My Medium Sized DIY Cage

[mlwinters]

Hey everyone, I thought I would share some details and pictures of my custom built cage for a syrian hamster.

The inside dimensions of this cage are 1470mm by 507mm giving a floor space of 7434.09² cm when taking into account the two vertical supports and 533mm high.
These two supports reinforce two shelves and also holds the acrylic panels upright and against a wooden strip along the bottom front edge. The acrylic panels are joined with a PVC joiner thing, this allow the two panels to be easily and quickly removed.

The cage has three doors, two front doors that open out and the lid/roof that lifts up, it also has locking wheels to allow easy movement. The castors have a foam pads to help reduce vibrations traving into the floor (live in second floor flat). It has three shelves, the lower two shelves are at the same height (~200mm) and an upper shelf (~350mm) with steps on one side and a staircase on the other. I took inspiration from a popular YouTuber for protecting from falls by using around 300 ice lolly sticks to fence off around all shelves, each one was individually glued and placed, indeed this took ages to get right. The edges of the shelves and steps are cladded with balsa wood as with the back of the stairs. I have used at least 50mm of bedding around the wheel and with most places between 75 and 150mm, both for cushioning falls and for digging/tunneling in. Maximum depth of bedding is upto 190mm at the front.
I have put three pull tight latches on the doors, one between the two front doors and the other two on the roof, one on each door. The doors also have magnets on them to hold them closed. Both the doors and roof are very secure when locked
I have fitted three 12V warm white LED strips, one to the roof and one to each end wall at moreless a 45° angle. These LEDs are running at 10 volt to reduce the overall brightness and power consumption. This is something I want to change in future though, I'm not happy with these lights.
The black, well red square thing bottom left of a piece of very dark red lighting gel. Behind is a nest box that the purple tunnel goes to. The LX gel only allows 4% light to travel through and is almost pitch black inside even on a bright day.

Its probably best if you see some photos. I have made a few changes since these were taken, placement of toys, more toys, bigger and better food dish ect but you get the idea as to the construction and basic layout.
Please let me know what you think and let me know if I need to change anything.

There are a couple of things I haven't mentioned in here but Ill save those for another post, another day.

Take Care
Morgan

P.S. Please discount the sticks poking up like spikes, I was trying something out unrelated and was using the bedding to hold them in place. I forgot to remove them for these pictures. These sticks are, as they are here, clearly very dangerous. No animal is living in or indeed anywhere near the cage. Its just that these pictures are the best I have.

P.S.S. Sorry if this is in the wrong place, mods please move if it is.

[SKB_Hamsters]

Your DIY cage looks amazing and very spacious!

With the LED lights do you have them on at night when watching your hamster? As I you do I would recommend Red LED lights instead as hamster can't see very well in the red end of the light spectrum therefore allows us to watch them without disturbing them too much and you can get to see what they really get up to when they think no one is watching.

[mlwinters]

Your DIY cage looks amazing and very spacious!

With the LED lights do you have them on at night when watching your hamster? As I you do I would recommend Red LED lights instead as hamster can't see very well in the red end of the light spectrum therefore allows us to watch them without disturbing them too much and you can get to see what they really get up to when they think no one is watching.

Thanks for your kind words.
I am quite pleased with how its turned out, it is way better than what I thought it would be when I started on this project. I heard people say to get the biggest cage you can and this was indeed the biggest I could get away with without making my room look too cluttered. Any bigger would have also increased the price of materials by more than I wanted to spend on it, this cage wasn't the cheapest to build as it is.

As I said in my first post, the lighting is something I am not happy with and will be changed soon. This is one of the few errors I made designing this cage and will be done and redone untill its right. Im planning to replace either the centre strip or the two outer strips with red LEDs. I've been trying to find LED chips that are half way between visible red and infrared to reduce the amount to green and blue light as much as possible but this ain't easy with the LED's I want coming on reels or either 1000 or 5000, I don't need quite that many. I have found some which I'm going to order soon. These LED's have to be a specific surface mount chip due to the trunking that the LED's are mounted in. The new LED's would then need to be soldered to a flexible LED strip. Replacing the LED's isn't a complx job, its just time consuming and fiddly with such small LED chips. If I used larger 3 or 5 mm through hole LED's, they would protrude through the trunking, stick out, look ugly and if the hamster bit one of the lens, it could shatter spraying tiny chunks of plastic everywhere and expose live terminals (all be it 10 VDC). This is not something I deem to be acceptable. The current LED's are moreless the same height as the thickness of the trunking's plastic and sits almost flush with the trunking reducing the above issue substantially.
Currently the lights are set to come on at 1630 and turn off at 2330, however they can be made to switch at whatever time I choose (within 1 second) and these times are only for testing everything. They can also be turned on/off at any time manually.
Once I have completed this upgrade, I plan to use the warn white lights as a day lights and for when I need to do a spotclean or full cleanout ect since those will be done at night when the hamster is awake. Red LED's will be on during normal night time hours.

Indeed, the point you are making is a very good one and highlights one of my design errors. It is something I'm working on and should be done within a week or so, I won't be happy untill the lighting looks right (that's what happens when you play with theatre lighting for almost 20 years :-P).
Rest assured, I am working on it as fast as finances and Royal Mail allows :-D

Thanks for your feedback
Morgan

[Dedenne]

That is wonderful! One of the nicest looking I have seen
This one definitely goes into my ”cage idea” book!

[mlwinters]

That is wonderful! One of the nicest looking I have seen
This one definitely goes into my ”cage idea” book!

Thank you, I am pleased with how it's turned out :).
Feel free to get ideas from or copy it if you so wish. Ill be posting a lot more in the coming days so stay tuned :D.

[mlwinters]

As promised, here are some more details about my cage, although just a mini update this time.

During my research into hamsters and hamster care as I was building the cage, I found out about torpor. Although not always fatal, I simply didn’t want to take the risk. Being the type of person who prefers to use a hot water bottle and multiple layers of clothing to warm themselves up rather than having expensive nightstore heaters turned up high, my flat can sometimes get to or sometimes go below the point which torpor becomes more likely. One way to help reduce the risk is to ensure the cage temperature is above ~16°C, therefore I have fitted the cage with a digital temperature sensor. Although not the reptile types found at pet shops. The cheaper versions simply tell you the temperature and nothing else, they don’t always have an alarm if the temperature is outside of a predefined range. Plus being for reptiles, this range may not be right for a hamster if its factory set and not customisable.

The sensor I have chosen is an Adafruit BME280 sensor. It is powered from between 3.3 and 5 volt DC and uses I²C, a digital serial interface, to communicate with a controller (details on this to follow). The sensor can give temperature in C or F, relative humidity and air pressure in pascals which is then converted into milli-bar and then pounds/square inch (pressure is also altitude compensated). All readings are accurate to within 10 decimal places, although the readings are rounded to 2 decimal places for my use. The sensor can be read more than 10 times a second, exact speed is unknown, I don’t need anything faster. In normal use, it’s only read once a second.

The sensor is mounted inside of a vented ABS plastic case which is screwed to the underside of the curvy shelf to prevent the hamster from accessing to. The L shaped, right side shelf is cut short to reduce access further. This is one reason for having fencing in the bottom sheves along with safety and to match the top shelf. I have mounted the case as close to the back wall as possible while still allowing for the cover to be removed. There is no exposed wiring between the sensor case and the back wall where the cable exits the cage that the hamster could chew into. The sensor is soldered to a second circuit board which is then mounted to the plastic case with standoffs to reduce short circuits, mechanical stress from the screws on the sensor’s printed circuit board and gives an air gap between the second circuit board and the plastic case to reduce the chance of inaccurate data. The wiring is tied in a loose knot to limit the chance of the cable being ripped out of the second circuit board if the cable at the back gets caught on something, the knot will tighten and get pulled against the sensor case and hole in the cage back wall before it pulls the wires out of the circuit board. This is common place in electronic products and does not affect the sensor in any way.

As I said, this is a mini update just to show you the sensor and its placement. What happens with the data it outputs will be in a later update. Enough blabbering, here are some pictures.

44784
Sensor as it was delivered.


44785
Placement of sensor case within the cage.

44786
With cover removed


Let me know what you think.
Take Care
Morgan

[mlwinters]

P.S. There some random forum bug thats messed my last post up and its not letting me fix it properly. Sorry about this.

[mlwinters]

Time for another update and this one is right up my street, lighting :D

As pointed out in my first post, the lighting wasn't something I was happy with. I have finally ordered the replacement LED's for the cage lighting and have upgraded all three LED strips. Thanks to SKB_Hamsters, each LED strip now has warm white, red and one other colour. The LEDs are again in groups of three LED's connected in series. Each white LED group each has a 56ohm resistor, each red group and each other colour group both have 120ohm resistors. Each colour has a supply voltage of 10VDC and all LED groups in each strip share a common ground to reduce the amount of wiring thus failure points. The upgrade process itself took a couple of weeks due to this being the first proper time I've desoldered and soldered the 3528 surface mount LED's. Being so small and not having magnifying lens or microscope, it was quite tricky and time consuming. Each group is super glued into the strip and hot glue was used to act as a strain reliever, mainly for the centre strip which is fixed to the roof and therefore it would put stress on the solder joints when opening or closing the roof, the hot glue minimizes this stress, both outter strips have hot glue to minimized this stress during installation but serves no purpose now. Each strip was left in my living room for at least 2 days for the fumes of the super glue to disperse (cage is in bedroom). The trunking around each LED hole was also sanded to remove as much of the dried super glue on the exposed side as possible to minimize the chance of ickle one injesting it. Most of the LED's aren't accessable but they were still cleaned off anyway.

Each of the strips have a slightly different colour sequence and are as follows, starting from the back of the cage to the front:
Left side: White - Red - Other Colour - Red - Blank
Centre: White - Other Colour - Red - Other Colour - White
Right side: Blank - Red - Other Colour - Red - White
(Blank means there are no LED group)

All three colours are switched on/off automatically by the controller between the following times:
White: 10:00:00 - 16:59:59
Red: 17:00:00 - 23:59:59
Other Colour: 00:00:00 - 09:59:59 (but only if a certain condition is met)
Full details of the other colour will be released soon.
The lights are switch to within one second of these times (less if I really wanted the accuracy) and can easy be changed to what I want.

Each colour can of course be switched on/off manually if needed however, one can only switch colours. Each LED, group or strip cannot be switched individually. The power supply is able to power all three colours at the same time but there are two seperate safeguards in place to prevent this from happening. More details will be in future posts.

The switching itself is currently done as a snap change, in other words, the LED's are either on or off. This is the next this I need to work on as I am not happy with it as its, from an engineering viewpoint, ugly. The LED's are currently connected to a relay (a mechanical switch using an electro-magnet to move a magnetic switch plate), this is far from an ideal solution due serveral factors, an audible "click" when the switch plate moves, vibrations and power consumtion (each coil pulls around 50mA at 5V). The use of a 3 amp relay was always a temporary solution until I knew the power consumtion of the cage lights.
I have re-designed an upgraded switch board that use medium power transistors (electronic switches) for each of the lighting circuits. This will eliminate the audible click and vibrations. This upgrade will also reduce the power consumtion down to less than 1mA at 5V.
Doing this will also allow me to fix the snap change issue with the LED's so that they crossfade (colour X will slowly fade up while colour Y fades down). Ill go into more detail in a later post about this. I will be making and installing the upgraded switch board over the next couple of weeks.

Enough text, picture time:
45486
White Lights

45484
Red Lights
(my stills camera hates taking photos in red light, these are the best it could do)

The other colour is not shown as they serves a different purpose. As I've said, Ill post full details of this soon.

Sorry the photos are a little small, I didn't want to clog up the forum or mess up the layout.

I hope you like the upgraded cage lighting as much as I do (ignoring the lack of crossfading).
Morgan

[SKB_Hamsters]

The light for you DIY cage look really good and it lovely how you have them on a timer to switch at different times. I too find it very difficult to take photos with the red lights on!
I don't have good knowledge on electronics but it was interesting to read about the step you took to assemble your lights.

[mlwinters]

The light for you DIY cage look really good and it lovely how you have them on a timer to switch at different times. I too find it very difficult to take photos with the red lights on!
I don't have good knowledge on electronics but it was interesting to read about the step you took to assemble your lights.

Thanks I'm glad you like it. I took ages to get right but the end result is worth it.

"a timer", yeah.....it's a bit more complex than that hehe :P

The electronics for the lighting is actually quite simple, a low power transistor switching a relay. The magic happens inside the controller. All will be revealed soon :D

[dreamtree1234]

WOW, this cage design and lighting system is any ham's and hamparents' dream come true! You did an incredibly awesome job with all of it. Thanks for sharing your masterpiece and all of the step-by-step instructions on lighting assembly with all of us. You are truly creative, and I'm sure your ham will thoroughly appreciate all of your hard work and creativity. :) I look forward to the great reveal soon, lol. ;)

[mlwinters]

WOW, this cage design and lighting system is any ham's and hamparents' dream come true! You did an incredibly awesome job with all of it. Thanks for sharing your masterpiece and all of the step-by-step instructions on lighting assembly with all of us. You are truly creative, and I'm sure your ham will thoroughly appreciate all of your hard work and creativity. :) I look forward to the great reveal soon, lol. ;)

Awww, thanks dreamtree1234, that is so kind of you. This comment has turned my ok-ish week into a great one. Thank you :D

Your welcome. Originally I had planned to build a simple cage and without sharing it but with autism and ADHD comes a continuous stream of a million ideas a second, this kind of thing is the consequence of a brain that never shuts up.

I may be teasing a little here but, I'm the lighting is only scratching the surface. The project so far is about 85% complete so there's lots more work still to do. What you've seen so far is only like 20% of it.

Thanks again for your kind words dreamtree1234.
Morgan

[flowerfairy]

I really like your thoughtfully designed cage. It looks spacious and easy to access.

[mlwinters]

Although it may not seem like it, so far my posts on this project have been quite simple. However, from this update onwards, things are going to get a lot more complex, so grab a cup of tea and a slice of cake...oh and put your thinking cap on too :razz:.

Today I will be talking about the only thing on this project that MUST be 100% correct. The power supply unit which powers the entire electrical system for the cage. This update shows the first of four custom made circuit boards used on this project.

DISCLAIMER: Details included in this post are for educational proposes only. DO NOT attempt to recreate any part of this power supply. Parts of this power supply are connected directly to the building’s mains supply which runs at 230VAC, this level of voltage along with the current available can and will kill you or your pet instantly. I have around 20 years experience dealing with electrical systems as well as electrical qualifications. I possess the required practical and theoretical knowledge to make this power supply in a safe way.
Again, DO NOT ATTEMPT TO RECREATE ANY PART OF THIS POWER SUPPLY.

This power supply is designed to step-down the voltage from 230V, convert the lower voltage from alternating current (AC) to direct current (DC) and then output the different voltages I need for the project, 1.3V, 3V, 5.06V, 10V and 15V.

For various reasons, I will use proper terminology when referring to parts of the electrical system. I will try to add the common name in brackets for the first instance. For example: a lamp (light bulb).
If I miss one or you still don’t know what something is, just ask me.

Low Voltage Side (mains):
The system controller has a flying cable (non-removable) with a standard 13amp plug which is fitted with a 3amp fuse. The cable then goes into the controller’s case through a cable gland which grips the cable and prevents it from being pulled out accidentally possibly causing a short circuit. The outer gray sheathing is then cut back to allow the wires inside to be terminated (attached). The cable is a three core cable, Phase (live (brown wire)), Neutral (blue wire) and CPC (circuit protective conductor (earth) ( yellow/green wire)). The phase wire first goes through a 250volt 0.25amp protection fuse, this fuse is a fast blow fuse meaning that if the current is more than 250milliamp, the fuse will blow and disconnect the power within 50milliseconds (1/20th of a second). The phase wire then goes through an on/off switch (rated at 250VAC at 5amp) and then finally into the transformer. The Neutral wire goes from the input cable directly to the transformer. The CPC is terminated into a round crimp connector. The transformer has a metal bracket around it and has mounting holes at the base. The CPC crimp connector is attached to the transformer with nuts/bolts that attaches the transformer to the controller’s case. This earths the transformer so in theory, if a fault occurs that energises the transformer’s inner iron core and the metal bracket. That power will go through the CPC, through my flats earthing system and into the ground. This will then trip the RCD (residual current device) in my flat’s distribution panel (fusebox) killing the power to the whole flat.
The transformer has a single primary winding (coil) and dual secondary windings. The primary side is rated at 250VAC. Both secondary windings are rated at 15VAC at 1.33amp.
It should be noted here for those who don’t know how a transformer works. There is no electrical connection between the primary and secondary windings, they are indeed completely separate from each other. A transformer uses the continuously varying magnetic field cause by the varying voltage of an AC source, to induce an electro-motive force (voltage although that’s technically the wrong word) into the secondary winding. The ratio between the number of turns of copper wire around the core of the primary winding and number of turns on the secondary windings is what determines the input and output voltages.
For example if the supply voltage is 100 volt, the transformer has 100 turns on primary with 2 turns on secondary, the output will be lets say 2 volt. If there's 100 turns on primary, 50 turns the on secondary, the output voltage will be 50 volt. This is just an example, in reality, transformers will have thousands of turns on each winding. There are also various other factors that determines primary voltage, secondary voltage/current such as transformer type, conductor (wire) thinkness ect.

Extra Low Voltage Side (electronics):
The output of the transformer has four terminals, two for each of the two secondary windings which we’ll call Output A and Output B. I will start with the simplest:

Output A; The phase wire from the transformer goes to a 250V, 1.0amp fast blow fuse before going to the power supply circuit board and into the first "~" pin on the bridge rectifier diode which converts the AC into DC. The rectified supply then goes to a PCB terminal block which the system controller is then connected to, marked as Output 0 on the labelled photo. Further details on where this goes will be in a later post. The neutral wire from the transformer is connected directly to the second "~" pin on the rectifier diode to complete the circuit.

Output B; The first part of this circuit is the same as Output A up to and including the bridge rectifier. It too is protected by a 250V, 1.0amp fast blow fuse. Both of these rectifier diode are rated at 80V 2amp.
However that’s where the similarity between the two ouputs ends. The output or “+” pin on the bridge rectifier diode splits into three traces (electrical pathways or wires on a circuit board). There is a small capacitor here as well which helps to ensure there is a smooth voltage. If the voltage drops for a split second, the capacitor will briefly take over until the voltage returns to its normal level. The capacitor will then recharge ready for the next time. The capacitors have a low amount of capacitance (the amount of energy stored) and will not run any part of the system on their own. Capacitors are not batteries and cannot be used as such.
Each of the three traces then goes to a LM317 adjustable voltage regulator. Along with is supporting circuitry the LM317 steps the voltage down from 15V to the required level, it also tries to maintain that output voltage even if the input voltage drops for a short time. The small blue square things are potentiometers (variable resistors) which are used to set the exact voltage I need. Each output (except output 4) has another capacitor on the output to help filter out any ripples from the voltage regulators. Output 3 has a larger capacitor as the main cage lighting are connected to output 3. Although the LM317’s are rated at 1.5amp each, they still need a heatsink to keep them cool. The heatsinks used are (at least for Output 1) slightly underrated for the current I’m drawing from the voltage regulator. That said, the voltage regulator remains well within its operating range (the heatsink peaks at somewhere around 40-45°C under full load and without the cooling fan, the LM317's have a thermal cut out which is factory set at 125°C).
The output pin of the voltage regulators are connected to a PCB terminal block to the right via underside traces or topside wires. The output voltages are as follows:
Output 1; 3.0V
Output 2; 5.06V
Output 3; 10.0V
Output 4; 1.3V
Pins 5 and 6 of the right hand terminal block are both neutral returns and are connected directly to the "-" pin on the rectifier diode.
Output 4 doesn't have its own voltage regulator, it "piggy backs" off output 1. The lower voltage is down to the voltage drop across the potentiometer and resistor. This can be done due to the power being drawn is less than the resistors rated power (1/2 Watt). The main lighting circuits for example pull to much power to just rely on a resistors voltage drop, hence the need for the LM317's.

The neutral terminal on the transformer's output B is again directly connected to the circuit board and to the second "~" pin on the output B rectifier diode.

As mentioned, I have fitted a 12V 80mm computer cooling fan to ensure that the voltage regulators, the transformer and other parts of the system remains cool. Despite the photos, the fan isn’t directly connected to output 3, I just had it like this while building it and conducting energised tests. The fan is switched with the “other colour” in normal operation and can be switched manually if need. The fan one can see here was just one I had lying around, it has now been replaced with a ball bearing fan which is almost silent.

I have attached four pictures with this post, two of which I have not embedded into the post due to the image size. The schematic is the same as the image embedded, only full size. The other is a labelled version of the photo that's embedded just full size and with labels highlighting the different parts of the power supply.

45724
Photo of the power supply after completion.

45728
Schematic diagram detailing the circuitry.
(please forgive the crude drawing, I do not normally draw schematics)


I should add that I have also since added LED’s on output 0 and output 2. This indicates that the outputs are running and makes it easier to tell if the fuses have blow as well as for system diagnostics. There's a blue LED for output 0, a pink LED for output 2.

As I said in the disclaimer above, DO NOT try to recreate anything in this post. I have posted this information so you can understand what I have created, NOT for you to try to recreate it.


Sorry this is a big update but I feel it’s justified due to its complexity and importance to the project. Sorry too if your brain is now hurting :P.

Take Care
Morgan + Archimedes

[dreamtree1234]

WOW, I am TOTALLY impressed!!!! That is a great explanation of it, too. Thanks for going through all of the details with us. :)

[mlwinters]

Thanks dreamtree1234. That's so kind of you. Once you see the next couple of updates, you'll understand the logic behind my madness. The updates need to be in order though.

Just a quick update, nothing has changed since my last update. I have finally got around to ordering the transistors that I needed to remake the switch board and they came today. I will be making the upgraded switch board over the next few days and will post an update detailing it when its done. Meanwhile, these are the transistor I've been waiting to order. They are 2N3704 N-channel transistors able to switch upto 30V, the maximum current is 600mA and can switch one hundred million times a second (WAY faster than Ill ever need).

45809

I should have the upgraded board installed by the weekend, once installed I need to modify the controller to support to it.

Take Care
Morgan + Archimedes

[StephBrom]

Do you mind me asking what type of mesh you used? And where you got it from? :)

[mlwinters]

Do you mind me asking what type of mesh you used? And where you got it from? :)

It is 12mm steel with a zinc galvanization coating. I picked up four sheets of it from Trago Mills in Newton Abbot, Devon. I can't remember the exact price but they where around £6.50 each. This cage was always designed for a Syrian, a dwarf hamster would need a smaller size mesh.

Hope that helps.

[KarenJoycee]

Wauw your cage is really beautiful! Great job! I luv the big front dores, that just make it perfect!

[mlwinters]

Hey everyone, firstly I must apologise for the lack of updates to this page for such a long time. I have been battling with personal issues and have not been up to posting much content to the internet recently. I hadn't realised until I loggged on here tonight just how long its been since I last posted an update. Again sorry about this.

Anyways, in this update I am going to show you the second of four custom made circuit boards fitted to Archimedes's cage. This is the switch board the controls the cage lighting, system cooling fan and two other things that will be detailed on later posts. This is the third version of this switch board I've made, the first version that was originally fitted to the cage used mechanical relays to switch the lighting, this worked fine but due to the way relays work (basic relays have four pins, two coil pins and two switch pins, when you energise the coil, it creates a magnetic field which attracts a metal plate towards the coil which shorts the two switch pins closing the circuit), there was an audible click whenever the relay was turned on or off, relays are also only able to be switch on or off and at very slow speed.
The second version of the switch board I designed used the transistors I showed in my last update ended up being a failure is I didn't take into account that when I remade the lighting bars, I used a common ground wire (all LED's were connected to the same neutral wire) instead of using a common positive wire. I therefore had to redesign the switch board again to have both NPN and PNP transistors on each switch channel. This added an extra layer of complexity to the switch board.

47711
This is a photo of the finished MkIII switch board after electrical tests and energised tests were complete taken just before installation.

47712
Here is the underside of the switch board. I tried to keep as much of the circuitry on the top side as possible to help you see how everything is connected together.


47713
This image is the a labeled version of the first image showing the different parts of the circuit board.

Starting from the bottom left, we have a PCB terminal block labelled "5VDC Power Input" which provides power from Output 2 on the power supply board detailed in my previous post to the switch board itself, power for the relay on the right hand side of the switch board as well as the temperature sensor and one other device which will be shown in a later post.
The "I2C" header is for data wires from the temperature sensor and the "Serial" header is for the data wires to the other device. The I2C and serial pins on the system controller connects to "Header 2" via wires and then to the PCB terminal block. Connecting the temperature sensor and the other device to the switch board allows to everything to be connected to one circuit board instead of each device being connected to different places and makes it easier connect/disconnect devices when needed.

"Header 1" is where the controller plugs into to switch channels 1 through 7. Pin 2 of "Header 1" (counting from left to right) connects through a 10000 ohm (10kΩ) resistor which then connects to the base or switch pin of channel 1's NPN transistor. The output or emitter pin then connects to the base pin on the PNP transistor via a 1000 ohm (1kΩ) resistor. The output pin of the PNP transistor is then connected to the PCB terminal block at the top of the circuit board. When channel 1 is switch by the system controller, it causes the first transistor to switch on which causes the second transistor to switch on, this will then switch on the cage lighting. The happens moreless at the speed of light (188,000 miles per second) so there is no delay between the system controller turn switching the channel on and the LED's turning on.
Channels 1 through 6 are wired in the NPN-PNP way. Channel 1 and channel 3 also have a extra PNP transistor to allow for a later addon to the system.
Channel 7 is moreless the same as all channels where on the MkI switch board, the big white block is a 250VAC 3 Amp relay for a later addon. Channel 7 only have a single NPN transistor but it has a 1N4004 diode with a reverse voltage of 400V. This protects the rest of the circuitry incase the relay fails in such a way that causes 230VAC mains voltage to go through the coil of the relay that could lead to a major failure of the whole system and a possibly a fire.

Below is what is connected to each channel:
Channel 1: White cage lighting
Channel 2: Red cage lighting
Channel 3: Other colour cage lighting
Channel 4: System cooling fan
Channel 5: Reserved for a later addon
Channel 6: Spare channel
Channel 7: Mains voltage relay for a later addon

As I mentioned above, I decided to replace the old relay board with this transistor board to eliminate the audible click from switching the cage lighting on/off but it also allows me to fade the cage lighting up and down with a method called PWM instead of the lighting either being on or off. This helps to prevent Archimedes being blinded when I turn the white lights on at night time. PWM stands for Pulse Width Modulation, its a way of getting an analog signal from a digital controller. PWM pulses the output between 0% and 100% (in this case, 0 volt and 3.3 volt) so quickly that the eye it tricked into thinking the output, for example an LED, is being dimmed or faded. See this link for a more info on PWM. (http://www.hamstercentral.com/community/redirect-to/?redirect=https%3A%2F%2Fwww.arduino.cc%2Fen%2Ftuto rial%2FPWM)
The speed of the system cooling fan is also controlled via PWM and the maximum speed of the fan will depend on the room temperature, the warmer the room is, the faster the fan will spin. When the room temperature is below 20°C, the system cooling fan is turned off completely.

As a side note, since completing this swich board I have also reduced the voltage of Output 3 on the power supply board from 10 volt down to 6 voltage which is the same voltage as 4 AA batteries wired in series. Doing this has reduced power consumtion of the cage lighting and made the electrical wiring inside the cage (contained within plastic trunking) a little safer. Archimedes has never crewed the trunking but this reduction helps make it safer incase he does. Lowing the voltage of Output 3 to 6 volt also reduces the amount of light that the cage lighting LEDs emit but still allows the cage to be lit nicely and is enough for the system cooling fan to start and move enough air to keep the power supply cool.


Again sorry for lack of posts recently and sorry for another big update.
Take Care
Morgan + Archimedes

[mlwinters]

Hey everyone, I just wanted to let you know that I created a YouTube channel a little while ago. So far I have only upload two videos, one showing Archimedes's cage and the other showing the cage lighting. I am currently editing two more videos which will be uploaded soon.

(https://www.youtube.com/watch?v=WLDUK8MQZL8)WLDUK8MQZL8

(https://www.youtube.com/watch?v=WLDUK8MQZL8)AZmWO4-zMYw

Hope you enjoy the videos, be sure to subscribe to my channel.

Take Care
Morgan + Archimedes