User guide

22
Installation and commissioning
• Use a high quality electrical power supply (filtered and regulated).
• Make sure the installation is equipotential. See chap. “7.3.1”.
• Use shielded cables with a temperature limit of 80 °C minimum.
• Do not install the cables near high voltage or high frequency cables; If this cannot be avoided, observe a
min. distance of 30 cm.
• Protect the power supply by means of a 300 mA fuse and a switch.
• Protect the relays by means of a max. 3 A fuse and a circuit breaker (depending on the process).
• Do not apply both a dangerous voltage and a safety extra-low voltage to the relays.
If two cables are used in the same cable gland, first insert the supplied multi-way seal.
To wire the device:
→ Loosen the screw from the lid.
→ Flip the lid.
→ Loosen the 4 screws from the cover of the housing.
→ Remove the cover.
→ Loosen the nuts of the cable glands.
→ Insert the cable through the nut then through the cable gland.
→ Make sure the earth cable coming from the housing and, on a version with stainless steel sensor, the cable
coming from the flow sensor, are connected as shown in Fig. 19, chap. 7.3.3.
→ Wire acc. to chap. 7.3.1 to 7.3.7.
7.3.1. Equipotentiality of the installation
To ensure the equipotentiality of the installation (power supply - device - fluid):
→ Connect together the various earth spots in the installation to eliminate the potential differences that may
occur between different earthes.
→ Observe faultless earthing of the shield of the power supply cable, at both ends.
→ Connect the negative power supply terminal to the earth to suppress the effects of common mode currents. If
this connection cannot be made directly, a 100 nF/50 V capacitor can be fitted between the negative power
supply terminal and the earth.
→ Special attention has to be paid if the device is installed on plastic pipes because there is no direct earthing
possible. Proper earthing is performed by earthing together the metallic instruments such as pumps or valves,
that are as close as possible to the device. If no such instrument is near the device, insert metallic earth rings
inside the plastic pipes upstream and downstream the device and connect these parts to the same earth. The
earth rings must be in contact with the fluid.
English
Type 8045