4 Calibration Procedures64 Keysight 34970A/34972A Service GuideCalibration ProceduresThis chapter contains procedures for verification of the instrument’s performanceand adjustment (calibration). These procedures are required only if the internalDMM is installed. The chapter is divided into the following sections:– “Keysight Technologies Calibration Services” on page 66– “Calibration Interval” on page 66– “Time Required for Calibration” on page 67– “Automating Calibration Procedures” on page 67– “Recommended Test Equipment” on page 68– “Input Connections” on page 69– “Calibration Security” on page 71– “Calibration Message” on page 74– “Calibration Count” on page 74– “Calibration Procedure” on page 75– “Aborting a Calibration in Progress” on page 75– “Test Considerations” on page 76– “Performance Verification Tests” on page 77– “Internal DMM Verification Tests” on page 80– “Optional AC Performance Verification Tests” on page 87– “Internal DMM Adjustments” on page 88– “–10 VDC Adjustment Procedure (Optional)” on page 92– “Plug-in Module Test Considerations” on page 94– “Relay Verification” on page 95– “Thermocouple Reference Junction (Optional)” on page 119– “34907A Analog Output” on page 122