Hi all.
I am not very clued up with electronics. I am a mechanical engineer and did study some electrical engineering subjects at uni but that was awhile ago and I didn't do that well at the subjects back then.
Anyways, I am busy trying to get my masters degree and I have built an experimental setup which investigates heat transfer in water. I am not going to explain my project or setup in detail but I will try to give enough detail to my problem as I can.
I am using n type thermocouples to perform temperature measurements. These thermocouples are located very close to a 2500W / 230v AC heater element. These thermocouples cannot be shielded or moved away from the heater due to space limitations.
I have a problem with electromagnetic interference from the heater as one would expect. The readings from the above mentioned thermocouples are definitely influenced by the heater when it's switched on.
I am using an agilent data logger to measure voltages from several pressure transducers and thermocouples in my setup every 2.13s. These measurements are then sent to a pc running labview in pulses. I am using labview to post process my results but I am not currently using labview in any way for control.
My solution would be to create an arduino / Mosfet setup which would turn the heater off, take a measurement from the thermocouples, then turn the heater back on. This would happen relativly quickly and timing would need to be important hence the inclusion of the arduino for control. As the heater is AC, I will have to include a bridge rectifier.
So this is where I stand. I am afraid of blowing the arduino & pc if the circuit is not correctly designed as the current is fairly high in the heater. Is there any advice that you can think of? I have never designed my own electrical circuit before.
I am not very clued up with electronics. I am a mechanical engineer and did study some electrical engineering subjects at uni but that was awhile ago and I didn't do that well at the subjects back then.
Anyways, I am busy trying to get my masters degree and I have built an experimental setup which investigates heat transfer in water. I am not going to explain my project or setup in detail but I will try to give enough detail to my problem as I can.
I am using n type thermocouples to perform temperature measurements. These thermocouples are located very close to a 2500W / 230v AC heater element. These thermocouples cannot be shielded or moved away from the heater due to space limitations.
I have a problem with electromagnetic interference from the heater as one would expect. The readings from the above mentioned thermocouples are definitely influenced by the heater when it's switched on.
I am using an agilent data logger to measure voltages from several pressure transducers and thermocouples in my setup every 2.13s. These measurements are then sent to a pc running labview in pulses. I am using labview to post process my results but I am not currently using labview in any way for control.
My solution would be to create an arduino / Mosfet setup which would turn the heater off, take a measurement from the thermocouples, then turn the heater back on. This would happen relativly quickly and timing would need to be important hence the inclusion of the arduino for control. As the heater is AC, I will have to include a bridge rectifier.
So this is where I stand. I am afraid of blowing the arduino & pc if the circuit is not correctly designed as the current is fairly high in the heater. Is there any advice that you can think of? I have never designed my own electrical circuit before.
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