Pictures of completed Desalination Machine

Pictures of completed Desalination Machine

Final Wire Terminations and Testing

Final Wire Terminations and Testing

Date: 5.22.18 and 5.24.18
Location: Logan HS
Time: 5 hours
Students: Dom and Thomas Kujak
Goal: Make final wire terminations, wire solar panel and work out voltage issues on the micro motor vibrators.

We had another work night after school to make the final connections. The fuse box now looks much better without all the wires hanging out of it.

The 555 timer circuit had to be redesigned because the output was only designed for one motor. Some parallel resistors were added to the circuit and we changed around some outputs and it now works well with four motors. Dom resoldered much of the circuit to make it functional. Andy K. did the orginal design which helped us get to where we are now with it.

The design of the solar panel circuit was discussed and we decided to wire it straight into the box rather than direct to the battery. We will have two 10 amp fuses in that circuit. We did some initial testing and the power on LED in that circuit still did not want to work so we need more time to troubleshoot it.

If you scroll down to the bottom of this page you can view one of the more important videos of this project. We completed our pump test. We have three pumps (Evap. Circulation, Condenser Circulation and Evap. Tank Pump) and we needed to see how well they controlled the water flow and if we had any external leaks. We did have some leaks which forced us to tighten and add a few more hose clamps, but we had it under control in a short period of time. We also found two electrical wiring problems (pumps wired to the wrong switch) and corrected that.

The way the system is wired and fused after we did some re-wiring is the Evaporator Tank Pump and is on the Evaporator Peltier #2 Switch sharing the same fuse. The Evaporator Circulation Pump is on the Evaporator Peltier #1 Switch sharing the same fuse. The Condenser Circulation Pump is on the Condenser Peltier #1 Switch along with the Circulation Fan sharing the same fuse.

In our inital tests we were able to move water and control flow very well. Now we need to do a longer system test to see if we can produce water clean. This will come after we get a new 12 V battery because the one were were trying to use will not keep a charge.

A quick look at time spent on this project puts us at about 225 hours right now. The vast majority of that is after school time.

Final testing on the DM project will be next week.

Raw materials needed to build junction box for solar panel.

Completed box with plexiglass top. Fuse, switch and LED fabricated into the top cover.

Working out wiring up to solar panel (14 V) and battery (12 V). This proved more challenging than expected.
The circuit has two power sources feeding into it. The LED would stay on no matter what the switch position
was. Using two switches will work but we are looking at adding a diode or resistor to simplify.

Thomas starts to disconnect the outputs for the motor vibration units in the condenser.

Seeing the power indicator light go on on the motor vibration circuit is always reassuring.
This unit will then be mounted in the circuit box.

Testing the pumps to check water flow and control.

Work Night Mounting Arduino, Thermistors and More Wire Termination

Work Night Mounting Arduino, Thermistors and More Wire Termination

Date: 5.17.18
Location: Logan HS
Time: 4.5 hours
Goal: Mount/install the Arduino temperature measurement system and terminate the rest of the wires.
Students: Boy Yang, Matt, Ian and Dom

We should have known things were going too well. Wire termination went slower as new students were learning how to crimp and terminate wires in the box. We had two connections that were not properly terminated and had to be re-done (wire was loose in the fork connector). We also had a labeling issue on our pump controllers that forced us to troubleshoot the connections for about an hour and our 12 V battery died (it needed to be charged anyway as it was low to start). We noticed one of the 12 V fans on our large peltier stopped spinning and we were not sure why until we found out the battery was only outputting 9 V. We think this is why some of our pump tests did not work later in the evening also.

On the positive side, our LED's all work and we think we have the Arduino temperature sensing controls installed. We ran thermistors sensors to the tanks and supply lines into the DM at four predetermined locations. We want to assess the water temperature in the circulation lines entering both tanks and also sense the air temperature entering both tanks. We did not have time to test it, but we will do so tomorrow.

We still have some concerns with the pumps. We want to run 12 V directly to the pumps from an external power supply to make sure they are all working. If they are, then we know the system will pump and circulate water and any further troubleshooting would have to be in the switch or control areas.

Vinyl stickers were designed and made with our vinyl cutter to identify different components on the DM. They really make the DM look more professional as they are color coded.

We did not terminate the micro vibration motors yet but we have them powered. This was just a time issue and we wanted to make sure we had the correct inputs and outputs on the 555 timer circuit that they will go into. Once that is complete, all wires will be terminated.

In another brief update, on Friday we hooked up the micro vibration motors to test them. The circuit worked with one in place, but voltage was divided when we added another. We are wired in parallel and may just need to increase our amperage. Before we do that, we want to make sure our circuit is designed for 4 motor vibrators.

Also, the Arduino and thermistors performed well in our first test. Andy needed to make a few changes to the code to display all 4 thermistors with labels on locations. It worked well after that.

Next goal will be to start testing the system with water running through it.

Matt installing the wiring for the Arduino.

Students learning how to crimp wire connections. We normally solder all of these, but due to the small space
in the electrical box, we needed to just crimp.

The black wire in the bottom of the pipe is a thermistor (one of four) that were installed. They are wired
back to the Arduino and then a display. This monitors the air temperature going into the evaporator tank.

Boy Yang powering up the system for a test.

Looks like a mess of wires, but much better than two days ago.

Terminating Wires and Connectivity Test

Terminating Wires and Connectivity Test

Date: 5.15.18
Location: Logan HS
Time: 3.5 hours
Goal: Terminate wires from switches, pumps, peltiers, etc... in box and complete a connectivity check.
Students: Boy Yang, Austin, Ben and Andy

This was one of those significant work nights where we are beginning to see the end in sight. We started terminating wires into our electrical box which indicates we are not far from a test of the DM prototype.

A lot of front end work went into identifying each of the 70 wires coming down into the box. This was done with labels and masking tape. All the common wires were identifed and terminated first. Then we started work on the individual pumps and fan. We are working in "layers" putting multiple loads on each circuit breaker. For example, on one 10 amp breaker we will have the evaporator tank pump, and evaporator peltier all tied into the same breaker. All total they do not exceed the 10 amp draw. This will save us some time and space.

We had two people organizing wires, cutting, stripping the wire and then crimping a fork onto the wire to secure to the bus or terminal strip. It was very tedious work, but at the end of the night, we energized the circuits we completed and we did have connectivity.

We will do another work night on Thursday to finish the job.

Ben fabricating some barrel connectors.

Ben and Andy terminating wires in box. 

2nd shift work crew (Boy and Austin) watch and wait to switch in to help out.

Only about 15 wires to terminate!

Students working in a tight area to connect wires.

View from the top down to see work on the circuit box continued.

Soldering Connections and Fan Mount Fabrication

Soldering Connections and Fan Mount Fabrication

Date: May 7-9, 2018 & May 10th, 2018 (Work night)
Location: Logan HS
Time: 7 hours
Student: Alex, Paige, Austin, Dom, Boy, Lam, Joel, Simon and Ben
Goal: Get electrical box ready for wire terminations, run wire and complete fan module.

Students have been working during and after school on a variety of projects related to the DM. For example Lam has worked out a neat shirt design that we hope to have done in a couple of days. Others have been soldering wire connectors, shrink wrapping, mounting more switches and making strings of LED's.

We hopefully completed the fan mount today and tested it. The fan runs well at low speeds, but when we speed it up it begins to vibrate. We feel this is because the plastic screen grid we cut for inside the pipe has not been glued in yet. This was done today so we hope it stabilizes it at top speed.

The number of wires running off the DM are both impressive and daunting because they all have to be terminated properly for the machine to work.

May 10th - Work Night

Wires, wires wires...we worked on running about 70 separate wires into our fuse box. This was quite a job because each wire pair had to be labeled and run through conduit or directly into the box. We are using heavier 8 gauge wire from battery to circuit breaker and then to the fuse box. All other wires gauges vary in size (depending on ampere draw of load) from 14 gauge to 18 (although our thermistors will probably be 22 gauge).

We also had to solder some switches and wire extensions.

Wire termination will take place on Tuesday next week. Then we are hopefully ready for a system test.

Students working together soldering components and wires.

Our circuit box with all the termination bars and bus bars installed. Andy's Micro Vibration Motor
controller is at the top of the picture.

Picture of DM with wires waiting to be run through conduit or directly into
the box.

This is the fan motor assembly test with the support grid cemented in.

It worked well with no vibration.

Simon soldering some wire ends.

Dom working on running some wires through conduit.

This is what 70 wires looks like before they are terminated in the box.
Each one is labeled to indicate origin and some still have to be run into
the box.

Work Night on Spray Module, Wiring & Fan Mount

Work Night on Spray Module, Wiring & Fan Mount

Date: 5.3.18
Location: Logan HS
Time: 3 hours (4:30-7:30 pm)
Goal: Create the spray module, work on wiring, program Raspberry Pi 3 and fabricate fan mount.
Students: Boy, Gabe, Cashew, Andy, Dom, Austin, Ian and Matt.

Good turnout for the work night. Groups were split up to work on different parts of the DM. Work on the spray module for the evaporator went well. The fan mount took a step backwards as the fan shaft still is not square and plum with the motor mount. This is fixable, but it will take time to tweak it and get it right. This part of the DM has taken much longer than anticipated.

Mounting the switches has begun and we made good progress on that. More time is needed to wire in the switches through conduit into the box. More time was taken to calculate the total amperage needed to supply all the components in the DM. The total amperage is pushing 50 amps as we continue to add more to the DM. We will need to get a 60 amp circuit breaker as a master switch.

The overall good news is when the wires start running from the switches, we are getting closer to finishing as that is the last step before testing the system. The best news of the night was Dom got the programming for the Raspberry Pi 3 to work wirelessly with the camera. This will be broadcast over the network so we can see the temperatures via cell phone. We still have some configuring to do, but are close here.

We tried drilling 1/8" holes in the tubing for the spray module but it just clogged up the hole. We used an old soldering iron to place holes in the tubing every 2". This will become our spray head over the evaporator.

Spray module being zip tied in.

Boy and Gabe checking the spacing on the spray module.

Dom working on the programming for the Raspberry Pi 3 camera.

Andy and others getting some pizza while they work.

Austin and Cashew drilling in the holes for the fan mount.

Ian and Matt working on mounting the switches in the control board.

Cashew showing off his work with the fan mount.

Fabrication of Fan mount and Switches

Fabrication of Fan mount and Switches

Date: 5.2.18
Location: Logan HS
Time: 1.5 hours
Students: Alex, Austin, Caitlin and Paige
Goal: Continue work on the fan mount and get the pump and fan controls mounted.

We had a little time to work on the DM today. Paige and Caitlin got some extension wires soldered to the pumps and then Paige and Alex worked on one of the LED lighting systems. They did some Ohms Law calculations and ended up melting down a resistor when they increased the voltage above 12 volts, however, the LED did not blow. This will have to be "redone".

The fan mount continues to be a time consuming process. A lot of time has been spent making sure it will be placed in the pipe centered and square. Holes were drilled in the pipe today and bushings were epoxied in to accept the fan shaft. We hope to mount the fan Thursday night.

Austin in the mean time worked on drilling out the controls for the pumps and fans. We should be ready to wire these in on Thursday.

Paige and Caitlin getting ready to solder some of the pump wires together.

Alex attaching the fan motor to the mount.

A picture of the flexible fan coupling, fan mounting plate and fan motor. We hope the flexible coupling will
help stabilize the unit in case we do not have the holes drilled exactly centered.

The fan will be placed on the end of the shaft in this picture. The plastic mesh supports the fan where the fan
shaft runs through the bushing. We just epoxied the center of the grill and then drilled a hole through it for the bushing.

Austin placing the switches in plexiglass control panel.

Beginning to label the switches for wiring.