Monitor 4-20mA current loop sensors
Analog signals, where information about the process is transmitted via varying amounts of voltage or current, are the predominant type of input in industries requiring process control today. Of all possible analog signals that can be used to transmit process information, the 4-20 mA loop is, by far, the dominant standard in the industry.
Applications
- Connecting industrial sensors to Vutlan monitoring systems for monitoring and control
- Measuring fuel level or other liquid in a tank
- Measuring the concentration of CO2 or other gases
- Connecting pressure transducers for the measurement of gases or liquids.
- Monitoring pH change for analysis of water or soil quality
- Monitoring and controlling other industrial sensors or devices
Components of a 4-20 mA Loop
a) 4-20mA current loop sensor
VT420 can convert signals from any 4-20mA current loop sensor. Depending on the source of current for the loop, devices may be classified as active (supplying or “sourcing” power) or passive (relying on or “sinking” loop power).
b) External power supply
If the sensor is passive, it requires an external current source. To help You choose the power supply voltage and amperage please read VT420 Technical Documentation.
c) VT420 / 4-20mA converter
The converter of direct current 4-20mA is used for measurement of constant current on 4-20mA from different sensors and converting data into the format of the IP monitoring system. The sensor is connected to the Vutlan monitoring system by RJ11 / RJ12 cable and detected by the system automatically.
d) Vutlan monitoring system
The system interface allows you to assign the sensor and to introduce the function data conversion.
Example 1
Industrial water level sensor is monitored by VT335 monitoring unit
- The sensor’s data is sent to Network Monitoring Center using SNMP traps.
- The monitoring unit has built-in logic schemes to send E-mail and SMS messages in case of emergency.
- A technician monitors the sensor using a built-in web interface.
Example 2
Example 2: three pressure transmitters are monitored by VT335 monitoring unit
Same logic as Example 1, but with an additional number of 4-20mA monitored sensors.
Vutlan Web Interface
for monitoring 4-20mA current loop sensors
It is very easy to connect and configure VT420 with 3rd part 4-20mA sensors. Below are some easy steps.
Step 1:
VT420 is detected by the system.
Step 2:
Open VT420 configuration
Step 3:
Tune VT420 and save settings
Step 4:
Sensor is tuned