Grundfos ALR 20/A Ex Instrucciones De Instalación Y Funcionamiento página 7

3.2 Electrical connection
CAUTION
Electric shock
Minor or moderate personal injury
- Switch off the power supply before you
start any work on the product.
- Make sure that the power supply cannot
be accidentally switched on.
• A fuse has to be integrated into the power supply
circuit. Use a 250 V AC, 0.032 A fine-wire fuse
(slow-acting) in accordance with IEC 60127.
• The whole cabinet, which the ALR 20/A Ex and
its fuse is part of, must be equipped with a circuit
breaker according to IEC 60947-2 or an
equipment switch according to IEC 60947-3.
Carry out the electrical connections according to
local regulations.
For all electrical connections see fig. 1.
L N
Fig. 1 Electrical connections
Terminal
2 (A1)
10 (A2)
1-3; 1-4
5-7 (clamp light blue)
Function
Power supply (L - phase)
Power supply (N - neutral)
Relay outputs
Sensor
3.2.1 Connection of main power supply
The power supply has to be connected with terminal
2 and 10 according to the label on the cover. Use
adequate wires for main power supply.
3.2.2 Connection of relay contacts
A change-over switch acts as output signal.
According to the marking the maximum switching
current is 5 A.
Relay outputs
Operation Relay function
Relay contact 1-4 closed
No leakage
detected
Relay contact 1-3 open
Relay contact 1-4 open
Leakage
detected
Relay contact 1-3 closed
3.2.3 Leakage sensor connections
If the feed cable is being extended, follow
the ATEX-directives, standards EN 60079-
11 and EN 60079-14 to maintain the
intrinsic safe circuit.
For intrinsically safe and nonintrinsically
safe circuits the clamp connections must
be separated and marked unmistakably.
The operator has to make sure that all
installation works are done in conformity
with the relevant standards.
The sensor cable leads 21 and 22 have to be
connected to the light blue terminal 5 and 7. For
additional extension a screened cable should be
used. The maximum length of the cable from
ALR 20/A Ex to leakage sensor is 50 m.
As an alternative to forward the signal over longer
distances (> 50 m), use the potential-free outputs
(terminal 1 and 4).
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