HT instruments FULLTEST3 - Manual (Page 44)

FULLTEST 3
EN - 43
To include standard mains over-voltage, the measured residual voltage is scaled to peak value of max.
possible mains over-voltage, i.e.:
a) Selected nominal voltage Un = 230 V
Up = 230 V Ч 1.1 Ч 1.41 = 358 V ....................... system voltage 230 V is recognized
Up = 400 V Ч 1.1 Ч 1.41 = 620 V ....................... system voltage 400 V is recognized
b) Selected nominal voltage Un = 240 V
Up = 240 V Ч 1.1 Ч 1.41 = 372 V ....................... system voltage 240 V is recognized
Up = 415 V Ч 1.1 Ч 1.41 = 644 V ....................... system voltage 415 V is recognized
If actual mains voltage differs from nominal system voltage more than 10%, the FULLTEST 3 scales
the result to peak value of actual input voltage.
Example 1 (Un = 230 V):
U IN = 173 V (the value differs more than 10% from 230 V), result is scaled to 173 V × 1.41 = 244 V
Example 2 (Un = 230 V):
U IN = 209 V (the value differs less than 10% from 230 V), result is scaled to 230 V Ч 1.1 Ч 1.41 = 358 V
5.8.2. EXPLANATION OF NONLINEAR MODE
In non-linear mode it is assumed there are also " non-linear " or unknown components involved in
discharge process (relays, gas lamps etc.) and therefore discharge characteristic is non-exponential or it
is unpredictable, see the diagram below.
t 1s / 5s
U
Some relay may be switched off
U (measured) RES
Coincidential switch off
at any mains voltage
Figure 31 : Discharge diagram in non-linear circumstances
In this case result can not be scaled to peak value, so it must be assured that switch off occurs at max.
input voltage i.e. at pick value (± 5%), otherwise measured result is not relevant. Measured value is
then registered and evaluated.