Applied Precision WS 2120, Руководство пользователя

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Working Standard
User’s Guide
www.appliedp.com
WS-UGFW619-EN
103
6.5 Measurement Time
Measurement Time (time needed for new sample) is defined by Integration Time, which is stated in
Test Settings of device.
If time between marks / impulses from the meter under test is longer than Integration Time then
Measurement Time is equal to time between capturing marks from the meter.
6.6 Measurement Error
Measurement Error Limits (tolerances of precision) in basic load points and temperature 23 °C are
defined in technical specification. Measurement Error Limit for power measurement in other load points
and temperatures is:
( )
TEMP PHASE AMPL W S
LIMIT LIMIT LIMIT LIMIT
+ + 
2 2
LIMIT
WS
............... overall error [in %]
LIMIT
AMPL
............ amplitude error [in %] (defined in technical specification)
LIMIT
PHASE
........... phase error [in %]
LIMIT
TEMP
............ temperature error [in %]
Calculation of phase error for active power:
PHASEDEG PHASE
LIMIT K tg LIMIT
   =
) ( 100

Calculation of phase error for reactive power:
PHASEDEG PHASE
LIMIT K g LIMIT
   =
) ( cot 100

Calculation of temperature error:
TC T T LIMIT
SPEC TEMP
 − =
K ......................... conversion constant (to radians):
0175 . 0
180
 =

K
φ
......................... phase angle between voltage and current [°]
LIMIT
PHASEDEG
...... phase error [in %] (defined in technical specification)
T .......................... temperature at measurement
T
SPEC
.................... temperature defined in technical specification: T
SPEC
=23
˚C
TC ....................... temperature coefficient of the device:
TC
= 0.005 %/˚C .......... for WS 2x20B and WS 2x20A
TC
= 0.010 %/˚C .......... for WS 2x20C