1. Of all the heat tracing cables I'm familiar with, none heat via|
this "carbon fiber" method. All are resistance heaters of three
basic types: self-limiting, constant watt and mineral insulated.
All work very differently but all are resistance heaters employing
wires as either the primary heating element or bus wires to carry
voltage across a matrix.
2. These people show no real specs that an engineer could use to
specify the quantities of materials needed for an application. The
vague description about using any voltage type & etc. are scary at
best. Most cables are not designed to be buried underground unless
in conduit due to the possibility of electric shock should there be
a grounding problem if the cable is damaged. Most so-called soil
heating cables are very dangerous unless you use a quality GFCI in
case of damage while energized. They also typically don't last all
3. Duran cables carry no FM or CSA approvals. The only approval
they show is a UL listing for one of the insulation materials.
Scary at best. I see insurance problems...
4. They offer no clue as to how to fabricate a circuit.
5. Real heat tracing cables have a decent output: 3 watts on up to
over 20 watts per foot with 120VAC depending upon the cable selected
for the application. Low wattage like Duran means more cable
needed to achieve a desired heating effect.
6. Real heat tracing cables are expensive due to the extensive
testing, certification and liability by the manufacturer.
Industrial cables generally start at $3.00 per foot and don't
include the price of required accessories such as thermostats, power
connection and end termination kits & etc.
I'd be very leery of their method without much more detailed
information and or test data. If you want to see more detailed info
about how the heavy duty commercial/industrial/residential cables
work, please visit this website: http://www.delta-therm.com
Kingsport, TN (Zone 6a)
----- Original Message -----
To: "Multiple recipients of list AROID-L"
Sent: Monday, November 19, 2001 4:33 PM
Subject: RE: Heating tables and anything else
: Hi Brian
: As far as the heating cables for the ground are concerned, they do
: "up north" so the "rich folks" don't have to go outside and shovel
: their sidewalks in winter. Seriously though, I read where they
are not all
: that expensive.
: I looked at your duran1 website~ me being the cynic I am, I'd
: about a company where "Jerry and Larry" are listed as US
: Interesting idea though, for the plants!
: -----Original Message-----
: From: brian williams [mailto:email@example.com]
: Hello! Well, on my quest to have the perfect growing environment
: plants I have been looking into heating cables which can heat
: the ground outside to make partially hardy plants make it threw
: Here is the website I think a few may find this product
interesting and it
: could be used for a number of things. Not to mention its
only$00.02 a foot
: and is very low watts.