What is a Solar Powered 4-20 mA Transmitter

Solar Powered 4-20 mA Transmitter

An off-grid solar power system allows you to install and operate a 4-20 mA Transmitter in locations where a traditional 120VAC or 24VDC wired power source may be impractical, expensive or not available. Solar power systems can be the perfect solution for saving money powering 4-20 mA transmitters in remote locations.

For remote industrial process control instruments, solar powered analog 4–20 mA current loops are commonly used for analog signaling, with 4 mA representing the lowest end of the range and 20 mA the highest. The big advantage of the solar powered current loop is that the accuracy of the signal is not affected by voltage drop in the interconnecting wiring, and that the loop can supply operating power to the device. Even if there is significant electrical resistance in the line, the solar powered current loop transmitter will maintain the proper current, up to its maximum voltage capability. The live-zero represented by 4 mA allows the receiving instrument to detect some failures of the loop, and also allows transmitter devices to be powered by the same current loop (called two-wire transmitters). Such solar powered 4-20 mA transmitters are used to measure pressure, temperature, flow, pH or other process variables. A solar powered current loop can also be used to control a valve positioner or other output actuator.

Solar Powered 4-20 mA Transmitter System

A solar power system for a 4-20 mA transmitter consists of a solar module, a solar charge controller, a rechargeable solar deep-cycle battery, power converter, regulator or inverter and a weather-proof outdoor enclosure. This system is used to collect solar energy and the store electrical power, and then convert the stored power into the correct voltage to operate the 4-20 mA transmitter.

What Size Solar Power System for A 4-20 mA Transmitter?

Solar 4-20 mA Transmitter System

To select the correct size solar power system to power a 4-20 mA transmitter there are a few things that must be known.

  1. What is operating voltage and power consumption in amps, or watts of the 4-20 mA transmitter?
  2. How many hours each day will the 4-20 mA transmitter be required to operate.
  3. What is the geographical location the solar powered 4-20 mA transmitter will be installed.
  4. How many days of battery reserve power are desired for "no sun" days?

If you need help sizing a solar power system for your application, please contact us.