# Load cell Interface with PLC



## cmdr_suds (Jul 29, 2016)

balajiraja said:


> In my project we are using load cell for monitoring the weight of the unknown materials, and this load cell is interface with PLC for process control system. So we need circuit diagram for this load cell converter circuit of 4-20ma to the PLC...


Is my understanding correct? You already have a 4-20mA signal from the load cell transmitter and you need to get that signal into a PLC that does not have an analog input? Try this:

http://www.sensorpulse.com/Downloads/ProductSheets/mspcin_bull_rev2003.pdf


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## oliquir (Jan 13, 2011)

check for strain gage tranducer the will accept loadcell signal and convert it to 4-20ma
here one cheap china one
https://www.aliexpress.com/item/Pre...rce-measurement-balance-load/32399220829.html


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## varmit (Apr 19, 2009)

The load cell output will be a millivolt analog, usually 0 to 30 millivolt. If you have a analog input card with enough resolution, you could set the input card to voltage input and connect the millivolt signal direct to the PLC. If this is not an option, a signal converter for millivolt to 4-20 is an off the shelf item.


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## triden (Jun 13, 2012)

Buy a weighing module for your PLC. Most of the major manufacturers have one.


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## wise119 (Mar 10, 2016)

balajiraja said:


> In my project we are using load cell for monitoring the weight of the unknown materials, and this load cell is interface with PLC for process control system. So we need circuit diagram for this load cell converter circuit of 4-20ma to the PLC...


How many load cell do you have, any protocol you prefer? Most PLC can handle load cell/ strain gauge input. :thumbup:I personally like using modbus PLC/PAC to read any analog input or 4-20mA input. I used a device ET-7016 to read strain gauge input and send data directly to my SCADA software. 
https://www.icpdas-usa.com/et_7016.html


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## John Valdes (May 17, 2007)

I need some money as well. Thanks in Advance.


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## sparkiez (Aug 1, 2015)

Get you a weight indicator with a 4-20mA output to the PLC. The advantage of using a weight indicator in a situation like this is pretty great. I know a lot of people like to use little boxes because the indicators tend to be a little more, but indicators are made for the purpose of reading a load cell and have built in options to keep your scale zeroed, troubleshooting functions for the load cell and all kinds of other options to keep the scale stable and happy during your process.

This also cuts down on the maintenance issue. They can go to the load cell and troubleshoot the scale itself, perform calibrations, etc with minimal training and know right off the bat if the problem lies in the scaling or in the output signal.

Using a load cell module is also a great option, the only downside being you have to handle the indicator functions in the logic itself, and these tend to be more expensive than an indicator (which you can get for a few hundred bucks).


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