The SM-400 instrument is designed for measuring the magnetic susceptibility in holes with diameter of 40 mm and up tu 530 mm deep. The instrument´s sensor is located in a protective tube and during measurement, it moves up and down. The measured values are recordered and at the end of the measurement, they are transferred to a graph and saved in the computer memory. The sophisticated method for processing the signal significantly suppresses the effect of external electro-magnetic interference. The SM-400 is controlled by computer and does not have any control components. It us delivered with a transport box together with an accumulator, charger and cables.
The SM-400 susceptibility meter required a computer with the MS WINDOWS operating system for operation. The computer serves for data processing, data display and archiving and also for controlling the instrument including switching on and off. Switching off always takes place upon disconnecting the communication cable. There are no control componnets on the SM-400. Communication with the computer is via USB port. The SM-400 is supplied by a 12 V accumulator.
The SM-400 instrument is in the shape of a tube 40 mm in diameter with a length of 820 mm. A mobile carriage with a sensor moves inside the tube. The box with the electronics and a motor is attached to the tube at the upper end of the tube. The mobile carriage is connected to the box by two flexible wires. The total length of the instrument with the box is 890 mm.
There is a freely mobile sleeve on the tube connected by a cable to the box with electronics. During measurements, the sleeve automatically sets on the surface of the soil. Its position in regard to the tube during measurement is automatically determined and this data is used for assigning the depth to the measured data. On the lower side of the box there are three connectors. The middle one serves for communication with the computer. One of the two outer connectors is for connecting the sleeve; the other conects the instrument to the accumulator. The pins of both outer connectors are identically connected and therefore the appropriate cables may be interchanged.