TESTBOY TV 450
Testing RCD
38
RCD type
Contact voltage Uc
proportional to
Rated I
Δ
N
AC G
1.05
×
I
Δ
N
AC
S
2
×
1.05
×
I
Δ
N
any
A G
1.4
×
1.05
×
I
Δ
N
A
S
2
×
1.4
×
1.05
×
I
Δ
N
≥
30 mA
A G
2
×
1.05
×
I
Δ
N
A
S
2
×
2
×
1.05
×
I
Δ
N
< 30 mA
Both models
B G
2
×
1.05
×
I
Δ
N
B
S
2
×
2
×
1.05
×
I
Δ
N
any Model
TESTBOY
TV 450 (Type B)
only
Table 5.1: Relationship between Uc and I
Δ
N
Loop resistance is indicative and calculated from Uc result (without additional
proportional factors) according to:
N
C
L
I
U
R
Δ
=
.
UK version
Figure 5.18: Example of contact voltage measurement results
Displayed results:
Uc........Contact voltage.
Rl.........Fault loop resistance.
5.4.2 Trip-out time (RCDt)
Trip-out time measurement verifies the sensitivity of the RCD at different residual
currents.
Trip-out time measurement procedure
* model TESTBOY TV 450 (TYPE B)
Select the
RCD
function using the function selector switch.
Set sub-function
RCDt.
Set test
parameters
(if necessary).
Connect
test cable to the instrument.
Connect
test leads to the item to be tested (see
figure 5.17
).
Press the
TEST
key to perform the measurement.
Store
the result by pressing the MEM key (optional)*.
