Burkert Type 8025 - Handbuch (Seite 19)

17
Installationandwiring
7.4 Wiring
danger
risk of injury due to electrical voltage.
▶ Shut down the electrical power source of all the conductors and isolate it before carrying out work on the
system.
▶ Observe all applicable accident protection and safety regulations for electrical equipment.
Insert the supplied stopper gaskets into the unused cable glands of a wall-mounted version to ensure the
tightness of the device.
Only move the selectors when the power supply is off.
• Use a filtered and regulated 12-36 V DC power supply.
• Make sure the installation is equipotential. See chap. “7.4.1”.
• 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 device power supply by means of a 300 mA fuse and a switch.
• Protect the power supply of each transistor output by means of a 125 mA fuse.
• 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.
7.4.1 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 earthing
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 8025 UNIVERSAL