Model 2500 Service Manual Calibration 2-3
 
Calibration considerations
 
When performing the calibration procedures:
• Make sure the test equipment is properly warmed up and connected to the Model 
2500 input or output terminals as required.
• Allow signals to settle before calibrating each point.
• Do not connect test equipment to the Model 2500 through a scanner or other 
switching equipment.
• If an error occurs during calibration, the Model 2500 will generate an appropriate 
error message. See Appendix B for more information.
 
WARNING
 
The maximum common-mode voltage (voltage between LO and 
chassis ground) is 200V DC. Exceeding this value may cause a shock 
hazard.
 
CAUTION
 
Maximum signal on OUTPUT connectors is 100V @ 20mA DC. 
Maximum signal on INPUT connectors is 20mA. Exceeding these 
values may result in damage to the instrument.
 
Calibration cycle
 
Perform calibration at least once a year to ensure the unit meets or exceeds its 
specifications.
 
Recommended calibration equipment
 
Table 2-1 lists the recommended equipment for the calibration procedures. You can use 
alternate equipment as long as that equipment has specifications at least as good as those 
listed in the table. For optimum calibration accuracy, test equipment specifications should 
be at least four times better than corresponding Model 2500 specifications.