Testboy TV 455VDE-tester Testboy TV 455 User Manual

Product codes
Testboy TV 455
Page of 76
TESTBOY TV 450 
Warnings and notes 
 
Continuity functions 
 
‰
 
If voltages of higher than 10 V (AC or DC) is detected between test terminals, the 
continuity resistance test will not be performed. 
‰
 
Before performing a continuity measurement, where necessary, compensate test 
lead resistance. 
 
RCD functions 
 
‰
 
Parameters set in one function are also kept for other RCD functions! 
‰
 
The measurement of contact voltage does not normally trip an RCD. However, 
the trip limit of the RCD may be exceeded as a result of leakage current flowing 
to the PE protective conductor or a capacitive connection between L and PE 
conductors. 
‰
 
The RCD trip-lock sub-function (function selector switch in LOOP position) takes 
longer to complete but offers much better accuracy of fault loop resistance (in 
comparison to the R
L
 sub-result in Contact voltage function). 
‰
 
RCD trip-out time and RCD trip-out current measurements will only be performed 
if the contact voltage in the pre-test at nominal differential current is lower than 
the set contact voltage limit! 
‰
 
The autotest sequence (RCD AUTO function) stops when trip-out time is out of 
allowable time period. 
 
Z-LOOP 
 
‰
 
The low limit prospective short-circuit current value depends on fuse type, fuse 
current rating, fuse trip-out time and impedance scaling factor. 
‰
 
The specified accuracy of tested parameters is valid only if the mains voltage is 
stable during the measurement. 
‰
 
Fault loop impedance measurements will trip an RCD. 
‰
 
The measurement of fault loop impedance using trip-lock function does not 
normally trip an RCD. However, the trip limit may be exceeded as a result of 
leakage current flowing to the PE protective conductor or a capacitive connection 
between L and PE conductors. 
 
Z-LINE 
 
‰
 
In case of measurement of Z
Line-Line
 with the instrument test leads PE and N 
connected together the instrument will display a warning of dangerous PE 
voltage. The measurement will be performed anyway. 
‰
 
Specified accuracy of tested parameters is valid only if mains voltage is stable 
during the measurement. 
‰
 
L and N test terminals are reversed automatically according to detected terminal 
voltage (except in UK version).