Measuring Contact Voltage And Trip Test With Nominal Residual Current - Gossen MetraWatt ProFiTEST C-GB int. Operating Instructions Manual

If contact voltage U measured with
IN
projected to I by means of calculation is greater than 50 V (> 25 V), the
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U lamp lights up red.
L
If contact voltage U exceeds 50 V during testing, safety shutdown
IN
ensues.
Contact voltages of up to 99.9 V are displayed. Overflow is indicated for
larger values.
Limit Values for Permissible Continuous Contact Voltage
The limit for permissible continuous contact voltage is U
alternating voltage (international agreement).
Lower voltages are required in special applications (e.g. medical
applications U = 25 V).
L
6.2

Measuring Contact Voltage and Trip Test with Nominal Residual Current

After contact voltage has been measured, testing can be performed to
ascertain whether or not the RCCB is tripped within 400 ms, or 1000 ms,
at nominal residual current.
START
➭
Press the start START key in order to measure U
hold it depressed even after the measurement value has been
displayed. The trip test is started automatically after contact voltage
U has been measured.
IN
GMC-I Messtechnik GmbH
1
/ nominal residual current and
3
= 50 V for
L
, and continue to
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If the RCCB is tripped at nominal residual current, the NETZ/MAINS lamp
blinks red (mains voltage has been interrupted), and contact voltage U
and time to trip t appear at the display.
T
If the RCCB is not tripped at nominal residual current, the RCD/FI lamp
lights up red.
The trip test is only required at one measuring point for each RCCB.
!
Attention!
If contact voltage is too great, or if the RCCB is not tripped, the
system must be repaired (e.g. earthing resistance is too high,
defective RCCB etc.)!
The trip test must be performed at one of the three phases (L1, L2 and L3) in order
to assure flawless functioning of the RCD.
Note
Earthing resistance is automatically measured during the trip test.
However, the accuracy of the measured value depends to a great
extent upon the utilized measuring current. For example, the mea-
sured value is relatively inaccurate with measuring currents of
10 mA and 30 mA, because measurement resolution is reduced
due to minimal current. Better results can be obtained with the R
function (see chapter 8, page 29).
Note
Measurement Value Processing with PC Software (e.g. PS3)
Only one R measurement value is entered to some of the report
E
forms. In order to assure that the PC software enters the desired
value, enter the ! symbol as the first character in the comment line
after the value has been saved to memory (see chapter 4.5),
for example: !Foundation earth.
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E
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