Tecfluid LTL-APR - Manual (Page 3)

3
In the female connector
Borne 1: Reed common
Borne 2: NO
Borne 3: NC
Borne Tierra: No connection
Terminal 2 is the normally open contact when the float is below the level switch.
For the electrical installation it is recommended to use multiple conductor cables to guarantee the
instrument will stay water tight.
The connector admits cable diameters from of 4.5 to 7 mm.
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 closes over the cable and that the
connector with the rubber seal is well screwed down to maintain the IP65 rating.
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 electro-valve coils, surge arresters should be
installed to protect the reed contacts.
With a DC supply, a diode should be connected as shown on the next figure:
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 Vrms working and will have a breakdown voltage of 39 V
at 1 mA.
CONNECTION