The 1865 Megohmmeter/IR Tester is a general purpose high voltage instrument for resistance measurements on insulating materials and components. It is designed for easy, accurate and direct readings of high resistance typically found in synthetic resins, porcelains, insulating oils, plastics and other similar materials. It is also used for measurements on capacitors, transformers, switches, cables and connectors. The 1865 provides a direct readout of resistance from 1000Ω to 1000TΩ with fully automatic ranging. The voltage applied to the unknown is programmable from 1V to 1000V. The 1865 includes a high resolution graphics display and keypad for ease of use. The test cycle is fully automatic with programmable charge, dwell, measure and discharge times. These times, along with other test conditions can be stored in instrument memory and recalled for later use. A pass/fail indicator provides the operator with a visual indication based on a preset resistance limit. The unit also contains automatic zeroing at the test leads as well as built-in self-test routines. Safety features include current limiting to less than 2mA and a front panel indication when voltage is applied to the test terminals, thus permitting connections to be made safely. The 1865 comes standard with I/O Port (handler) and RS232 interface. An IEEE-488 interface is optional for communication with other instrumentation and remote control operation. A 3 1/2" floppy drive option is also available for storing test conditions and results. There is a direct reading current measurement mode from 1mA to 1pA. The unit is available with front or rear panel input connections with guard and ground terminals to permit measurements of grounded or ungrounded devices.