Tettex MIDAS 2881, Руководство по эксплуатации

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Theory 17
* Maximum current trough “C
N INTERNAL
” is limited by 15kV / 100pF

470µA @ 50Hz
** The max. output power can also limit the maximum test voltage
*** Test current higher than 15A can’t be measured with this test system. External current dividers
(current comparators) would affect functionality and/or accuracy of the midas288X. For range
extension please contact TETTEX customer support.
Example:
U
Test
=10kV, C
X
=80nF (tan

< 0.01), f=50Hz, internal AC source used, built-in C
N
used
 I
X
= 251mA

within I
X
range – OK

> 150mA - Only intermittent testing allowed due to max. supply
output current limit
 P
supply
= 2513VA

within P range – OK
 I
CN
= 314 uA

within I
CN
range – OK
4.10 Parallel & Series Equivalent Circuits
The MIDAS measures and displays both - the parallel and/or series equivalent circuit values.
The following formulas describe the calculation of the value conversion parallel – series :
Figure 4 - Parallel equivalent circuit C
p
-R
p
Rp
Cp

 
1
 
tan * *
* measured values
Figure 5 - Series equivalent circuit C
s
-R
s
Cs Cp
  
* ( tan *) 1 2

Rs Rp
 

tan *
tan *
2
2 1


* measured values