Impressive little 12v 100 watt heating element.
I picked up four of these to use as an air preheater project
on an auto engine similar to way Dodge uses a preheater
on their diesels. I've checked each out and while they may
register about 3.7 ohms when cold the resistance quickly
decreases when power is applied. In addition, while the units
I bought are rated 100 Watts at 12 volts they will definitely
generate more wattage out with increased voltage.
I saw as high as 128 watts when operating at 14.4 volts.
These PTC heaters are really designed for forced air
cooling to get the best results. I combined the four
units into an intake plenum and used a 44 cfm muffin
fan for an airflow test. At full fan speed the outlet was
producing about 120F. By reducing the airflow to half or
less the outlet temps would rise to 170+F. I'll probably add a
thermal snap switch to cut power to the relay operating the
heaters at 140F so they aren't trying to melt any surrounding plastics.
Overall
I'm very pleased with the PTC heaters. If you are looking for a means
to warm a small area with hot air then these are a good option."
(Important for safety)
*Verify Voltage when ordering
Chinese
surplus energy to a
dummy external load like a 12v heater
or resistor.
Proper Use See Below
Upper Thermostat
Lower Thermostat
"
For heating smaller items. 50 watts
Advnaced Uses for Peltier Modules
Cooling & heating Applications
Advantages
The main advantage of the Peltier effect is that, it allows us to build cooling/heating devices
that don’t have any moving parts, and therefore, are much less likely to fail as compared to
conventional coolers and heaters. They also require almost no maintenance.
Drawbacks
The major disadvantage of the Peltier effect is that, it is inefficient.
The flowing current itself tends to generate a significant amount of heat,
which gets added to the overall heat dissipation. In large applications,
this results in an excessive amount of heat, which needs to be taken care of.
Typically, additional fans have to employed to fix this problem.
