Rigol DM3068, Руководство по обслуживанию

Страница: 36 / 70

RIGOL Chapter 2 Performance Test
Service Guide for DM3068
2-6
2. 3 Test Conditions
For best performance, we advise following items throughout all testing processes:
1. Always operate the instrument under a proper voltage.
2. Make sure the ambient temperature during the test is stable and within 18 °C
and 28 °C.
3. The relative humidity should be less than 80%.
4. Warm up the instrument for at least 90 minutes before testing.
5. Use a copper connector to reduce its thermoelectric potential effect.
6. Use a Teflon insulation shielding paired cable and as short as possible in order to
reduce the external interference effect. In the process of capacitance testing, a
coaxial cable should be used to minimize the external interference and noise.
7. Ground the shield of both twisted-pair and coaxial-cable, as well as the LO
terminal of calibrator (unless otherwise specified).
The DM3068 was designed for high precision, you must be more careful while testing
or calibrating in order to avoid errors. In an optimal situation, the accuracy of test
and calibration standard source must be four times at least than that of the test
instrument.
While performing the gain calibration for DC voltage, DC current and resistance, the
“0” output of the calibrator must be correct. In order to reduce the connection errors,
enough warm-ups must be done before each reconnection of cable or short-circuiter.
5 minutes is often needed for the warm-up.