Lc Display And Operation Elements; Display; Operation Element; General Information About Rcd Tests - Unitest TELARIS Fi/RCD Manual De Instrucciones

LC Display and Operation Elements/ General Information about RCD Tests

4.0 LC Display and Operation Elements

4.1 Display

The explanations to the single symbols and indica-
tions are explained at the measurings.

4.2 Operation Element

1) LC-Display.
2) Key "S" to set the selective trip curren
3) Key "UL" to set contact voltage threshold.
4) Rotary switch for setting nominal trip currents .
5) Contact Electrode "PE"
6) Measurement "start" key.
7) Mains plug incl. spiral cable (fixed to instru-
ment).
8) Battery casing (instrument rear)
1
2
4
6
18
3
5
7
8

5.0 General Information about RCD Tests

The contact voltage UB and the trip time t required
by the RCD to disconnect the subsequent current
circuit from the mains represent important mea-
surement units for the asessment
of an RCD.
For this reason, IEC 60364 prescribes that
a) the maximum allowable value for the contact
voltage (25V/50V) may not be exceeded within
any system during tripping at nominal residual
current.
b) the RCD must trip within a certain time limit of
300ms.
The task of an residual current device (RCD) con-
sists in switching off a system within a defined time
period after an error prior the contact voltage reach-
es the admissible limit value of 25V / 50V.
The system testing should be started by carrying out
a visual inspection, in particular of the protective
earth connection.
1. Within the IT system, the protective earth con-
ductor doesnot have to be connected with the
PEN but with the protective earth connection.
2. The protective gearth conductor must be con-
nected to the PEN prior to the RCD within the TN
system.
3. An insulation measurement must be performed.
In particular it must be proofed, that there is no
connection between N and PE following the RCD.
4. Proof regarding the low impedance connection of
equipotential bonding conductors must be avail-
able.