Hach-Lange EVITA OXY Basic User Manual - Manual (Page 93)

English 93
Strip cable
Strip the cables (20 mm) and the earth wire (30 mm). De-insulate the litz
wires (6 mm).
Figure 9 Strip cable
Connection of the 100-240 VAC power supply
Single position transmitter OXY 4100/4150/3150
The transmitter is connected with the two-wire, shielded cable. Thus is
the connection to the mains power supply, to the HART
® communication
system and the transfer of a 4–20 mA current signal guaranteed.
Figure 10 EVITA ® OXY connected to a display
The extension cable must not be longer than 1000 m. Also use for the
extension only two-wire, shielded cable (at least 2 x 0.2 mm²) (24 AWG).
Note: Components such as motors, pumps and computers can cause
great potential differences between the protective ground conductor and
the medium to be measured. This can lead to fluctuating measurement
values. If this problem occurs, you should install a ground electrode in
the container in order to induce a potential equalization between the
medium and PE. If the flow rate in the container is high, a static potential
may occur locally. Place in this case the ground electrode near to the
transmitter.
Note: The observance of the IP protection class of housing and screw
connections can only then be guaranteed if the blind screw connection is
correspondingly tightened and the cable thickness is a corresponding
diameter.
For the connection to the general power supply (overvoltage class II)
a separate fuse or an emergency stop switch must be installed
(maximum 15 A). This equipment must satisfy the corresponding
requirements of IEC 947-1 and 947-3.
It must be located near the devices, be easily accessible for the user
and marked as a disconnecting device.
D A N G E R
Risk to life through electric shock. If no good protective ground with low
impedance is connected, this can lead both to dangerous electric shocks and also
to a poor protection against electromagnetic interferences.
6 m m
2 0 m m
3 0 m m
6 m m
N O T I C E
For the power supply of the EVITA ® OXY transmitter a separate power supply
must be used. If the OXY transmitter is connected directly to an existing 12–30 V
DC power supply, this must meet the following conditions:
- the power supply must be in accordance with NEC (National Electrical Code) a
power source of the class 2 (limit current)
- and a strengthened/double insulation between the power cables and the
power supply for the OXY transmitter