Week 9 Update - Current Transducer and BASpi

 

Hello

Remember last week when I was using that Current Sensor and neither I nor my professor could figure out and get working? We blew it and we're still going to blame it on the lackluster documentation.

Now, today I got the same Current Transducer I used in Week 6. Got a Light Bulb, Electrical Cord, and hooked it up exactly as I did before. This time the bulb I used was a 40 Watt so this means that 40 Watts/120 Volts = 0.333 Amps. On my Multi-Meter I got a reading of 134.0 millivolts which I then multiplied by 0.001 to get 0.134 Volts then multiplied that by 2 to get 0.268 Amps. This is not too far off from the 0.333 Amps I calculated earlier, and you would see a similar value on a Clamp-On Meter. I've included pictures of my setup:

I then hooked up my BASpi and here is the set up. I know it's messy as I had to get my breadboard out so that the Current Transducer, Multi-Meter, and Universal Input wires would all go to the same place.

By the way I just wanted to let you that I had to play with my Tablet's Ethernet settings. Why? Well, the default IP Address of your BASpi is 192.168.92.68 which means I had to change my Tablet's Ethernet settings to:

IP Address: 192.168.92.69
Subnet Mask: 255.255.255.0
Default Gateway: 192.168.92.0

Afterwards I access the the BASpi web page and his a screenshot. My Multi-Meter still reads 134.0 millivolts, but on BASpi I'm getting 0.109 Volts and not 0.134 like in my calculations and I don't know why.

Here are some screenshots of the Virtual Points I used, as well as, a screenshot of Sedona showing the program I made.

Now, I will explain my program. So, my Universal Input 1 which is my Current Transducer is feeding in 0.10 Volts into a Multiplier. I used a Virtual Point with the value of 3 in so 0.10 multiplied by 3 would give me 0.32 which is my Mutli-Meter reading. This was great, but I ran into a problem. In my calculations, I would multiply the Voltage by 2 to get the Current, which I did feeding my 0.32 and a second Virtual Point with a value of 2 into another Multiplier to get 0.65. According to my calculations, I'm supposed to get 0.268 Amps. I'll give this another try next week. Bu then I will have figured something out. I'll even ask one of my classmates for advice.

Here is an alternative way to setup the jumper wires on the breadboard:

- Valentin