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What is a 4-20 mA current loop?

The 4-20 mA current loop has been the standard for signal transmission and electronic control in control systems since the 1950's. The 4 mA to 20 mA current loop is a common method of transmitting sensor information in many industrial process monitoring...

Convert 4-20 mA to 0-10 V using a resistor

All iSMA Universal Inputs cannot read a 4-20mA signal directly, so to read a 4-20mA sensor you will find in the box of every iSMA device (with Universal Inputs) a set of 200 Ohm resistors. It is extremely simple to measure 0-20 mA analog signal from a sensor with a...

Niagara AX to N4 Migration Guide

To use the Migration Tool provided by Tridium you will need a backup(dist file) of a station that is running on AX 3.8, |You cannot migrate only the bog file or a station running a version lower than 3.8. Backup the AX station If you need to include the alarms and...

Startup guide for the MAC36NL

Connecting and configuring the device 1) Power supply You can use 20Vac to 28Vac or 20Vdc to 28Vdc The power required depends on whether you are powering in AC (24VA) or DC (14W). A dedicated UL listed, Class 2, 24Vac transformer/24Vdc power supply with 1 amp capacity...

Free Building Management System Software Tools

Often the controls manufacturers provide you with all the tools required to get the job done, but there are certain situations where you need to use 3rd party software or websites for certain tasks. I have a go-to set of trusted software solutions that I use time and...

BMS Engineers Bonus Carry Items

Here are 5 items that I hate going without when commissioning any project. These are not your typical items such as screwdrivers and multimeters, these are bonus items, items which are going to make your day much easier but they wouldn’t be a showstopper if you didn’t...

BMS inputs & outputs

This is BMS 101, if you can clearly identify your inputs and outputs then you are going in the right direction. A key thing to understand in the world of BMS is the difference between inputs and outputs, often referred to as IO. Most of you will probably be thinking...

Modbus Basics for Building Management Systems

I am going to start off by saying that I am no expert with the Modbus protocol and there are many of the more technical aspects of it that go way over my head. Having said that, when using Modbus in the field, the finer, more technical details of the protocol are not...

Advanced BMS Logging with Tridium

Make BMS History points to the next level with Tridium. The standard history information for points within any Tridium station is already very powerful, provided that you have some way of exporting it and / or storing it you can have access to unlimited data. But...
What is a 4-20 mA current loop?

What is a 4-20 mA current loop?

The 4-20 mA current loop has been the standard for signal transmission and electronic control in control systems since the 1950's. The 4 mA to 20 mA current loop is a common method of transmitting sensor information in many industrial process monitoring...

Convert 4-20 mA to 0-10 V using a resistor

Convert 4-20 mA to 0-10 V using a resistor

All iSMA Universal Inputs cannot read a 4-20mA signal directly, so to read a 4-20mA sensor you will find in the box of every iSMA device (with Universal Inputs) a set of 200 Ohm resistors. It is extremely simple to measure 0-20 mA analog signal from a sensor with a...