Installing heating in a rack system

[MouseKilla]

Just wondering if someone could post a couple of pics of how they have installed the heat tape in their racking systems. If anyone has any other methods to properly heat a rack I wouldn't mind seeing those either. I'm pretty sure I can put a rack together for myself but I've never used flexwatt before so I wouldn't mind seeing how it's spread out over multiple shelves and wired up and stuff like that.

[mykee]

Check out my gallery for a few pics as to how I did just that.

[Stockwell]

If you're using flat wooden shelves the best way is to router a slot for it, or do it with dado blades, if you have them, but this of course is extra work and requires the right tools.
If you're not equiped to do that, run a length across the back of each shelf and allow a couple inches to over hang at one side, for your hook up.

I fasten mine down with a staple gun and quarter inch staples, but make sure you only pierce the clear outer mylar, and you don't contact the internal black bus conductors, as you don't want your staples to be "LIVE"
You should insulate each end with electrical tape so that the exposed part is covered , as it will be live
The transisiton in levels between the shelf and the tape would normally cause a bump when you push the tray in, and this is why routering a groove is beneficial, as installing below grade prevents this, but if you dont have the equipment to make a slot for the tape, then put a piece of 2 inch wide duct tape over the edge so that the tray wont snag the heat tape everytime you push the trays in. The tape simply makes the transition more smooth.
If your rack will have several levels you should consider a separate dimmer for every 2 or 3 shelves, because different settings will be required to compensate for it being colder near the floor and hotter the higher up you go.

The tape is connected at one end, and the differecnt levels are simply parallel connected with lamp cord. The dimmer must then be put in series with one side of line which feeds each parallel group of shelves
You can use the special crimp connectors and insulators that flexwatt provides
I 'm afraid I don't have any wiring pics on this site..perhaps somebody else will

[MouseKilla]

Thanks guys. I had a look at your pics Mykee but my monitor kinda sucks and I couldn't really make out exactly how it was set up. Is it run horizontally across the first shelf then down one side of the rack then back the other way across the next shelf or does each shelf have seperate wiring?

[mykee]

Killa, that's exactly what I did, it uses more tape that way, but I don't have to wire off each level. I used 16 odd feet of continuous tape for that rack in particular and if holds 10 34x16x6 rubbermaids.

[Stockwell]

Killa, theres a variety of ways to wire heat tape. There is no right or wrong way. It all depends on what the builder finds least complicated, and how fancy you want it.
I've seen tape, weaved back and forth through slots in the sides of racks, and this simplifies wiring, but wastes lots of expensive heat tape, however it sure saves time and complexity of attaching wires to each level, as mike suggests.

Ball python breeders sometimes, run 10 inch heat tape down the back of a rack, vertically, and that is pretty easy as well. This simply heats the back of the trays rather than the bottoms. The heat spreads out anyway, so that technique is fairly popular. When snakes need more heat the simply squeeze up against the back wall of the rubbermaid.
The only disadvantage to wiring the entire rack with on piece of flexwatt is that the higher racks will always be hotter. Hot air rises, so all the lower rack heat drifts upwards and tends to make the top shelves several degrees hotter than the bottom ones.
Some guys will just adust how close the tray is to the tape to compensate for this.
Below is a pic of how I wire racks.
The sides have slots in them, cut with a jig saw to accept the heat tape, and each level is wired separately.
Every 3 shelves has its own dimmer, and indicator light. The dimmers and indicators are wired to the right in the separate wooden compartment. This provides an attractive "control panel" on the side of the rack, and hides all the terminations and electrical boxes. There are also indoor outdoor thermometers installed on this side panel to display the temp of every third rack, and these thermometers are used to adjust the dimmers, so that all shelves are at the same temperature.
I hope this is of some help
http://www.ssnakess.com/photopost/data/500/1801flexwattwiring-med.jpg

[mykee]

Wow Roy, I've always been worried about wiring each level for fear of a few things, one being the sloppiness of the work, but your set-up is very neat and clean. I especially like how you added extra width to your rack to cover all the 'ugliness'. Very original.

[crazyboy]

To make a channel in the shelve for heat tape what isthe simplest way to do this. I think it would take a long time to dao that wide of a channel with a router.

[MouseKilla]

Wow Roy, that is one hell of a rack! I take it that each set of 3 shelves is powered seperately? In other words I'm wondering if there are 4 wall plugs for the rack pictured in the foreground? I wasn't sure if at the end I would have one plug for the whole works or a seperate one for each shelf.

[Stockwell]

One plug, for the whole works, no problem... 3 inch heat tape is only 5 watts per foot
Every 3 shelves is on a separate dimmer but all dimmers are fed from one main cord..

[MouseKilla]

Better than I'd hoped! Thanks! Now if I can only assemble the whole thing without injuring myself too badly I'm set. lol

[Lisa]

We wire each level by scraping a little bit of plastic off with a soldering iron then running a screw with an eyelet connector through. to insulate we put on a dab of glue. you can see in our rack building post linked below.

http://www.ssnakess.com/forums/showthread.php?s=&threadid=13672

I do like roy's idea of a dimmer and thermometer for every third or so shelf, though that can raise costs significantly. depends on what you've got in the rack i guess.

[Stockwell]

Hi Lisa... I've been trying to keep it a secret(hush!!! LOL) but I also hook up heat tape with number 8 or 10 truss head screws, inside star lock washers and crimp ring terminals... You'll notice you don't see any of those expensive clamp on jobs in these photos.

I don't generally advertise it because it's safer for amateur electricians to use the proper amp insulators and crimp connectors which make multiple penetrations and provoide a more sound connection.

[Tim_Cranwill]

Pssss... I use ring terminals and screws too. ;) Fast, easy and reliable if done properly....

But like Roy said, I wouldn't recommend anything but the manufacturer's assembly methods for many reasons.