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View Full Version : one more temperatur controlling??


crazyboy
03-29-04, 04:24 PM
when using a thermostat can i set it up to keep different racks at different temps using a rheostat and set the thermostat up high so that it will cut off if the temp exceeds it? or woudl i be better off getting one thermostat for every rack that has to stay at the same temp? or one for every rack?


ex. lets say i have 2 racks with colubrids, one rack with balls, one rack with leos and 1 rack with rosy/sandboas.

bidden
03-29-04, 05:50 PM
there is a system out there somewhere(look in the classified section here,it's one of the supporters on the top part of the section) but It's like $200 or something riduculus like that

Stockwell
03-29-04, 06:53 PM
Crazyboy, you're thinking along the right lines..:)
Both approaches are possible
It is a good idea to keep separate racks for separate species, but only if they require different temps.
It's usually NOT necessary to have one dimmer for every single level, but it's a good idea to use one dimmer(they technically are not rheostats) for every couple of shelves in a rack, because heat rises, so when just using one to control a tall rack, you will likely have the standard problem with it being too hot at the top and too cold at the bottom.
I get around that problem the cheap way by moving the heat tape further from the trays, in the higher levels. This is only possible in some designs with open or vented backs and extra room at the back of the rack where you can adjust the positioning of the heat tape.
Simply moving the heat tape further away, at higher levels has the same effect as having less watts, at the top of the rack and more at the bottom. Its the cheap way of getting around having multiple dimmers. Notice I said "cheap" and not "best".
It's all a function of what you want to pay , and how much work you want to do on automating your rack.
I actually have Rosy boa racks(9 levels, 18 trays) on one dimmer, then in series with that dimmer I have a wafer thermostat, mounted under the top tray... The wafer T is my high limit cut off, in case the room simply gets too hot in summer, it switches off all the heat tape to the entire rack, until the room cools down again.
This isn't ideal, but it works, and it was the cheapest way to do it at the time.
If you have the money, those nice little Helix controllers are dandy. I tend to make my own electronics as you know, and one of these days I will make some extra incubator contoller boards to control my racks but I just can't find the time.
Many guys use the Helix for constant termperature control,and of course that removes the problem with changes in room ambient, and that is one thing a dimmer wont do. Dimmers have no feed back and aren't controllers.

You know what they say! Necessity is the mother of invention.
Experiment and see what works best for you within your budget.

crazyboy
03-29-04, 06:59 PM
ok thanks...stockwell that was a very informative post