Epoxy Edge Sealing - Superior Moisture Protection
In many applications it is necessary to protect thermoelectric cooling modules from moisture infiltration. A moisture barrier is used to prevent a degradation in performance, or catastrophic failure, of the module due to junction corrosion or electrical short.
The most typical protection supplied by most manufacturers is a bead of silicon-based sealant, such as RTV, around the perimeter of the module. While RTV will keep droplets out, water vapor can penetrate the material and become trapped inside a thermoelectric cooler.
We use an "aircraft grade" epoxy alternative to RTV
- with much lower vapor permeability.
The dielectric, mechanical and physical properties of the two sealant types follow:
|Technology||One-component TRV rubber||Two-component RTC rubber|
|Viscosity||Thixotropic Non-slumping||Thixotropic Non-slumping|
|Hardness, Shore A||40||80|
to Al2 O3 ceramics kg/cm²
|Coefficient of thermal conductivity, W/mºK||0.21||0.1280|
|Volume resistance, Ohm·cm||3·1014th||1·1015th|
|Dielectric strength, KV/mm||25||17|
|Dielectric Constant at 1 MHz||2.9||3.1|
|Dissipation factor at 1 MHz||3·10-3rd||1·10-2nd|
|Operating temperature, ºC||-40 ~ +180||-50 ~ +200|
TE Modules manufactured with an Epoxy perimeter seal are designated with an "E" suffix
(for example: TM-127-1.4-6.0 "E").