adccommunitymod (AutomationDirect) asked a question.
Created Date: July 03,2018
Created By: dionysius
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i am building an application to stir some materials at a fixed & known RPM. i would like to monitor and record torque through the procedure and then shut down the process at a fixed torque as the material viscosity increases to a established 'set-point '. i have envisioned a variable speed DC motor controller (with digital speed setpoint), a DC motor, a futek (or equivalent) torque sensor and a torque switch, driving the agitator. a data logger would record rpm speed, voltage, amps, torque, & process temperature. i would appreciate any alternative easier, simpler, more elegant suggestions. thanks
Created Date: July 03,2018
Created by: dionysius
i am building an application to stir some materials at a fixed & known RPM. i would like to monitor and record torque through the procedure and then shut down the process at a fixed torque as the material viscosity increases to a established 'set-point '.
i have envisioned a variable speed DC motor controller (with digital speed setpoint), a DC motor, a futek (or equivalent) torque sensor and a torque switch, driving the agitator. a data logger would record rpm speed, voltage, amps, torque, & process temperature. i would appreciate any alternative easier, simpler, more elegant suggestions.
thanks
Created Date: July 05,2018
Created by: strantor
How many are you making?
I ask because, you will need to measure torque by some means to correlate with amps, if you want to go the torque:amps route. This will probably require the purchase of a torque measurement device and the fabrication of a torque measurement fixture.
if you 're only making one unit, just make the device and the fixture part of the machine and be done with it. If you 're going to manufacture multiple copies then it would make sense to purchase the device and fixture only once, and use it develop an algorithm to convert amps to torque.
Created Date: July 05,2018
Created by: dionysius
thanks for the input. at this time the intent is for a one time device. a torque sensor would be necessary to calibrate the amp/torque ratio value. may as well leave the sensor as an integral part of the design.
Created Date: July 03,2018
Created by: Tinker
Theoretically the torque of a DC motor is directly proportional to current. In the real world there may be some errors du to various factors, but it will generally still be pretty close. Depending on the accuracy you need, simply measuring the current might avoid the need for the (probably expensive) torque sensor.
Created Date: July 05,2018
Created by: dionysius
is the "current proportional to torque " valid for only one voltage (i.e., rpm) or does the proportionality hold up at a variety of different speeds?