• In most of inspections of small fan before delivery, operators perform sensory tests. Inspections of rattling or abnormal sound etc. at rated speed depend on senses of operators. Recent years, shifting production to overseas requires quantitative determination for stable products in quality. In this example, the VC-3100 and accelerometers detect rattling or abnormal sound and make level determination by mounting sensors on a fan at radial and thrust directions (magnetic attachable/removal). There are several methods to mount sensors on a fan such as pressing sensors on a fan by jig or mounting sensors on a preliminarily fixed jig. The latter method enables detection of vibration which is transmitted to a jig. When it is difficult to make a structure for pressing a sensor on a measurement object.
• The VC-3100 can be setup three frequency bands and make OK/NG determination based on the rms, peak, or crest factor value on each band. Also it has effective functions such as comparator delay time setup function and auto operation function. The comparator delay time setup function removes unwanted signal at the time of starting measurement and the automatic operation function can control the timing of determination by inputting a control signal from external device such as PLC*. Although the VC-3100 can be operated by 24VDC (22 to 26VDC) as standard, you have an alternative to use it at 100 VAC by connecting an optional AC/DC convertor VC-0352.
• Connecting the VC-3100 to a PC via RS-232C interface enables storing measured data and so on.
• By connecting a pair of commercially sold headphones to the VC-3100, it is possible to make hearing check of the vibrating sound. Moreover, it can be used instead of conventional stethoscopic probe. Output signals are provided for each band, enabling an observation for vibration phenomenon on each frequency band separately

* PLC: Programmable Logic Controller