Building an incubator and I need all kinds of advice.

[cluelesshillbilly]

I want to first thank you sincerly for y'alls help. The project is really broken down into a few small issues. Mechanically I can build anything but when it comes to high accuracy thermostats, intermitent switches, and making it all work I need Y'ALL! For the turner I am using a BBQ rotisery motor but because the motor turns 3 rmp I need it to come on for 15 seconds every 60 minutes. It motor is 120v and very low amperage. Secondly I could buy a thermostat switch( **broken link removed** ) but would rather use a electronic highly accurate thermostat in the vent return duct. I need 100 degrees F with no more than 0.5 degrees of error. I can make this system 120v or 12v depending on what I can do about heating the cabinet. I have several 12v fans at my disposal and had considered using a 12v window defroster style heater but then I saw this Incukit ( **broken link removed** ) on eBay and said I can build that if I knew where he got the ceramic elements.

 

[JimB]

Having had a look at the IncuKit, it looks as though the "ceramic elements" are just wire wound resistors with a ceramic case.
From an electronics point of view there is nothing magical about these.
If you went to a place where they sell electronic components and asked for 10watt wirewound resistors you would get something suitable.
The only problem is, what value of resistor ie what resistance. Not knowing what heating power you require, it is impossible to suggest what values to use.

JimB

 

[Boncuk]

Hi,

I do not recommend to use an assembly like this.

The fan obviously blows against the heater element at a distance smaller than the fan diameter which causes an extremely turbulent air stream - not to talk about aerodynamic (fan pressure) losses because of missing guides. (An airstream bumping against an obstruction at a 90degrees angle loses 50% of pressure - good enough for a shoebox.)

As I know from other incubator box designers the warm air has to be distributed evenly throughout the box, which is very hard to achieve with a high resistance on either upstream or downstream.

Circulating the internal air mixed with a certain amount of fresh air requires low restistance (or high pressure) for the fan to get the air to any spot within the box.

Mechanical thermostats are accurate within ±2 degrees which makes them unusable for an incubator.

I have designed an incubator control circuit featuring a 14-bit combined temperature/humidity sensor, a power output circuit for a heater up to 400W (ensuring temperature stability of ±0.2deg/C), air humidifier also rated 400W (heavy overkill) and an egg turner programmable to turn eggs at hourly intervals starting at zero (turner disabled) up to 24 hours.

The circuit also includes diagnostics and malfunction indication and manual testing of peripherals.

If you are interested drop a PM.

Boncuk

 

[cluelesshillbilly]

Having had a look at the IncuKit, it looks as though the "ceramic elements" are just wire wound resistors with a ceramic case.
From an electronics point of view there is nothing magical about these.
If you went to a place where they sell electronic components and asked for 10watt wirewound resistors you would get something suitable.
The only problem is, what value of resistor ie what resistance. Not knowing what heating power you require, it is impossible to suggest what values to use.

JimB

A 3 cubic foot space needs to maintain 100F.