Devices made in accordance with the requirements of IP67 (Waterproof) have tight test lead jacks. It is important that the insertion of the test leads is performed without gaps. The edges of test leads have special grooves for sealing against water.
Therefore the test leads should be inserted with a lot of effort (pushed forcefully into the jacks of the instrument) in order to achieve tight connection. Otherwise the test leads will not be securely connected to the jacks of the measuring instrument.
Tight connection of the test leads to the instrument is an essential condition for all Waterproof measurements in accordance with the terms of IP67. To verify the correct connection mode, set rotary switch to the continuity mode and press the MODE button.