KEPCO MST 100-2MHT, Руководство оператора

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3-8
MST-MHT SERIES 071320
3.9 CALIBRATION
Calibration of the MST-MHT Power Module is recommended for any of the following conditions.
• Operating environment (temperature, humidity, etc.,) higher than 30°C.
• Periodic maintenance determined by user.
• Inaccurate measurements are suspected.
Perform the procedures outlined below in sequence (see Figure 2-2 for the location of calibra-
tion controls). Calibration adjustments are recommended only when the test point value
exceeds the indicated tolerance on the measured value. Note that the measured value toler-
ance is generally an order of magnitude looser than the adjustment tolerance. This avoids
unnecessary recalibration, while providing a precision adjustment if calibration is required.
NOTE: E
MAX
is the maximum output voltage of the unit listed in Table 1-1; I
MAX
is the maxi-
mum output current of the unit as listed in Table 1-1 for 45 ° C.
3.9.1 EQUIPMENT REQUIRED
Calibration of MST-MHT Series Power Modules requires the following equipment:
• Host computer
• RA 55H or CA 400H Rack Adapter, or Input Power/Communication Cable (see Table 1-
3)
• Controller Module (Kepco MST 488-27HT)
• Digital Voltmeter (DVM): 6½ digit display, 10

V resolution
• Precision Current Shunt: R
SHUNT
< 0.02 (EMAX / IMAX)

where: E
MAX
= rated Power Module output voltage (e.g., 36V for MST 36-5MHT)
I
MAX
= rated Power Module output current (e.g., 5A for MST 36-5MHT)
NOTE: To avoid errors due to temperature drift of the shunt, a power rating of
greater than 10 times actual dissipation is recommended. The above calcu-
lation results in a maximum shunt power dissipation of less than 4W, a 100W
shunt is adequate for all models)
• Miscellaneous programming interface cables, load cables, etc.
Install the MST-MHT Series power module under test (UUT) in the calibration test set-up shown
in Figure 3-1