Keithley 2188 Low-Thermal Calibration Shorting Plug

The Keithley 2188 is shown in Figure 1. This low-resistance, low-thermal shorting plug is required to calibrate the Model 2182 Nanovoltmeter. As shown in Figure 2, all four terminal pins are shorted together. The shorting plug is made up of a LEMO connector whose pin connectors are shorted together using copper wire and SN/AG4 silver solder.

Input Terminal Cleaning

Before connecting the shorting plug to the LEMO input connector on the Model 2182, clean the copper contacts of the connectors using DeoxIT D100L deoxidizing solution as follows:

NOTE The following procedure uses DeoxIT to remove oxidation from the contacts of the shorting plug and the LEMO input connector. A bottle of DeoxIT is supplied with the Model 2182 Nanovoltmeter.

1. Turn off the Model 2182 and, at the rear panel, disconnect the line cord and any other cables or wires connected to the instrument.
2. Stand the Model 2182 on end such that the front panel is facing up.
3. Apply one drop of DeoxIT to each of the four contacts of the LEMO input connector on the Model 2182. You can use a clean wire (such as a resistor lead) to carry a drop of the solution from the bottle of DeoxIT to the connector.
4. Wipe off any excess DeoxIT using a clean cloth.
5. To clean the contacts of the shorting plug, connect and disconnect it to the Model 2182 several times to spread the DeoxIT around.