
The IRS-1 tests for reference electrode contact resistance. The IRS-1 switch is a portable push button device which momentarily changes the input impedance of a digital multimeter to 1MΩ from its normal value, typically 10MΩ. This feature permits the Corrosion Technician to detect high resistance in the external circuit, such as faulty test lead connections or high resistance contact between a reference electrode and the electrolyte.