For people who use thermostats: Where do you put the probe?

[reno-cg]

Right now I have my probe set up taped to the bottom of one of the tubs in my rack, underneath the newspaper. I think the problem with this set up is that it allows for my heat to fluctuate too much.

What happens is that by the time the stat reads my set temp (95), it turns off, but the heat source is still hot so the temp continues to rise up to about 97.3. It then starts to decline (because the stat has turned off the heat source) but it falls to about 94. The reason it falls is because it takes a little while for the heat source to become warm thus for the probe to read a warmer temp. I use roof de-icing cable for my heat source.

I use Herpstat, but I don't think it has the option of allowing for a steady constant heat flow; it turns off when it hits the target temp, and turns on when it is lower than the target temp. I don't want to use a dimmer switch because they don't control the temps if the temp of the room changes, so basically I just want to change my setup and hopefully it will not allow for so much fluctuation in temperature.

Anybody have any good ideas? Thanks in advance!

[Stewart_Reptiles]

I place the probe directly on the heat source.

[Vypyrz]

There are a couple of ways to attach the probe to the heater. This is how I currently have mine set-up...

Attach the probe to the bottom of the enclosure...


Attach the heat pad...


Another option is to mount the heat pad and probe to the surface that your tub sits on and just set the tub on top of it. This makes it easier for cleaning since you can just lift the tub off and clean it without having to mess with the wires.

The reason your Herpstat is acting like that is because you may have it set to "Non-Proportional". This is a function that is normally used for things like heat lamps, ceramic heat emitters, or space heaters. This basically means that the Herpstat turns on and heats up to a certain temperature then it turns off until a certain cooler temp is reached and then it comes back on. If you go into the menu and set it to "Proportional", then it will continually adjust the power to the heat pad to maintain a constant temperature. If you don't have the instruction book for it you can see it online here. I don't know which Herpstat model you have, so here are the links to all 4 of them. Hope this helps...

Herpstat Basic:
http://www.spyderrobotics.com/produc...ual_online.pdf

Herpstat ND:
http://www.spyderrobotics.com/produc...tnd_manual.pdf

Herpstat II:
http://www.spyderrobotics.com/produc...at2_manual.pdf

Herpstat Pro:
http://www.spyderrobotics.com/produc...pro_manual.pdf

[BAD Morphs]

I place the probe directly on the heat source.

X2 I also place all my probes directly on the heat tape!

[reno-cg]

Ok, I just attached the probe to the cable and it seems to have resolved my fluctuating temps for now. I have one other question as I am quite unfamiliar with Herpstat thermostats: Can you use the herpstat as a dimmer?

[steveboos]

The Herpstat is proportional, which is way better than a cheap dimmer switch which just restricts the amount of power. I would just set your Herpstat to proportional and be set.

I personally use Ranco Thermostats for my BP's and Chondro. They are on-off thermostats, but i always stick the probe directly on top of the heat source and never have temps fluctuate more than a couple degrees in my rack.

[reno-cg]

Ok I think I have it set up as good as I'm going to get it. Essentially now there is only a fluctuation of about .6 degrees f. I have the hot spots at 96.6 - 97.2. The rest of the tank is about 82. Now all I need to do is make one small correction with my rack that I built. The top space has too large of a crack and it is causing some humidity issues. Thanks for all your help!

[snakesRkewl]

IMO I'd drop my hot spot temps down to 93ish, your on the edge of tooo hot and you don't want to go over that edge.

[reno-cg]

Already done. Thanks for the advice