EN
14392029.02 08/2020 EN/DE
Operating instructions magnetostrictive level transmitter, models FLM-xAI, BLM-TAI (Ex)
19
5.2 Electrical connection
5.2.1 Connection diagram (Ex)
Prior to starting operation, please check all instruments for proper connection and
installation. Check the electrical supply, also of the connected instruments.
Voltage source U
max
= DC 30 V
Minimum supply voltage U
min
= 8 V
Overall resistance (incl. wiring resistance and load) ΣR = (U - U
min
) / 0.0215 A
In hazardous areas, the intrinsically safe version of the level transmitter may only be
connected to buffer amplifiers that are certified by a notified body and whose electrical
output data meet the following criteria:
U
0
≤ 30 V
I
0
≤ 100 mA / 200 mA
1)
P
0
≤ 1 W
▶
For further data, see the EC-type examination certificate at www.wika.com.
1) The permissible input current li depends on the ambient temperature T
a
.
Make sure that the permissible external capacitance C
0
and inductance L
0
of the buffer
amplifier are not exceeded if the level transmitter is used in a hazardous environment (see
chapter 6 “Safety-related characteristic values”).
The connection cable to the buffer amplifier must be marked in case of applications in a
hazardous environment - preferably as a blue cable for intrinsically safe circuits.
▶
Connection of the cable, see chapter 5.2.3 “Wiring with cable gland” and 5.2.4 “Wiring
with M12 connector”)
According to the dielectric strength requirements of EN 60079-11, section 6.3.13, there is
compliance with the insulation test between the intrinsically safe circuit and the chassis of
the level transmitter with a voltage of AC 500 V.
Wiring resistance
Supply voltage
Buffer amplifier (example)
5. Commissioning, operation
