Tecfluid Series LT Instruction Manual page 26

Make sure that the contact rating is not exceeded. If high loads are to be switched, use an
auxiliary relay.
When using inductive loads, such as relays or solenoid valve coils, surge arresters should be
installed to protect the reed contacts.
With a DC supply, a diode should be connected as shown.
For an AC supply, a RC circuit can be used as shown, although a varistor (VDR) is better
and is easier to select the right value. The VDR should have a breakdown voltage greater
than 1.5 times the rms voltage. The standard varistor ratings specify the rms working voltage
for the varistor, for example a S05K25 varistor will be for 25 V working and will have a
rms
breakdown voltage of 39 V at 1 mA.
The electrical installation should provide a fuse or circuit breaker to protect the reed switch
from overloads.
When installing the connector, make sure that the cable gland (A) closes over the cable and that
the connector (B) with the rubber seal (C) is well screwed down to maintain the IP65 rating.
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