Technical Instruction
Ex-Separator Module iXT0
Installation and connection
page 34
Ex-Separator Module iXT0 - rev. 02 / 28.08.2017
14 Overvoltage protection
For effective protection of the Ex-Separator Module iXT0 it is necessary to protect
power supply as well as mA-inputs and mA-outputs
using overvoltage protection
devices
. NIVUS recommend:
−
2-wire connection:
DataPro 2x1 24/24
−
RS485-Sensors (POA, CS2, OCL and OFR):
DataPro 2x1 12/12
SonicPro 3x1 24/24
The flow velocity sensors, the OCL air-ultrasonic sensors and the radar sensor are
internally protected against overvoltage within the usual EMC limits. Should you
expect higher risk potentials protect the sensors by using the following combina-
tion:
−
DataPro 2x1 12/12 in connection with SonicPro 3x1 24/24
Note
Consider the connected loads of the overvoltage protection devic-
es when using the sensors in Ex areas.
Please also ensure the capacity and inductance of the NIVUS
sensor cables (POA, CS2, OCL, OFR and EBM).
The maximum permissible NIVUS cable lengths in Ex areas are:
−
single-side overvoltage protection: 135 m (443 ft.)
−
double-side overvoltage protection: 120 m (394 ft.).
Note
Observe the non-reversed connection (p-side to transmitter) as
well as a correct, straight wiring supply.
Ground (earth) must lead to the unprotected side.
−
Wrong connection suspends the function of the overvoltage
protection!
