Ranco Digital Two-Stage Temperature Controller question

[geno_47]

Can I use a splitter to attach 2 ferm wraps to the controller? I would like to have two ferm wraps and the chest freezer controlled by 1 unit.

Thanks in advance!

 

[RoadKing]

By looking at 'em, I don't think they'll draw too much, even if they're both on. Do you have room for a porcelain heater in there?

 

[geno_47]

Why yes I do...didn't even contemplate that as an idea....thanks! Im assuming you've used this and it works well? Any tips/tricks regarding that kind of heater?

 

[passedpawn]

Why yes I do...didn't even contemplate that as an idea....thanks! Im assuming you've used this and it works well? Any tips/tricks regarding that kind of heater?

I've got one in my fermentation freezer. Get a very low wattage one to be safe. I have a 200W heater that I got off Amazon for about $15. It has a fan and works perfectly for keeping my 15cu.ft. at temp. I run mine off my 2-stage controller as well.

 

[marcb]

I've got one in my fermentation freezer. Get a very low wattage one to be safe. I have a 200W heater that I got off Amazon for about $15. It has a fan and works perfectly for keeping my 15cu.ft. at temp. I run mine off my 2-stage controller as well.

Look up the specs on the controller. I believe the internal relays are good to 15amps on each side. I use these on my fermenter and have a gfi outlet strip connected to two 12a 12v power supplies that drive my peltiers for cooling. I have also hooked up drum heaters through these at 750-800w without issue. These babies are workhorses.

 

[RoadKing]

Yeah, I use one And my ferment chamber is outside in the shed all year long. Just make sure it's not too overpowered. I put a piece of sheet metal between the heater and the fermenters so it doesn't blow directly on them.
Here's a small one... http://www.target.com/p/lasko-my-heat-personal-ceramic-heater-black/-/A-13671584?ref=tgt_adv_XSG10001&AFID=Google_PLA_df&LNM=%7C13671584&CPNG=Home+Improvement&kpid=13671584&LID=PA&ci_src=17588969&ci_sku=13671584
Sorry couldn't shrink link...

 

[day_trippr]

Look up the specs on the controller. I believe the internal relays are good to 15amps on each side.[...]

The Ranco ETC-211000-000 (<= pdf of manual there) dual stage controller relay ratings are actually quite a bit lower than 15 amps.

120VAC NO = 9.8A NC = 5.8A
240VAC NO = 4.9A NC = 2.9A

Cheers!

 

[marcb]

The Ranco ETC-211000-000 (<= pdf of manual there) dual stage controller relay ratings are actually quite a bit lower than 15 amps.

120VAC NO = 9.8A NC = 5.8A
240VAC NO = 4.9A NC = 2.9A

Cheers!

Crazy, I thought they were higher! I also have never blown one and I definitely push them to their limit.

 

[day_trippr]

fwiw, I only posted that because recently someone overloaded a Ranco and ended up with a pretty well charred controller.

I've been using a pair of Ranco single stage units for a keezer and a fermentation cabinet heater, but both loads are well below the relay limits. The only ding I have on the Ranco units is the lack of an anti-short-cycle function, but with strategic probe placement you can still run as low as 1 degree differential without cooking a compressor...

Cheers!

 

[geno_47]

Thanks for all the responses. It's got me on the right track now. As far as probe placement, where should I put it? I've seen threads where some put it directly into the fermenter, some put it in a glass of water and leave it in the chest freezer and others where they put the probe inside the chest freezer not in either. I would think directly in the fermenter would be the most accurate.

Thanks!

 

[day_trippr]

I place the probe against the side of the carboy or keg about midway up, cover it with a ~5" square piece of 1" thick closed cell foam, then strap that tight with a velcro band. The only thing that would track tighter is a probe in a thermowell immersed within the vessel, but frankly the half-degree inaccuracy the external probe provides vs a thermowell'ed probe is plenty tight enough for me.

The thermal mass of the vessel and contents along with the isolation from external influence provides the hysteresis necessary to avoid frequent compressor cycling. I use this method in my keezer, fermentation fridge, carbonation fridge and fermentation cabinet.

Using a small vessel of water is similar, it just provides much less hysteresis, and if you're not careful a dead probe...

Cheers!

 

[RoadKing]

Don't put it in water, the probe is not waterproof. Tape it to the side of the fermenter about half way down, then tape a piece of insulation over that so it doesn't read ambient temps.
Insulation can be anything, like a folded up paper towel, an old sock, etc...

 

[geno_47]

Thanks for all the advice