back-up thermostat/dead man's switch

this is most likely symptomatic of the fact that I'm about halfway through adding on/off thermostats as failsafes to all my proportional thermostats regulating my racks and cages, but lately I've noticed a fair amount of traffic on this site and others regarding controller malfunction or failure, flexwatt wired improperly, potential fire hazards, etc.

I am fairly certain I'm going about this properly, but, acknowledging the fact that I tend to get wrapped around the axel more often than not, I would appreciate the input of anyone who utilizes a backup/failsafe dual thermostat setup. thus far I have set the backup two-three degrees higher than my primary, plugged the flexwatt/heat panel into the primary, and the primary into the secondary (and the secondary into the wall, should go without mentioning), and secured both probes in the same place. I guess my question is: independent of the heating element, do you place your backup probe in the exact spot as your primary probe? that is how I have been going about it, but again, my head is a cluttered place, and I don't always think through everything that I convince myself I have. I would also like to hear any experience with a backup malfunctioning as they tend to be of lesser quality. would a malfunction in the backup affect the primary thermostat in any way?

I know there have been a myriad of threads on this exact subject, and I've read most of them, but I cannot for the life of me find the one where someone was good enough to post an actual sketch of the proper setup. I want to say it was one of our moderators, but I might be thinking of another thread.

The only problem i could see happening is if the secondary t stat failed in a way that cut power to the primary then u would have no heat.

Your adding a variable, which Imo lessens your chance for failure.
Heat--->primary--->secondary---> power

Id much rather have my secondary fail and cut power, then my primary fail and burn the snakes if your not running a secondary.

For me, it will be my next purchase no questions asked. Probably going to a with a herpstat, because frankly I have had good luck with them.

I have a failsafe on all my T-stats. In most cases I place the probe near the primary. Accept in my rack where I place it in the top (and typically) the hottest (mine is). My snake room is unregulated, many of my probes are interior mounted (more accuracy) and the failsafe is exterior basically under the primary. I found I need about 10º to make sure the failsafe does not shut down the primary prematurely. Your description they could easily be close to the same. The only concern I would have is the accuracy of the failsafe. I find that the inexpensive on/off type to be painfully in accurate temp wise. (I have hydrofarms and they range from +1º to +3.7º over accurate) Most proportional ones are bang on accurate (all my herpstats are easily in 0.5ºF of accurate I have 20 probes of herpstats)

The only time I would question the necessity of the failsafe is with a proportional unit that runs a mechanical relay (typically will fail off rather than on) and not only a high temp shut down but a low temp one as well (if the probe gets pulled loose) The only units that run both currently are the herpstat 1-4 I believe. They are hands down the safest units around due to this innovation. The hat tips to Dion the designer for his efforts to increase the safety for reptiles and people!

http://images9.fotki.com/v114/photos...drawing-vi.jpgHosted on Fotki

thank you, that's the picture I was thinking of. and I agree, spyder robotics are well worth the price. excellent customer service as well.

We're in the process of changing things around and ordering more t-stats but the ultimate goal will be a Herpstat 1 as the primary with an on/off VE-100 as the back up for each rack and incubator. We place the probes of the primary and backup in different slots.

Love the Herpstats too:gj: . Spyder did an awesome job with these new ones. They control all of our bearded dragon lights as well.

I back up my herpstat 4 but I often question if it is needed with the features build in. the same could be said about the 1. I would never try to talk one out of a failsafe as I feel it is important to take every measure to protect the animals in my care. But with the safety features of the herpstat 1 (+) it does call it into question. I find the VE series disappointing personally, with all the features available on the competitors (helix, ecozone, herpstat, and herpkeeper) they choose to re build the simplest and oldest model (helix), it feels like a step backwards we went from great features to no features.