ADS Environmental Services FlowShark Pulse QR 775004 A1 - Manual (Page 72)

Installation 6-27
Overvoltage Protection Precautions
To adequately protect the FlowShark Pulse transmitter, the power supply and mA-
output must have protection. ADS recommends EnerPro 220Tr, EnerPro 24Tr surge
arrestors (for 24 V DC) for the mains supply and the DataPro 2x1 24/24Tr for mA-
outputs.
The flow velocity sensor and the LUS air-ultrasonic sensor have internal protection
against overvoltage. Provide protection against higher voltages using the DataPro
2x1 24/24 Tr and DataPro 2x1 12/12 –0.3 Tr(N).
Using overvoltage protection elements reduces the maximum
allowable cable length.
DataPro 2x1 12/12 –0.3 Tr(N) overvoltage protection will consume
up to 300 mV. The line resistance is 0.3 Ohm/wire. This resistance
must be taken into account with the total allowable resistance
(refer to Sensor Connection on page 6-17).