Tecfluid AMD For DP Series - Manual (Page 4)

5 MAINTENANCE
Electrical verification of the limit switch
If you have the NAMUR amplifier, power it on and check that the voltage at the terminals
+ and - is over 7.5 V when the vane is in the slot.
Connect a multimeter with the scale in DC mA, in series with the terminal +.
Verify that the current is less than 1 mA when the vane is in the slot, and more than 3 mA
when the vane is out of the slot.
If you don’t have the NAMUR amplifier, the current can be checked using the following
circuit diagram:
In order to make the electrical connection of the instrument, the limit switch has a screw
terminal strip.
For the electrical installation it is recommended to use multiple conductor cables with
individual cable sections in the order of 0.25 to 0.5 mm
2 in order to make it easier to
connect. Loose cables should not be used given that they can affect the seal of the cable
glands. It is better to maintain the mains cables separated from the cables with low level
signals.
Before starting the installation, check that the cable glands are the right size for the cables
to be used, this will guarantee the instrument will stay watertight. The supplied PG11
cable glands are for cables with outside diameters between 6 mm and 10 mm.
Peel the outside insulation to free the inner cables. It is recommended to tin the ends of
the wires to avoid loose ends. Next, feed the cables through the cable glands, and
connect to the corresponding screw terminals. Last, tighten up the cable glands so that
they maintain their degree of protection (IP). The numbering of the terminals is given on
the printed circuit board.
4
Limit switch needles Fixing nuts