The unit meets the requirements of IS:11196, IS:2720 (Part V). This penetrometer is similar to HS10.20 Liquid Limit Cone Penetrometer except that the time of penetration of the cone is automatically controlled using a timing head and an Automatic Electronic Timer. The timer supplies 220 V smoothed D.C. output to the timing head precisely for 5 seconds to allow the cone to freely penetrate the soil in the trough. At the end of 5 seconds, the timer automatically de-energizes the releasing electromagnet and then relocks the cone. The reading is taken from the scale. This eliminates individual errors and gives consistance results. Suitable for operation on 220V, 50 Hz, single phase supply.