Thunder Scientific 2500 series, Руководство по эксплуатации и обслуживанию

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4-1
Section 4
CALIBRATION AND MAINTENANCE
4.1 GENERAL
The Series 2500 humidity generation system requires little periodic maintenance. Following
the proper operating procedures as given in this manual will help assure trouble-free
operation of this system.
4.2 CALIBRATION
Proper calibration of the temperature and pressure transducers is critical to the accuracy of
the generated humidity. Each time a transducer is calibrated its current calibration
coefficients and calibration data are stored to non-volatile memory. Although not critical to
system generation accuracy, the flowmeter coefficients and data are also retained in non-
volatile memory.
Calibration of the system requires the following support equipment:
1) Temperature:
A. Temperature bath with a liquid medium (recommend Fluorinert, a 3M product), a
range of 0-70 °C, and stability of ±0.01 °C or better. Less stable baths may require
the use of a thermal block.
B. Standard or reference thermometer (PRT or Thermistor) for the range of 0-70 °C with
a resolution of 0.01 °C or better. Thermometer accuracy should be ±0.05 °C or better.
2) Low Pressure (0-50 PSIA):
A. Static gas pressure source for the pressure range of ambient to 50 PSIA with a
stability of ±0.0025 PSIA or better.
B. Standard or reference pressure gauge for the range ambient to 50 PSIA with a
resolution of ±0.0025 PSIA. Gauge accuracy should be ±0.025 PSIA or better.
3) High Pressure (50-150 PSIA):
A. Static gas pressure source for the pressure range of 50 to 150 PSIA with a stability of
±0.01 PSIA or better.
B. Standard or reference pressure gauge for the range of 50 to 150 PSIA with a
resolution of ±0.01 PSIA or better. Gauge accuracy should be ±0.10 PSIA or better.
4) Flow:
A. Standard or reference flowmeter for the range of 0 to 20 L/min with a resolution of
0.1 L/min or better. Flowmeter accuracy should be ±0.5 L/min or better.