 and the CT6843 AC/DC current probes (rated at 20 A and 200 A, respectively) for high precision testing applications, particularly in the electric-vehicle and hybrid-vehicle markets but also in solar power systems.
During development of electric and hybrid vehicles, the need to evaluate motor efficiency requires engineers to measure current flowing in wiring inside the engine compartment at a high level of precision. However, since wiring cannot be removed easily when measuring current in actual vehicles, pass-through current sensors cannot easily be used. Further complicating the task are high temperatures and a lack of space in the compartment, which houses both the engine and a complex network of wiring. These conditions demand compact, high-precision current sensors that can make measurements in a broad range of temperatures.
Principal applications for Hioki's newly launched CT6841 and CT6843 AC/DC current probes include evaluation of electric vehicle and hybrid vehicle motor efficiency (measuring current inside an engine compartment) and evaluation of the efficiency of inverters and power conditioners used in solar power systems.
The CT6841 and CT6843 can measure current across a broad frequency band over an operating temperature range of -40°C to 85°C, allowing their use in a broader range of temperatures than legacy models with a 0°C to 40°C range. This capability allows the instruments to be used to measure current inside hot engine compartments. Additionally, the new sensors are less susceptible to the effects of noise from nearby wiring than legacy models, allowing more accurate measurement.
Accuracy for the CT6841 and CT6843 is 0.3% of reading, vs. 0.5% of reading for legacy models. The measurement frequency bands for the CT6841 and CT6843 are DC to 1 MHz and DC to 500 kHz, respectively (vs. 100 kHz for legacy models).