Herpstat 1 temp fluctuations

[TimNA]

I am having a issue with my Herpstat 1. It will not hold a steady temp for longer than a week.

I set the temp to 93 and gives my tubs 90. A few days later it's still set at 93 but the inside of the tub is 86. So I bump it up till the inside reads again 90 +/-, usually the herpstat reads around 96. Everything is fine, then a week goes by and the temp in the tub drops again to 86 +/-.. Anyways you get the point. It's been doing this for the last few months. I am thinking the probe maybe is going out? I finally gave up & am just using my VE-200 again since at least it's consistent.

The probe was attached to the top of the flexwatt using tape.

[snake lab]

Im convinced probes get ruined by prolonged contact of the prob directlly to heat sources. Years ago i used to attach the pribe right to the flexwatt and i went through 2 probes on my helix. I quit doing this and use a dummy tub in every rack bow instead of attaching the probe directlly to the heat and never had an issue since and its been about 10 years. I may be wrong but its the only thing i can think it was

[kitedemon]

Is the room temp constant? The ambient room temp variations will shift the tub temp with the probe on the heat tape. You should write Dion and ask for input.

[kitedemon]

I have been testing the a new Herpstat 4 and as near as I can tell the probes are absolutely perfect. I get a 0.1ºC low according to my calibrated thermometer on all the probes. I can't say about the HS1, but the probe accuracy on the HS4 is astounding.

[The Serpent Merchant]

I have been testing the a new Herpstat 4 and as near as I can tell the probes are absolutely perfect. I get a 0.1ºC low according to my calibrated thermometer on all the probes. I can't say about the HS1, but the probe accuracy on the HS4 is astounding.

I absolutely love my herpstat 4's, a truly phenomenal product all around.

[TimNA]

Yeah the room is heated to 80 & doesn't fluctuate much from that. I am thinking it has to be the probe. I will put a email into them & see what they say.

On a side note I see they just came out with a new version. How does it compare to the older one? I like the ve 200 but like the ability of the herpstat allowing finer tuning of the temp instead of full degrees that the ve does.

I have my ve at 93 tubs are 91, if I set it to 92 tubs are 88-89.

[The Serpent Merchant]

Yeah the room is heated to 80 & doesn't fluctuate much from that. I am thinking it has to be the probe. I will put a email into them & see what they say.

On a side note I see they just came out with a new version. How does it compare to the older one? I like the ve 200 but like the ability of the herpstat allowing finer tuning of the temp instead of full degrees that the ve does.

I have my ve at 93 tubs are 91, if I set it to 92 tubs are 88-89.

the new models have a lot more functionality than the old ones, as well as better circuitry that makes them safer.

Here is the new Herpstat 1's user manual: http://spyderrobotics.com/products/h...t12_manual.pdf

[spyderrobotics]

Hey Tim! I got your response email. Sounds like your Herpstat is in need of service and we will take care of that for you under warranty. I emailed the info to you.

I noticed in original post you called the unit a Herpstat 1 however its actually the original Herpstat. I know our new name strategy will be a little confusing initially for people to tell what is old and new product but basically anything with a number after it is new product line (1 Basic, 1, 2, 4) other than the new Intro.

Putting the probes on the heat tape should have no issue with longevity. The sensor is actually rated up to over 200 degrees (and I've had them in the oven before testing them). My code cuts the readout internally around 155 degrees if I remember right.

And to reiterate some of my email to Tim turning up the temp on a Herpstat does not increase power output. The previous generation product did have semi-adjustable curce and you could bump the target temp a few tenths to cheat the curve but this would only apply if the sensed temp was within a degree of the target temp. Below that and the unit would be full ON. So the fluxuations must be a power issue somewhere in the circuit. Could be the fuse or the triac but unusual. Only thing that comes to mind initially was a herpstat that someone bought used and it had same symptom. Had them send it in and when I opened it up the previous owner had popped the fuse and wrapped aluminum foil around the fuse to get it to work. The aluminum would only hold so much current and it was slowly burning away. For the record....don't wrap safety fuses with aluminum foil and if you do tell the next owner.

Anyway, send that unit in Tim and we'll take care of you.

Dion Brewington
Owner, Spyder Robotics

[The Serpent Merchant]

Yet another reason why I will only use herpstats on my enclosures!

[TimNA]

Hey Tim! I got your response email. Sounds like your Herpstat is in need of service and we will take care of that for you under warranty. I emailed the info to you.

I noticed in original post you called the unit a Herpstat 1 however its actually the original Herpstat. I know our new name strategy will be a little confusing initially for people to tell what is old and new product but basically anything with a number after it is new product line (1 Basic, 1, 2, 4) other than the new Intro.

Putting the probes on the heat tape should have no issue with longevity. The sensor is actually rated up to over 200 degrees (and I've had them in the oven before testing them). My code cuts the readout internally around 155 degrees if I remember right.

And to reiterate some of my email to Tim turning up the temp on a Herpstat does not increase power output. The previous generation product did have semi-adjustable curce and you could bump the target temp a few tenths to cheat the curve but this would only apply if the sensed temp was within a degree of the target temp. Below that and the unit would be full ON. So the fluxuations must be a power issue somewhere in the circuit. Could be the fuse or the triac but unusual. Only thing that comes to mind initially was a herpstat that someone bought used and it had same symptom. Had them send it in and when I opened it up the previous owner had popped the fuse and wrapped aluminum foil around the fuse to get it to work. The aluminum would only hold so much current and it was slowly burning away. For the record....don't wrap safety fuses with aluminum foil and if you do tell the next owner.

Anyway, send that unit in Tim and we'll take care of you.

Dion Brewington
Owner, Spyder Robotics

Thanks again Dion! I just read your email & was coming here to update the post with your response . I will get the rma filled out and send it in asap.